Navegando por Assunto "Rato como animal de laboratório"

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Acesso aberto (Open Access)
Ajustes motores compensatórios após lesão isquêmica focal unilateral do trato corticoespinhal
(Universidade Federal do Pará, 2017-06-30) CARVALHO, Walther Augusto de; BAHIA, Carlomagno Pacheco; http://lattes.cnpq.br/0910507988777644; PEREIRA JÚNIOR, Antônio; http://lattes.cnpq.br/1402289786010170
The aim of this work was to develop a new model of spinal cord injury caused by focal and unilateral transient ischemia after ET-1 microinjection in the dorsal funiculus and to evaluate the sensorimotor alterations of the anterior paw of rats (Wistar). Fifty (n = 50) animals (CEPAE / UFPA protocol BIO007912), who were trained, thirty-three (n = 33) were selected to compose control (n = 15), sham (n = 6) and injury (n = 12) groups. By using a micropipette, we injected the volume of 250 nL of saline (sham) or endothelin-1 (lesion) near the medial dorsal artery of the cervical segment C4 at a depth of 1 mm from the pial surface of the spinal cord. ET-1 induced cystic cavity formation of 0.421 mm2 (± 0.035 mm2, n = 3) on the corticospinal tract and suprajacent white matter, ipsilateral to the microinjection site that can be measured in cross-sections (50 μm) stained by the Nissl technique. The motor functions of the forepaw were evaluated by specific sensorimotor tests before and after injury at 3, 7 and 14 days. The results were evaluated by the ANOVA statistical test with Tukey post-hoc analysis (α = 0.05). Our results show in pasta test that after injury there is a compensatory motor behavior in which the non-preferential forepaw assumes the functions of the preferential forepaw. The Staircase test revealed a decrease in the ability to grasp the object with the preferred paw and the Contact test showed a decrease in sensitivity of the preferred paw.
Acesso aberto (Open Access)
Avaliação da atividade antinociceptiva e anti-inflamatória da Pellucidina A e elucidação do mecanismo de ação em modelos in vivo
(Universidade Federal do Pará, 2016-10-13) QUEIROZ, Amanda Pâmela dos Santos; MAIA, Cristiane do Socorro Ferraz; http://lattes.cnpq.br/4835820645258101; BASTOS, Gilmara de Nazareth Tavares; http://lattes.cnpq.br/2487879058181806
The Peperomia pellucida (Piperaceae) is an herbaceous plant commonly found in the American and Asian continents. In the Amazon the species is known by the name of erva-de-jabuti. This plant is used in folk medicine to treat a wide range of symptoms and diseases such as conjunctivitis, headache, asthma, gastric ulcer, inflammation and arthritis. Pellucidin A is an isolated compound of the species Peperomia pellucida and this study aimed to analyze the antinociceptive and anti-inflammatory activity of this compound, as well as to elucidate its mechanism of action. For the assays, male albino mice (25-40 g) were used, which were initially treated with pellucidin A at the doses of 0.5; 1 and 5 mg / kg (i.p.) and subjected to locomotor evaluation by the open field test and animal models of acute pain, such as acetic acid-induced abdominal writhing tests, formalin tests and the hot plate test. The acetic acid-induced abdominal contortion test was realized to elucidate the mechanism of action in which the animals were treated at the standard dose of 5 mg/kg (i.p.) and for anti-inflammatory analysis of the compound was used model of granuloma induced by pellets of cotton, in which the animals were treated in the dose of 10 mg/kg (i.p.). The compound did not show capacity to change the ambulation of the animals at any of the administered doses. In the contortion test, pellucidin A was able to inhibit the number of abdominal writhings in 43% at the dose of 1 mg/kg, and 65% at the dose of 5 mg/kg. In the formalin test, an antinociceptive effect was observed at the dose of 5 mg/kg, with a 68% reduction in the lymph time of the animal's paw in the inflammatory phase, showing a similar response to Indomethacin used at a dose of 10 mg/kg as positive control for this phase. Animals treated with pellucidin A and subjected to the hot plate assay did not show any change in their latency time on the plate, showing a similar response to the animals treated just with the vehicle solution. For the elucidation of the action mechanism, the pellucidin A was administered at the standard dose of 5 mg/kg (i.p.) and associated with Indomethacin (5 mg/kg i.p.), NS-398 (10 mg/kg i.p.) cyproeptadine (0.5 mg/kg i.p.), naloxone (1 mg/kg i.p.) and L-NAME (5 mg/kg i.p.). The pellucidin A has shown a synergistic action when associated with cyproeptadine and L-NAME, with a decrease in the pattern of abdominal writhing by 97% when associated with cyproheptadine and 96% with L-NAME. In the analysis of the action of pellucidin A (10 mg/kg i.p.) in the granuloma test induced by cotton pellets, pellucidin A presented anti-inflammatory activity, reduced granuloma formation in 24% in the treated mice. The results confirm the hypothesis that pellucin A presents analgesic activity capable of interfering in the inflammatory process, acting as a possible glucocorticoid agonist.
