Resumo
Objetivou-se avaliar a utilização da placa aquecedora, em substituição ao banho-maria, no teste de termorresistência (TTR) de espermatozoides de carneiros após a criopreservação. Foram coletados 10 ejaculados de três carneiros adultos (n=30), por meio de vagina artificial para ovinos. Em seguida, foram diluídos em TrisGema de ovo, a uma concentração final de 200 x106 sptz/mL, e submetidos á curva de resfriamento, para posterior criopreservação em palhetas em nitrogênio líquido. Após descongelação, as amostras foram analisadas quanto à integridade de membrana, de acrossoma e atividade mitocondrial. O sêmen então foi dividido em dois tubos e submetido ao TTR, um em banho-maria e outro em placa aquecedora, e, ainda, avaliado a cada 30 minutos, do tempo zero (pós-descongelação) até 90 minutos de incubação, a 37 °C, quanto à motilidade espermática e à motilidade progressiva. As variáveis foram submetidas à análise de variância e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Após o processo de congelação/descongelação, os espermatozoides apresentaram baixo percentual de integridade de membrana e elevado percentual de atividade mitocondrial e integridade do acrossoma. Não foi observada diferença na motilidade espermática nem na motilidade progressiva ao longo do TTR, quando comparados os espermatozoides que foram incubados em banho-maria aos incubados em placa aquecedora durante o período de 90 minutos. A placa aquecedora pode ser utilizada como meio de incubação dos espermatozoides de carneiros em substituição ao banho-maria.
The objective was to evaluate the use of the hot plate to replace the water bath in the thermo resistance test of ovine sperm after cryopreservation. Ten ejaculates were also collected from three adult sheep (n=30), by means of artificial sheep vagina. The collected samples were diluted in Tris-Egg Yolk, at a final concentration of 200 x106 sptz/mL and subjected to a cooling curve for subsequent cryopreservation in liquid nitrogen straws. Immediately after thawing, the samples were analyzed for membrane and acrosome integrity, and mitochondrial activity. The semen was then divided into two tubes and submitted to TTR, one in a water bath and the other in a hot plate, and evaluated every 30 minutes, from time zero (post-thaw) until 90 minutes of incubation at 37 °C, for sperm motility and progressive motility. The variables were subjected to analysis of variance and the means were compared using the Tukey test at 5% probability. After the freeze/thawing process, sperm showed a low percentage of membrane integrity, high percentage of mitochondrial activity, in addition to maintaining the integrity of acrossome. No difference was observed in sperm motility nor progressive motility, along the TTR, when comparing the sperm that were incubated in a water bath in relation to those incubated in a hot plate during the period of 90 minutes. The heating plate can be used as a means of incubating sheep sperm in replacement of the water bath.
Assuntos
Animais , Ovinos , Criopreservação/veterinária , Equipamentos de Laboratório , Termotolerância , Coleta de Tecidos e Órgãos/veterináriaResumo
The swimming has a number of physiological benefits, among which we can mention the increased resistance to the perception of thermal stimuli. The thermal sensitivity is designated as responsive to rising temperature, harmful heat, decrease the temperature and harmful cold. The thermal and painful sensations are transmitted to the central nervous system via axons C, Aδ. The heat-sensitive fibers C are called mecanotermossensíveis C fibers, which require different membrane receptors to make the distinction between various sensory thresholds. These receptors are called channels TRP (transient receptor potential) and are responsible for performing the transduction of thermal signals. The termocepção can be measured by the hot plate test based on the response latency to a given adverse thermal stimulus. Objectives: to determine the thermal sensitivity in rats submitted to swimming. Methods: This study was approved by the Ethics Committee for the Use of Animals (CEUA) of the State University of Ceará (UECE), Official Letter No. 12725887-0. 16 female Wistar rats were used ± 8 weeks, divided into two groups: control (C) and swimming (N). The animals swimming starting time duration of 3 minutes for the first week and reaching 36 minutes at the end of the second week with a 5% body weight load tied to the tail, to avoid floating. The exercises in the water were carried out by the morning shift, six days a week and a weekly rest. The animals were then immediately dried by a hot air jet device (sized hair dryer). Thermal sensitivity was evaluated using the hot plate test at 50°C is considered as a valid positive response and the heel of the animal licks its hind legs and cleaning of the animals forepaws. The results were analyzed by comparing an average between the two groups tested by one-way ANOVA analysis. Statistical analysis was performed using t test for independent samples, assuming significance of p <0.05. Results and Discussion: As a result, one can observe a significant increase (p = 0.014) in response time to thermal stimulation of the swimming group (5.875 ± 1.060 N = 8) compared to the control group (2.375 ± 0.962 N = 8). These results confirm previous studies, which show that swimming is able to increase the nociceptive threshold in rodents, suggesting that exercise the aquatic environment is able to reduce the activation of TRPV1 channels, which are only activated at temperatures between 42 and 52 ° C. This mechanism might explain the increased latency response comparing the swimming group with the control group. Conclusion: The data demonstrate that swimming increased tolerance to thermal stimuli, which produces a positive effect on the animals, it increases the selectivity of the intensity of painful stimuli perceived by the body.
