Efeitos renais promovidos pelo veneno de serpente Bothrops atrox e a produção de óxido nítrico

Abstract

Snakes of the genera Bothrops are the most responsible for ophidian accidents occurred in Brazil, representing a serious public health problem due to their frequency, morbity and mortality rates. Envenomation caused by the species Bothrops atrox leads to systemic complication, which is responsible for the preliminary cause of death after ophidian accident. The aim of this work was to evaluate the pharmacological effects of the crude venom of Bothrops atrox (VBA), in perspective of elucidating the physiopathological mechanisms occurred in the tissues. First of all, the actions of VBA were evaluated in the renal perfusion system, in which the organ was exposed to the venom of B. atrox to evaluate possible renal parameters alterations. After the renal perfusion, the kidneys were submitted to histological analysis. The parameters were analyzed by ANOVA and Student t-test, with p<0,005. The results showed that VBA decreased the perfusion pressure (PP) and renal vascular resistance (RVR) significantly as in contrast with the urinary flow (UF) and glomerular filtration rate (GFR) which had a significant increase. It was observed both increase and reduction of the percentage of chloride and sodium transport, respectively. The histological alterations of the perfused kidneys were discrete, indicating the presence of proteinaceous substance in the glomeruli and tubules. An investigation was made - in an in vivo experiment - into the participation of nitric oxide (NO) in the systemic effects induced by VBA. There was an increase of the nitrite production in the blood of animals that received the VBA treatment. Pharmacological blockade with L-NAME was carried out and the increase of the nitrite production was nullified. Due to these results, we conclude that VBA causes alterations on renal parameters and it induces increase of the oxide production.