Acesso aberto (Open Access)
Avaliação in vitro do efeito genotóxico e neurotóxico da rotenona em populações neuronais de encéfalo de ratos
(Universidade Federal do Pará, 2011-12-28) LIMA, Geovanny Braga; YAMADA, Elizabeth Sumi; http://lattes.cnpq.br/7240314827308306
Parkinson’s disease is a neurogenerative disease that affects dopaminergic neurons of the substantia nigra whose neurons Project to the striatum. Rotenone is a compound widely used as pesticide and which has been implicated among the environmental factors that increase the risk of developing PD. An essay that evaluate DNA damage, such as the eletroforesis comet essay, was introduced in the present work, to better understand the neurotoxic effects of the rotenone in a experimental model of PD. The comet assay was applied to neurons from mixed mesencephalic cultures exposed to different concentrations of rotenone in two different exposure times, 24 and 48 hours. The mean comet damage index showed a significant difference between the control condition and all the rotenone concentrations tested in both exposure times. However, in the comparative analysis considering time exposure for equivalent concentrations, there was significant difference only with 20 and 30 nM rotenone concentrations. This study demonstrated that, in the experimental conditions used, the comet assay detected damage to the genetic material without detectable alterations in the MTT viability test (5 nM rotenone, 24h), suggesting that genotoxic alterations may precede viability alterations in rotenone-exposed neurons. It is not possible, however, to assure that such alterations are irreversible or not.
Acesso aberto (Open Access)
Caracterização da injúria no córtex motor de ratos em um modelo de exposição crônica ao metilmercúrio (MeHg)
(Universidade Federal do Pará, 2016-12-21) SANTANA, Luana de Nazaré da Silva; LIMA, Rafael Rodrigues; http://lattes.cnpq.br/3512648574555468
The mercury is an environmental contaminant which poses a great risk to human health. Exposure to this toxic metal occurs mainly through a diet contaminated by methylmercury (MeHg) in low concentrations and over a long period of time. Thus, in this study we propose an assessment of the effects of MeHg on the motor cortex in an animal model of chronic exposure and low dose, similar to dietary exposure in areas of high environmental toxicity of mercury. Adult rats were exposed to MeHg for 60 days with a dose of 0.04 mg/kg/day, while the control group received only the vehicle. After this period, they were subjected to behavioral testing in order to evaluate the motor performance after mercury exposure, and then sacrificed and evaluated for oxidative biochemical parameters (change in the concentration of nitrite - NO Lipid Peroxidation - LPO and Antioxidant Capacity Total) as well as evaluation of total deposits of mercury in the motor cortex and changes in cell density of neurons and astrocytes. Data were tabulated and statistically analyzed by Student's t-test (p <0.05). It was possible to observe total mercury deposits in the motor cortex, and deficits in motor parameters, with a reduction in the overall locomotion, on balance and increase in the number of failure, coupled with a significant increase in the levels of NO and LPO and decreased ability antioxidant full of animals exposed, reducing the population of astrocytes and neurons compared to control animals these findings suggest that exposure of adult animals to MeHg, even at low dose and chronically, causes changes in the motor cortex with damage to their functions.
Acesso aberto (Open Access)
Caracterização dos efeitos comportamentais, teciduais e bioquímicos da administração intermitente e episódica de EtOH em ratas da adolescência à fase adulta
(Universidade Federal do Pará, 2016-10-18) FERNANDES, Luanna de Melo Pereira; MAIA, Cristiane do Socorro Ferraz; http://lattes.cnpq.br/4835820645258101
The consumption of ethanol (EtOH) is enhanced particularly in adolescent female pubic. The EtOH intake and intermittent episodic own consumption rate around 3 times per week. The toxic effects of this kind of consumption is especially dangerous over the continuous consumption of EtOH followed due to the high dietary intakes of abstinence, causing major changes in the central nervous system (CNS) maturing in a short time consumption. Considering the epidemiological relevance and the harmful effects of EtOH on the oxidative balance, hormone production and neurotrophin CNS maturing, the aim of this study was to investigate the behavioural, tissue and biochemical responses derived from intermittent and episodic consumption of EtOH in rats in phase from adolescence to adulthood. Wistar female adolescents (n = 80) received by gavage, distilled water or EtOH (3 g/kg/day) for 3 consecutive days per week. The animals were assessed seven and a half hours after the last administration day 1, 4 and 8 weeks of episodes of binge drinking (37, 58 and 86 DPN, respectively), besides, a period of 14 days of abstinence was added after BD 8 (100 DPN) to evaluate the ability to reverse the CNS damage generated on it. The battery of behavioural tests consisted of spontaneous locomotor activity, object recognition, elevated plus maze, test pole, walking beam and rotarod. The animals were sacrificed and blood samples collected for evaluation of corticosterone levels of malondialdehyde, catalase activity, the activity of superoxide dismutase and glutathione content. Therefore, the hippocampus was dissected to quantify the immunocontent BDNF. The administration of EtOH reached average peak blood concentration of 197.4 mg / dL and the period of 7.5 hours after the last administration EtOH in acute binge blood concentration was 0.7 mg / dL. Thus, the animals underwent behavioural tests post-consumer EtOH, not under the drug effect. Consumption of EtOH in binge did not affect weight gain of adolescent animals into adulthood, however, reduced the exploratory locomotor activity, impaired motor coordination, balance and motor learning associated with bradykinesia, as well as loss in the mnemonic process and increased anxiety-like behaviour. These losses were accompanied by hormonal elevation of corticosterone, reduced hippocampal BDNF levels and systemic imbalance in the oxidative balance. Thus, it was possible to identify that the damage found on the similar behaviour to anxiety, short-term memory, bradykinesia and spontaneous locomotor activity appeared from EtOH post-consumption for three consecutive days, however, they showed no recovery or worsening of damage after repeated episodes. In contrast, there was recovery of short-term memory in object recognition task associated with the return of normal levels of BDNF in adulthood. Moreover, it showed worsening in motor learning in young adult phase followed by gradual and partial recovery after prolonged period of drug withdrawal, yet the loss of motor coordination and balance remained in adulthood.
