RESUMO
Many studies have reported the occurrence of lethal acute renal failure after snakebites. The aim of the present investigation was to determine alterations in renal function produced by Crotalus durissus terrificus venom and crotoxin as well as the histological alterations induced by these venoms. Isolated kidneys from Wistar rats weighing 240 to 280 g were perfused with Krebs-Henseleit solution containing 6 g percent of previously dialyzed bovine serum albumin. The effects of Crotalus durissus terrificus venom and crotoxin were studied on glomerular filtration rate (GFR), urinary flow (UF), perfusion pressure (PP) and percentage sodium tubular transport ( percentTNa+). The infusion of Crotalus durissus terrificus venom (10 æg/ml) and crotoxin (10 æg/ml) increased GFR (control80 = 0.78 + or - 0.07, venom80 = 1.1 + or - 0.07, crotoxin80 = 2.0 + or - 0.05 ml g-1 min-1, P<0.05) and UF (control80 = 0.20 + or - 0.02, venom80 = 0.32 + or - 0.03, crotoxin80 = 0.70 + or - 0.05 ml g-1 min-1, P<0.05), and decreased percentTNa+ (control100 = 75.0 + or - 2.3, venom100 = 62.9 + or - 1.0, crotoxin80 = 69.0 + or - 1.0 ml g-1 min-1, P<0.05). The infusion of crude venom tended to reduce PP, although the effect was not significant, whereas with crotoxin PP remained stable during the 100 min of perfusion. The kidneys perfused with crude venom and crotoxin showed abundant protein material in the urinary space and tubules. We conclude that Crotalus durissus terrificus venom and crotoxin, its major component, cause acute nephrotoxicity in the isolated rat kidney. The current experiments demonstrate a direct effect of venom and crotoxin on the perfused isolated kidney