Assuntos
Animais , Ratos , Natação , Sensação Térmica , TermorreceptoresResumo
The swimming has a number of physiological benefits, among which we can mention the increased resistance to the perception of thermal stimuli. The thermal sensitivity is designated as responsive to rising temperature, harmful heat, decrease the temperature and harmful cold. The thermal and painful sensations are transmitted to the central nervous system via axons C, Aδ. The heat-sensitive fibers C are called mecanotermossensíveis C fibers, which require different membrane receptors to make the distinction between various sensory thresholds. These receptors are called channels TRP (transient receptor potential) and are responsible for performing the transduction of thermal signals. The termocepção can be measured by the hot plate test based on the response latency to a given adverse thermal stimulus. Objectives: to determine the thermal sensitivity in rats submitted to swimming. Methods: This study was approved by the Ethics Committee for the Use of Animals (CEUA) of the State University of Ceará (UECE), Official Letter No. 12725887-0. 16 female Wistar rats were used ± 8 weeks, divided into two groups: control (C) and swimming (N). The animals swimming starting time duration of 3 minutes for the first week and reaching 36 minutes at the end of the second week with a 5% body weight load tied to the tail, to avoid floating. The exercises in the water were carried out by the morning shift, six days a week and a weekly rest. The animals were then immediately dried by a hot air jet device (sized hair dryer). Thermal sensitivity was evaluated using the hot plate test at 50°C is considered as a valid positive response and the heel of the animal licks its hind legs and cleaning of the animals forepaws. The results were analyzed by comparing an average between the two groups tested by one-way ANOVA analysis. Statistical analysis was performed using t test for independent samples, assuming significance of p <0.05. Results and Discussion: As a result, one can observe a significant increase (p = 0.014) in response time to thermal stimulation of the swimming group (5.875 ± 1.060 N = 8) compared to the control group (2.375 ± 0.962 N = 8). These results confirm previous studies, which show that swimming is able to increase the nociceptive threshold in rodents, suggesting that exercise the aquatic environment is able to reduce the activation of TRPV1 channels, which are only activated at temperatures between 42 and 52 ° C. This mechanism might explain the increased latency response comparing the swimming group with the control group. Conclusion: The data demonstrate that swimming increased tolerance to thermal stimuli, which produces a positive effect on the animals, it increases the selectivity of the intensity of painful stimuli perceived by the body.(AU)
Assuntos
Animais , Ratos , Natação , Sensação Térmica , TermorreceptoresAssuntos
Animais , Ovinos , Reprodução , Sêmen , Aquecedores , Criopreservação/veterinária , Técnicas Reprodutivas/veterináriaAssuntos
Animais , Ovinos , Sêmen , Reprodução , Técnicas Reprodutivas/veterinária , Criopreservação/veterinária , AquecedoresResumo
A Luehea divaricata é uma planta usada na medicina popular brasileira com finalidades diversas, sobretuto anti-inflamatória, antianêmica e diurética. Considerando-se os seus usos etnofarmacológicos, realizou-se este estudo com o objetivo de conhecer os constituintes químicos e a toxicidade aguda e subcrônica do extrato etanólico formulado a partir das cascas do caule de L. divariacata (EtOH-Ld), bem como a atividade antinociceptiva das frações acetato (AcOEt) e aquosa do EtOH-Ld, de modo a possibilitar informações sobre os seus possíveis mecanismos de ação. O estudo fitoquímico evidenciou, nas frações AcOEt e aquosa, a presença de taninos, antocianidinas, antocianinas, fenóis, leucoantocianidinas, saponinas, triterpenos e alcaloides. Na verificação da toxicidade aguda, dois grupos de camundongos, cada um com seis animais, foram