Acesso aberto (Open Access)
Composição química e efeitos antinociceptivo e antiinflamatório em roedores do óleo essencial de Peperomia serpens (Sw) Loud
(Universidade Federal do Pará, 2011-06-20) PINHEIRO, Bruno Gonçalves; MAIA, José Guilherme Soares; http://lattes.cnpq.br/1034534634988402; SOUSA, Pergentino José da Cunha; http://lattes.cnpq.br/9909053957915090
The Peperomia serpens (Piperaceae), popularly known as “carrapatinho”, is an epiphyte and herbaceous liana grown wild on different host trees in the Amazon rainforest. Its leaves are largely used in Brazilian folk medicine to treat inflammation, pain and asthma. This study investigated the effects of essential oil of P. serpens (EOPs) in standard rodent models of pain and inflammation. The antinociceptive activity was evaluated using chemical (acetic acid and formalin) and thermal (hot plate) models of nociception in mice whereas the anti-inflammatory activity was evaluated by carrageenan (Cg) - and dextraninduced paw edema tests in rats croton oil-induced ear edema, as well as cell migration, rolling and adhesion induced by Cg in mice. Additionally, phytochemical analysis of the EOPs has been also performed. Chemical composition of the EOPs was analyzed by gas chromatography and mass spectrometry (GC/MS). Twenty five compounds, representing 89.6% of total oil, were identified. (E)-Nerolidol (38.0%), ledol (27.1%), α-humulene (11.5%), (E)- caryophyllene (4.0%) and α-eudesmol (2.7%) were found to be the major constituents of the oil. Oral pretreatment with EOPs (62.5-500 mg/kg) significantly reduced the writhing number, with an ED50 value of 188.8 mg/kg that was used thereafter in all tests. EOPs had no significant effect on hot plate test but reduced the licking time in both phases of the formalin test, an effect that was not significantly altered by naloxone (0.4 mg/kg, s.c.). EOPs inhibited the edema formation induced by Cg and dextran in rats. In mice, EOPs inhibited the edema formation by croton oil as well as the leukocyte and neutrophil migration, the rolling and the adhesion of leukocytes. These data show for the first time that EOPs has a peripheral antinociceptive effect that seems unrelated to interaction with the opioid system and a significant anti-inflammatory effect in acute inflammation models.
Acesso aberto (Open Access)
Copaiba oil effect on experimental jaw defect in Wistar rats
(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2015-02) SILVA, Priscilla Flores; BRITO, Marcus Vinicius Henriques; PONTES, Flávia Sirotheau Corrêa; RAMOS, Suzana Rodrigues; MENDES, Laís Cordeiro; OLIVEIRA, Louize Caroline Marques
PURPOSE: To evaluate the effects of copaiba oil on jaw defects repair in Wistar rats treated with bioglass or adipose tissue. METHODS: A jaw defect was randomly created in forty-two rats and filled with bioglass or adipose tissue. The two groups (Gbio and Gcell) were subdivided in three subgroups with seven animals each according to gavage administration: control (distillated water), oil (copaiba oil) and melox (meloxicam). Euthanasia was performed after forty post-operative days. The bone formation was analyzed regarding the histological aspects. RESULTS: The osteoclasts activity was observed only in four subgroups (p=0.78). Regarding the osteoblasts presence, it was very similar between the subgroups, the difference was due to Gcell-melox (p=0.009) that presented less osteoblastic activity. The inflammatory cells were more evident in Gcell-melox subgroup, however, there was no difference in comparison with the other subgroups (p=0.52). Bone formation was observed in all subgroups, just two animals showed no bone formation even after 40 days. More than 50% of bone matrix mineralization was observed in 56% (23 animals) of the analyzed areas. The bone matrix mineralization was not different between subgroups (p=0.60). CONCLUSIONS: The subgroups that received copaiba oil showed bone repair, although not statistically significant in comparison to subgroups treated whit meloxicam or controls. Copaiba oil administered by gavage had no effect on bone repair in this experimental model.
Acesso aberto (Open Access)
Copaiba oil effect under different pathways in mice subjected to sepsis
(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2014-08) BOTELHO, Nara Macedo; SILVEIRA, Edvaldo Lima; LOPES, Letícia Nobre; SANTOS, Felipe Augusto Folha; TEIXEIRA, Renan Kleber Costa; SILVA, Thaís Travassos da
PURPOSE: To evaluate the effects of copaiba oil administered by different routes on survival of mices subjected to cecal ligation and puncture. METHODS: Thirty two mice were distributed into four study groups (N=8): Sham group: normal standard animals; Control group: submitted a cecal ligation and puncture (CLP); Gavage group: submitted a CLP, and treat with copaiba oil by gavage; and Subcutaneous group: submitted a CLP, and treat with copaiba oil by subcutaneous injection. After the death of the histological analysis were performed. The Kaplan-Meier curves of surviving time were realized. RESULTS: All animals that received copaiba, regardless of the route used, survived longer when compared to the control group (p<0.0001), whereas the survival time ranged from 20 hours for the control group up to 32 hours for the animals of gavage group and 52 for subcutaneous group. The animals that received gavage copaiba lived about and about 20 hours unless the subcutaneous group (p=0.0042). There was no statistical difference when compared the intensity of inflammatory response (p>0.05). CONCLUSION: Prophylactic subcutaneous administration of copaiba in mice subjected to severe sepsis by cecal ligation and puncture, resulted in a survival time higher than non-use or use of this oil by gavage.
