The renal effects and initial characterization of venom from Philodryas nattereri Steindachner, 1870

The venom of the snake Philodryas nattereri is a mixture of proteins and toxic peptides with several important local and systemic actions, which are similar to those occurring in Bothrops snake bites. The mechanisms involved in the local and systemic actions of this venom are unknown. The aims of the work were to initial characterization of P. nattereri venom and investigate the effects of the poison in the renal perfusion system and in cultured renal tubular cells of the type MDCK (Madin-Darby canine kidney). The P. nattereri venom is composed majority of proteins (86.3%) and this poison promoted changes in all the evaluated renal parameters, mainly decreasing renal perfusion pressure (PP) and renal vascular resistance (RVR) and increasing urine flow (UF) and glomerular filtration rate (GFR). The most relevant result was that this venom was highly detrimental to the renal tubules independent of the PP reduction, which was shown by a decrease in sodium (Na⁺), potassium (K⁺) and chloride (Cl^-) electrolyte transport in the studied concentrations. The glomeruli and tubules contain protein bodies and blood extravasation, which were observed by histological analysis. The venom of P. nattereri reduced viability of the MDCK cells only at high concentrations (50 and 100 μg/mL) with an IC₅₀ of 169.5 μg/mL.