Effects of Crotalus durissus collilineatus venom in the isolated rat kidney

Abstract

Ophidian accidents caused by the subspecies Crotalus durissus are responsible for high morbity and mortality rates. Acute renal failure is a common complication observed in these accidents. The aim of the present study was to investigate the renal effects promoted by the venom of C. d. collilineatus and its fractions, crotoxin and phospholipase A 2. C. d. collilineatus (Cdc; 30 μg mL −1), crotoxin (CTX; 10 μg mL −1) and phospholipase A 2 (PLA 2; 10 μg mL −1) were tested in isolated rat kidney. The first 30 min of each experiment were used as an internal control and Cdc or its fractions, CTX and PLA 2 were added to the system after this period. All experiments lasted 120 min. The venom of Cdc decreased perfusion pressure (PP; control 120=110.3±3.69 mmHg; Cdc 120=96.7±8.1 mmHg), renal vascular resistance (RVR; control 120=6.42±0.78 mmHg mL g −1 min −1; Cdc 120=4.8±0.56 mmHg/mL g −1 min −1), urinary flow (UF; control 120=0.19±0.03 mL g −1 min −1; Cdc 120=0.12±0.01 mL g −1 min −1), and glomerular filtration rate (GFR; control 120=0.79±0.07 mL g −1 min −1; Cdc 120=0.53±0.09 mL g −1 min −1), but had no effect on the percent of sodium tubular transport (%TNa +), percent of chloride tubular transport (%TK +) and percent of potassium tubular transport (%TCl −). CTX and PLA 2 reduced the GFR, while UF, PP and RVR remained stable during the full 120 min of perfusion. Crotoxin administration also diminished the %TK + (control 120=69.94±6.49; CTX 120=33.28±4.78) and %TCl − (control 120=79.53±2.67; CTX 120=64.62±6.93). PLA 2 reduced the %TK +, but exerted no effect on the %TNa + or on that of TCl −. In conclusion, the C. d. collilineatus venom altered the renal functional parameters evaluated. We suggest that crotoxin and phospholipase A 2 were involved in this process, since the renal effects observed would be due to the synergistic action of the components of the venom.