Acesso aberto (Open Access)
Efeito do tratamento com Euterpe Oleracea (Açaí) no processo de reparo do tendão de aquiles em ratos
(Universidade Federal do Pará, 2016-09-09) SILVA, Dlânio Gabriel Figuêredo; MORAES, Suellen Alessandra Soares de; http://lattes.cnpq.br/6278397231382779
Achilles tendon is the largest and strongest tendon in the human body, its excessive use induces microtrauma and activation of signaling pathways that lead to an inflammatory response. The ethanolic extract of Euterpe oleracea(açaí) is a natural product extracted from the fruit of the palm tree.Although evidence suggests an anti-inflammatory and antioxidant effect of this product, there is no data in the literature about such effects on tendon lesion. The aim of this study was to investigate the anti-inflammatory and pro-regenerative effects of ethanolic extract of Euterpe oleracea in a rat model of total Achilles tendon rupture. This study was approved by the Animal Research Ethics Committee (CEPAE-UFPA/206-14). The animals were divided into four groups (n = 24): control; vehicle (0.9% saline); E. oleracea extract (125 μg/mL ethanolic extract of Euterpe oleracea) and methylprednisolone (30 mg/ml). After the respective treatments, the tissue was analyzed at 7, 14 or 21 days post-injury (dpi) by immunohistochemistry with hematoxylin/eosin and collagen autofluorescence. Immunofluorescence for COX2 and measurement of nitrite levels by Griess method were performed at 7 dpi. Treatment with E. oleracea extract accelerated tissue organization and orientation of the cells, similarly to the anti-inflammatory steroid methylprednisolone. This natural product led to an early alignment in collagen fibers as well as in the overall matrix structure when compared to the other groups, which was observed at 7 dpi and maintained at both 14 and 21 dpi. Treatment with E. oleracea extract or methylprednisolone reduced COX2 labeling in comparison to the vehicle at 7 dpi. Reduction in nitrite tissue levels was observed at 7 dpi in groups treated with E. oleracea extract (20.80 ± 2.54 μm/ml) and methylprednisolone (19.40 ± 2.31 μm/ml) compared to vehicle group (29.33 ± 3.98 μm/ml). Treatment with E. oleracea extract improved tissue organization and reduced both COX2 labeling and nitrite levels, suggesting anti-inflammatory and antioxidant effects. Our findings highlight E. oleracea extract as a natural product with potential application in Achilles tendon repair.
Acesso aberto (Open Access)
Efeitos anti-inflamatórios e neuroprotetores do extrato de gergelim (Sesamum indicum L.) em um modelo experimental de lesão aguda da medula espinhal de ratos
(Universidade Federal do Pará, 2016-06-10) PENHA, Nelson Elias Abrahão da; LIMA, Rafael Rodrigues; http://lattes.cnpq.br/3512648574555468; LEAL, Walace Gomes; http://lattes.cnpq.br/2085871005197072
The spinal cord is a component of central nervous system (CNS) with crucial functions for locomotion, motor skills, somatosensory and authonomic control. Spinal injuries are among the more serious and debilitating pathological conditions to human health with large worldwide. The use of experimental models of spinal cord injury (SCI) is pivotal to understandthe SCI pathophysiology as well as search for treatments to minimize the neurological deficits and improve functional recovery. In this work, we aimed to investigate the neuroprotective and anti-inflammatory effects of supercritical gergelim (Sesamum indicum L.) extract in the acute phase of SCI in adult rats. Male Adult rats were submitted to spinal cord (SC) hemissection at T8. The sham (non lesioned) and control animals were treated with 5% tween(veicle), while treated animals received intraperitoneal (i.p) injections of Gergelim extract (150 mg/kg divided in two doses per day). Animals were allowed to recovery and were perfused at 1, 3 and 7 days post-lesion. 20 μm sections were obtained using a cryostat and stained with methylen blue, hematoxylin-eosin (HE), trichromic of Gomori and cresyl violet for gross histopathology. In addition, sections were immunolabeled with specific antibodies against neutrophils (anti-MBS-1) and activated microglia/macrophages (anti-ED1). The muscle force was assessed through electromiographic records performed in both control and treated animals at 1 and 7 days postlesion. The control animals presented progressive SC cavitation concomitant with neutrophil recruitment and microglia/macrophage activation. The treatment with gergelim extract induced tissue preservation and considerable decrease of neutrophil recruitment at 1 and 3 days, which was confirmed by quantitative analysis (ANOVA-Tukey, p<0.05). The gergelim treatment also decreased the microglia/macrophage activation at 7 days (ANOVA-Tukey, p<0.05). The electromiographic records revealed that the gergelim treatment improved the muscular force in about 50% compared to control animals. The results suggest that black gergelim seed extract is anti-inflammatory, neuroprotective and induces muscle force recovery in adults rats submitted to acute SCI. Future studies should confirm that a phytotherapic obtained from black sesame extract can be used as possible neuroprotective agent for human SCI.