tratados com EtOH-Ld, nas dosagens de 300 e 2000 mg/kg, respectivamente. E na toxicidade subcrônica, quatro grupos com seis ratos cada um, foram tratados com o veículo e com o EtOH-Ld nas dosagens de 100, 500 e 1000 mg/kg. Para avaliar a atividade antinociceptiva das frações AcOEt e aquosa realizaramse os seguintes testes: formalina e placa quente, utilizando camundongos Swiss machos, divididos em seis grupos de seis animais, que foram tratados com ambas as frações, nas dosagens de 100 e 200 mg/Kg, por via oral. Para verificar a participação dos sistemas serotoninérgico, colinérgico muscarínico e dopaminérgico, o que permite inferência sobre o mecanismo de ação, utilizou-se o teste de formalina. Os resultados foram submetidos a análise de variância e comparação de médias pelo teste de Tukey (p<0,05). Em relação à toxicidade aguda, os animais não expressaram alterações comportamentais em nenhum grupo e, na avaliação da toxicidade subcrônica, não foram vistas alterações dignas de nota no fígado, baço e rins, bem como, não foram evidenciadas diferenças entre os grupos tratados e não tratados no perfil bioquímico (p<0,05). O EtOH-Ld, nas diferentes doses estudadas, apresentou atividade antinociceptiva nas frações acetato e aquosa, sendo mais significativa (p>0,05) a fração aquosa na dosagem 200 mg/kg, nos testes de formalina e placa quente. A fração aquosa (200 mg/kg) do EtOH-Ld, mostrou melhor resposta pela via colinérgica muscarínica. Assim, pode-se concluir que o EtOH-Ld não apresenta manifestações clínicas de toxicidade aguda e crônica, sendo que a fração aquosa, na dosagem de 200 mg/kg, proporciona melhor efeito antinociceptivo.
The Luehea divaricata is a plant used in Brazilian folk medicine for various purposes, sobretuto anti-inflammatory, diuretic and antianemic. Considering their ethnopharmacological uses, took place this study in order to know the chemical constituents and acute toxicity and subchronic the ethanol extract made from the stem bark of L. divariacata (EtOH-Ld) and the antinociceptive activity of fractions acetate (EtOAc) and the aqueous EtOH-Ld, to enable information on their possible mechanisms of action. The phytochemical study showed, in EtOAc and aqueous fractions, the presence of tannins, proanthocyanidins, anthocyanins, phenolics, leucoanthocyanidins, saponins, triterpenes and alkaloids. In the verification of acute toxicity, two groups of mice, each with six animals were treated with EtOH-Ld at the dosages of 300 and 2000 mg/kg, respectively. The subchronic toxicity, four groups of six rats each, were treated with vehicle or EtOH-Ld at the dosages of 100, 500 and 1000 mg/kg. To evaluate the antinociceptive activity of AcOEt and aqueous fractions were performed the following test: hot plate and formalin using male Swiss mice were divided into six groups of six animals that were treated with both fractions at the dosages of 100 and 200 mg/kg, orally. To check the contribution of serotonergic systems, muscarinic cholinergic and dopaminergic, which allows inference about the mechanism of action, we used the formalin test. The results were submitted to analysis of variance and comparison of means by Tukey test (p<0,05). Regarding the acute toxicity, the animals did not express behavioral changes in either group, and in assessing the subchronic toxicity, were not seen changes worthy of note in the liver, spleen and kidneys as well, no differences were observed between the treated groups and not processed in the biochemical profile (p<0,05). EtOH-Ld in different doses studied showed antinociceptive activity in the fractions acetate and water, and most significant (p>0,05) on the aqueous fraction dosage 200 mg/kg in the formalin test, hot plate. The aqueous fraction (200 mg/kg) of EtOH-Ld showed better response pathway by muscarinic cholinergic receptor. Thus, it can be concluded that the EtOH-Ld presents no clinical manifestations of acute and chronic toxicity, and the aqueous fraction, at a dose of 200 mg/kg, provides better the antinociceptive effect.