Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The renal kinetics of Bothrops alternatus venom (0.8 mg/kg, i.v.) was studied in conscious male Wistar rats. Blood, urine and renal tissue samples were collected at various intervals after envenoming. Venom was quantified by ELISA in serum, renal tissue and urine. Urine volume was measured and the urine assayed for urobilinogen, glucose, bilirubin, ketones, urine specific gravity, occult blood, pH, protein, nitrite and leucocytes. Circulating venom showed biexponential kinetics, with no venom being detected after 7 days post-venom. Venom was detected in renal tissue 30 min post-venom but decreased progressively thereafter, in parallel with serum venom concentrations. Immunohistochemistry detected venom in glomeruli, proximal and distal tubules, and vascular and perivascular tissue. Venom was detected in urine 3, 6 and 24 h post-venom. Oliguria occurred 3 h to 7 days post-venom, urine acidification occurred 3-6 h post-venom, urine specific gravity increased in the first 3 h and proteinuria was also greatest in this period. Creatinine clearance decreased progressively until 24-48 h post-venom, then returned to normal. Glucose, ketones, leucocytes and occult blood were detected mainly during the first 6 h post-venom. These results indicate reversible alterations in renal function, with renal elimination of the venom. (C) 2009 Elsevier Ltd. All rights reserved.5541700470480Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)