Acesso aberto (Open Access)
Efeitos do transplante autólogo de células monocelulares da medula óssea após lesão incompleta da medula espinhal de ratos adultos
(Universidade Federal do Pará, 2017-03-30) SOUZA, Celice Cordeiro de; HAMOY, Moisés; http://lattes.cnpq.br/4523340329253911; LEAL, Walace Gomes; http://lattes.cnpq.br/2085871005197072
Spinal cord injury (SCI) causes permanent loss of neurological function below the level of injury, generating social and psychological physical consequences in patients. The pathophysiology of SCI involves complex processes, such as hemorrhage, excitotoxicity and inflammation, mainly generated by microglial cells. Despite advanced knowledge of pathological mechanisms, effective and approved therapeutic strategies for the treatment of lesions and their consequences are still lacking without serious adverse effects. Cell therapy may represent a good therapeutic strategy because it demonstrates good results in the modulation of the inflammatory environment of the lesion and by probable mechanisms of differentiation. In the present study, we investigated the action of bone marrow mononuclear cells (BMMC) in incomplete lesions (hemisection to the right of the spinal cord, T8-T9 segment) after 42 days of injury (chronic lesion). The cells were from the injured animal itself (autologous transplantation) and the transplantation was intramedullary, i.e. the cells were inserted near the site of the lesion. In the present study, the functional effects of transplantation were investigated through the BBB scale (Basso, Beatie and Bresnahan), which allows the motor function of the hind legs of the animals to be graded. The anti-inflammatory effects of BMMC were also investigated. Histological and immunohistochemical techniques using Cresila Violet staining and anti-ED-1 (microglial marker / activated macrophages) and anti-GFAP (fibrillar astrocyte marker) antibodies were used. Qualitative and quantitative analyzes were performed. For quantitative analysis, the number of field activated astrocytes and macrophages / microglia were counted using binocular microscope with counting gradient (0.0625mm2) in a 40x objective. The counting averages and the standard deviations obtained were plotted in Cartesian coordinates. The counting was as follows: on the right side of the spinal cord (lesion side) and three fields per medullary region (ventral funiculus - FV, dorsal funiculus - FD, lateral funiculus - FL, dorsal horn - CD, ventral horn - CV and intermediate gray matter-SCI), totaling 18 counting fields per section. Treatment with BMMC was not effective in improving the motor function of the injured animals when we compared the treated and untreated animals (means and standard deviations of the groups: false operated, n = 4, 21 ± 0, control, n = 4, 13,57 ± 3.88, treated, n = 5, 15.07 ± 3.46). In the qualitative analysis by means of the staining of Cresila Violet, treated animals presented better tissue preservation when compared to the untreated animals. In the quantitative analysis of microglial activation, we observed that treatment with BMMC reduced the activation of these inflammatory cells (control: 19.52 ± 7.79, treated: 10.04 ± 2.37), but did not significantly reduce the activation of the astrocytes (Mean of the groups: control 17.74 ± 2.757, treated 14.46 ± 5.283). The results suggest that further studies are needed to come up with an effective strategy for patients with SCI. A possible combined treatment with other strategies may turn out to be promising for patients' functionality.
Acesso aberto (Open Access)
Efeitos neurocomportamentais e no estresse oxidativo em ratos tratados com extrato etanólico de própolis amarela
(Universidade Federal do Pará, 2015) SILVEIRA, Cinthia Cristina Sousa de Menezes da; MAIA, Cristiane do Socorro Ferraz; http://lattes.cnpq.br/4835820645258101
Propolis is a resinous substance produced by bees that collect raw material from different parts of plants, through the addition of salivary secretions and wax. In Brazil, 13 types of propolis were chemically characterized. In the yellow propolis of Mato Grosso do Sul were identified 15 compounds, all belonging to the class of triterpenoids, and low levels of phenolic compounds and flavonoids. This work aims to conduct behavioral and biochemical assays with acute administration of yellow propolis ethanolic extract. 8 groups of male Wistar rats, 3 months, were used (n = 10 per group) and were divided into control (Tween 5%), positive control for anxiolytic activity (diazepam), positive control for antidepressant activity (fluoxetine), positive control for mnemonic effect (caffeine), 4 doses of the extract (1, 3, 10, 30mg/kg). The extract administration was performed acutely, intraperitoneally. Behavioral tests were open field, elevated plus maze, forced swimming and inhibitory avoidance. After the behavioral testing was performed to collect blood in the intracardiac area of the animals for determination of nitric oxide, malondialdehyde, catalase, superoxide dismutase and total antioxidant capacity. The results obtained in the open field test showed spontaneous locomotion preserved and anxiolytic-like activity, confirmed result with the elevated plus maze. In the forced swimming test, the yellow propolis ethanolic extract demonstrated action of antidepressant-like. In the inhibitory avoidance test showed mnemonic activity at 30 mg/kg. In the evaluation of oxidative biochemistry, the extract reduced the production of nitric oxide and malondialdehyde without changing level of total antioxidant, catalase and superoxide dismutase, induced by stress. With these results it is concluded that the yellow propolis ethanolic extract has anxiolytic, antidepressant, mnemonic and antioxidant activity.
Acesso aberto (Open Access)
Efeitos no comportamento motor após intoxicação subcrônica de metilmercúrio na presença de etanol (padrão binge) em ratas adolescentes à fase adulta
(Universidade Federal do Pará, 2015-11-06) OLIVEIRA, Aline do Nascimento de; MAIA, Cristiane do Socorro Ferraz; http://lattes.cnpq.br/4835820645258101
Exposure to methylmercury through the contaminated seafood diet, concomitant abusive alcohol intake, in binge pattern, is quite common in gold mining communities of gold extraction, especially in the Amazon. The association between these two neurotoxicantes is also evident among adolescent women and creates the need to understand its effects on the central nervous system, especially in motor coordination, balance and spontaneous locomotion, because the studies are advanced only for the effects of exposure in isolation. Therefore this study aims to evaluate the effects on motor behavior resulting of subchronic exposure to methylmercury in the presence of alcohol, in binge pattern, in adolescents female rats until early adulthood (37-72 postnatal day), through behavioral motors tests, like Open Field, Pole Test, Rotarod and Beam Walking Test. The testing occurred 24 hours after the last intoxication of rats, which received methylmercury (0.04 mg / kg / day) for 35 days, concomitant with alcohol (3g / kg / day), 3 intermittent days, 1 time per week (binge), totaling 5 binges. The results showed a decrease in spontaneous locomotion in Open Field test through the parameters of the total distance traveled and number of rearing. In the Pole test was increased fall time, evidencing the bradykinesia. In the Rotarod there was a decrease in latency in the first three exhibitions, as well as Beam Walking Test was increased latency and number of slips, especially in thinner beams, showing that subchronic exposure to methylmercury in the presence of alcohol, in the binge, in adolescent female rats was able to produce behavioral damages related to coordinating motor, balance and spontaneous locomotor activity.
Acesso aberto (Open Access)
Effect of andiroba oil on periodontitis in Wistar rats
(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2013-06) CARMONA, Glaucia Babeto; TEIXEIRA, Renan Kleber Costa; BRITO, Marcus Vinicius Henriques; PONTES, Flávia Sirotheau Corrêa; ANDRADE, Eloisa Helena de Aguiar; FONSECA, Felipe Paiva; COSTA, Ricardo Miranda Brito; CARVALHO, Francideise Martins
PURPOSE: To evaluate the effects of andiroba oil on the periodontitis in rats. METHODS: The periodontitis was induced by the placement of cotton ligatures around the cervix of the second upper molars on fifteen rats, and waiting fifty days. The animals were randomly distributed into three groups: saline group, andiroba oil group and meloxican group, differentiated by substance used in the treatment of periodontitis. The groups received the respective substance by gavage for seven days, after the periodontitis induced. It was analyzed the score of inflammatory cells and the measurement from the cemento-enamel junction to the bone crest. RESULTS: The andiroba oil group (p=0.008) and meloxican group (p=0.0347) show a less score of inflammatory cells than saline group, however there weren't difference between them (p=0.2754). Regarding the analysis of measurement from the cemento-enamel junction to the bone crest, there was no difference between groups studied (p=0.3451). CONCLUSION: Andiroba oil decreased the quantity of inflammatory cells, however, it didn't have an effect on the measurement of alveolar bone loss, like the treatment with Meloxican®.
Acesso aberto (Open Access)
Effect of copaiba oil in hepatic damage induced by acetaminophen in rats
(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2013-07) TEIXEIRA, Renan Kleber Costa; YAMAKI, Vitor Nagai; YASOJIMA, Edson Yuzur; BRITO, Marcus Vinicius Henriques
PURPOSE: To investigate the effects of copaiba oil on the hepatic damage induced by paracetamol. METHODS: Thirty six rats were distributed into six study groups (N=6): control group, that didn't receive the acetaminophen; Acetaminophen Group, that only received the acetaminophen; Prophylactic Copaiba Group 1, that received copaiba oil two hours before the acetaminophen; Prophylactic Copaiba Group 7, that received copaiba oil seven days, once by day, before the acetaminophen; Therapy Copaiba Group, that received the copaiba oil two hours afther the acetaminophen; and N-Acetyl-Cysteine Group, , that received the N-Acetyl-Cysteine two hours afther the acetaminophen. Euthanasia was performed after 24 hours. The serum levels of AST, ALT, alkaline phosphatase, GT, total bilirubin, direct bilirubin and indirect bilirubin and histological analisis were analized. RESULTS: The prophylactic copaiba group 7, therapy copaiba group and N-Acetyl-Cysteine Group showed amounts of AST and ALT similar to the control group; and the prophylactic copaiba group 1 showed similar levels to the acetaminophen group. There was no significant difference between the groups regarding the amount of alkaline phosphatase and GT (p>0.05). The therapy copaiba group showed the highest levels of bilirubin and was statistically different from the other groups (p<0.01) and this increased the costs of direct bilirubin. Regarding histopathology, the oil of copaiba administered prophylactic or therapeutic form for 7 days could decrease the amount of necrosis and inflammatory infiltrate. CONCLUSION: Copaiba oil administered prophylactically for seven days, and therapeutic could reduce liver damage caused by paracetamol similarly N-Acetyl-Cysteine, however, when treated with copaiba therapeutically showed increases in bilirubin, costs increasing fraction indirect.
Acesso aberto (Open Access)
Fenótipos microgliais e tratamento com minociclina após isquemia focal induzida por microinjeções de endotelina-1 no córtex motor de ratos adultos
(Universidade Federal do Pará, 2016-12-23) DIAS, Michelle Nerissa Coelho; LEAL, Walace Gomes; http://lattes.cnpq.br/2085871005197072
Microglial cells are fundamental components of the innate immune system that continually make a complete scan of the neural parenchyma in search of subtle tissue changes for the preservation of tissue integrity. These resident macrophages of the central nervous system (CNS) correspond to about 20% of the encephalic cell population. In acute and chronic neural disorders, including brain and spinal cord injury, experimental stroke, Alzheimer's, Parkinson's and Huntington's disease, microglial cells are activated, which is reflected in morphological and biochemical changes. In these diseases, it is believed that microglial activation contributes to both neuroprotection and exacerbation of the injury process. Several experimental evidences suggest that excessive microglial activation may contribute to the increase of the injury process after experimental stroke. However, our previous studies suggest that microglial cells may release trophic factors after experimental stroke in anatomically distinct regions of the microglial population with deleterious phenotypes. There are no studies that have described the reactivity patterns of the different microglial phenotypes after experimental ischemia. In the present project, we will investigate the patterns of activation of microglial cells presenting beneficial and harmful phenotypes, evaluating which microglial populations are inhibited by tetracycline minocycline after focal cortical ischemia. The animals were submitted to focal ischemia in the motor cortex by microinjections of 80 pMol of endothelin-1 (ET- 1). They were sacrificed 7, 14 and 30 days after ischemic induction. The immunohistochemistry technique for the observation of neuronal loss (NeuN +) and double immunofluorescence to evaluate the density of M1 and M2 microglial cells in the lesioned area was used. Statistical analysis of NeuN+ cell density was performed by the Student's t-test from the 7-day of control and treated groups while the analysis of the M1 and M2 microglial cells were done by the analysis of variance in the 07, 14 and 30 control groups, adopting in all tests the level of significance P <0.05. A preservation in the number of neurons in the injured parenchyma of the animals treated with minocycline was confirmed. A decrease in the number of M1 microglial cells in minocycline-treated animals was observed, suggesting that the drug may present effects on expression pathways of M1 microglial phenotypes. However, when the animals of the control group of 07, 14 and 30 are compared, there is an increase in the number of this M1 phenotype that extends from day 7 to day 30. We conclude that there is a neuroprotective effect of the drug minocycline when associated to stroke, suggesting that this drug may be involved in the modulation of microglial phenotypes requiring further studies on its function in the pathways of expression of these phenotypes.
Acesso aberto (Open Access)
Imunoreatividade para os receptores de neurotrofinas P75NTR e TrkA na zona subventricular de ratos adultos após isquemia estriatal
(Universidade Federal do Pará, 2015-08-21) TAVARES, Patrycy Assis Noronha; LIMA, Rafael Rodrigues; http://lattes.cnpq.br/3512648574555468; LEAL, Walace Gomes; http://lattes.cnpq.br/2085871005197072
Neurotrophins are growth factors expressed by cells of the nervous system both during development and in adulthood. The Nerve Growth Factor (NGF, the English- Nerve Growth Factor), brain-derived neurotrophic factor (English- BDNF- of Brain-Derived Neurotrophic Factor), Neurotrophin-3 (NT-3), Neurotrophin-4/5 ( NT-4/5), have many functions related to aging and response of nervous tissue to the pathology such as vascular accident (CVA). In this pathology, the increase of the neurotrophin expression can interfere with the degree of neurogenesis in the sub-ventricular zone (SVZ) and redirect the rostral migratory flow of Adult Neural Stem Cells (CTNAs) to the ischemic region. The presence of neurotrophin receptors TrkA and p75NTR in the CTNAs of SVZ indicates that they may participate in the regulation of neurogenesis in this region. Here we describe the influence of an experimental ischemia by microinjection of a vasconstritor Endothelin-1 peptide, which is restricted to the striatum adjacent SVZ; on the pattern of immunoreactivity for TrkA and p75NTR receptors in different survival times. The histopathological pattern of ischemic striatum and the cytoarchitecture of the SVZ, followed by immunohistochemical analysis to the receptors were analyzed. Numerous p75NTR + cells were found in the ipsilateral SVZ and against the injection site, with had a reduction in immunoreactivity at first and third day after ischemia. Few TrkA + cells were found in SVZ of both groups, however, many TrkA + axonal terminals were saw in the ischemic ipsilateral SVZ. Soon after the ischemic process, there was thickening of the SVZ, the concomitant reduction in immunoreactivity for p75NTR and TrkA + arisings of axonal terminals.
Acesso aberto (Open Access)
Influência da glutationa (GSH) nos registros eletrorretinográficos de ratos wistar adultos
(Universidade Federal do Pará, 2014-03-26) RABELO, Natielle Ferreira; ROCHA, Fernando Allan Farias; http://lattes.cnpq.br/3882851981484245; GOMES, Bruno Duarte; http://lattes.cnpq.br/4932238030330851
Glutathione (GSH) is a molecule involved in many biological processes, known primarily for its antioxidant. Currently , this tripeptide composed of glutamate , cysteine and glycine has been widely studied for its possible action as a neurotransmitter in the CNS and nuromodulador . The present study evaluated the action of this molecule through the electroretinogram, to evaluate the mass response of the retina, produced after light stimulation. Methods: GSH intravitreal injections were performed at different concentrations (1 , 5 and 10 mM) and PBS ( control) in Wistar rats. The assessment protocol consisted of 6 stimuli in different conditions of adaptation: Scotopic response of rods and Scotopic maximal response after dark adaptation of at least 12h ; photopic cone response after 10 min of adaptation to the course, with the use of filters subpopulations for the evaluation of UV and S cones , and the response to the stimulus flicker at 12 Hz. The main parameters were the amplitudes of the waves -a and- b and their implicit time, and b-wave amplitude of the flicker. RESULTS: The results show changes in response, with decrease in b-wave amplitude of the ERG in all stimuli . When done the test of multiple comparisons, differences were observed between the control group and 5 mM GSH and 10 mM GSH . Changes in the amplitude of a-wave only observed in Scotopic maximal response, with a significant decrease in the amplitude. The latency time of the responses showed no changes in any individual group. DISCUSSION: The retinal Muller cells contains a large amount of GSH and may act actively in the modulation of glutamate and glycinergic responses, also has been shown that GSH induces the release of GABA in the retina, which may explain the decrease of the amplitudes observed by over- activation of an inhibitory pathway. CONCLUSION: The present work supporting the hypothesis that GSH acts as a neuromodulator in the CNS, with significant inibitory changes in the retina after administration .
Acesso aberto (Open Access)
Inibição nitrérgica local favorece o processo de regeneração do tendão de aquiles em ratos submetidos à tenotomia
(Universidade Federal do Pará, 2011-05-27) MORAES, Suellen Alessandra Soares de; SILVA, Anderson Manoel Herculano Oliveira da; http://lattes.cnpq.br/8407177208423247
The tendon injuries prevalence has been increased usually by repetitive movements in the occupational and recreational activities of society. The main features this injury involve healing dysfunction and loss of extracellular matrix. At this tissue, the extracellular matrix is basically made of type I collagen and the loss of this protein associated with problems in the remodeling have been considered the major responsible for the symptomatic and functional effects of injury. Additionally the literature reports the nitric oxide synthase expression was up-regulated throughout the repair process. At this context the propose of this work is investigated the nitrergic local inhibition in tissue and functional recovery after tendon injury. We used a experimental model of Achilles tendon rupture for establish pathophysiological changes similar to chronic tendinopathy. The animals were divided into experimental groups control, injury+vehicle (saline, 0,9%), injury+L- Nω-nitro-L-arginine methyl ester (L-NAME, 5mM) and injury+sodium nitroprusside (SNP, 3mM), which were followed until the 21º day, when were killed to collect samples. In order to access nitric oxide production Griess nitrite assay was used. Functional recovery was calculated by Achilles Functional Index (AFI) in 0, 7, 14 and 21 days. Tendons were also processed for histomorphological and autofluorescence analysis. The body weight gain was also evaluated. We characterized the effect of drugs about tissue without stronger systemic influences by maintenance of body weight and plasmatic levels of nitrite. The L-NAME led to significant decrease in the cellular density, vessel formation between collagen network, accelerated the tissue organization and restored early the functional pattern at 21 days after injury. On the other hand, the treatment with SNP and vehicle remained the tissue disorganization and low functional performance. Taken together our results suggest a positive effect of local suppression of NOS after rupture for tissue remodeling, contributing to tendon regeneration.
Acesso aberto (Open Access)
Lesão intestinal após isquemia-reperfusão: estudo comparativo usando sal tetrazólico (MTT) e histologia
(Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2001-03) BRITO, Marcus Vinicius Henriques; ARAÚJO, Marialva Tereza Ferreira de; ACÁCIO, Glayce June Sasaki; ACÁCIO, Glayce Josy Sasaki; REIS, José Maciel Caldas dos
Many methods are used to evaluate ischemia reperfusion injury, but the most employed one is the histological study. However, it only demonstrates on mucosal tunic, the index of lesion and morphologic preserved cells, but not the index of viable functional cells, present in the sample. With this purpose, a colorimetric method was used, employing Methyl Thiazolyl Blue (MTT). The experiment was conducted in 30 Wistar male rats, distributed in 3 groups: Group Control (GC), Group ischemia and reperfusion-1 (GIR-1) and Group ischemia and reperfusion-3 (GIR-3), with 10 animals each. The Groups GIR-1 and GIR-3 were submitted to intestinal ischemia for 30 minutes by a false ligature of superior mesenteric artery, and submitted to euthanasia after 1 and 3 days of reperfusion, when material was picked for absorbency and histological procedures. It was observed a smaller proportion of viable cells and a larger degree of mucosal lesion in GIR-3 group (p<0.05), while GC group was the one with the larger proportion of viable cells and smaller degree of the mucosal injury (p<0.05). This way we concluded that MTT is as effective and reliable as the histological study at evaluating alterations produced by intestinal ischemia-reperfusion.