Renal and vascular effects of Crotalus durissus cumanensis venom and its crotoxin fraction

Abstract

Abstract:In this study, we evaluated the actions of Crotalus durissus cumanensis venom (CDCmV), and its crotoxin (Crtx) fraction, on renal and vascular functions in Wistar rats. In isolated perfused kidneys, CDCmV (10 µg/mL) significantly increased the perfusion pressure (PP) from 110.7 ± 2.4 to 125.3 ± 2.8 mmHg after 30 minutes. This effect was accompanied by an increased renal vascular resistance (RVR) from 5.4 ± 0.1 to 6.2 ± 0.2 mmHg/mL.g ). Both CDCmV and Crtx reduced the percentage of tubular transport of sodium, chloride and potassium. The cytotoxicity of these substances against MDCK cells was tested by the MTT method: only CDCmV caused a decrease in the cell viability with an IC 50 of 5.4 µg/mL. In endothelium-intact isolated aortic rings, CDCmV (0.1 to 30 µg/mL) increased the sustained phenylephrineinduced contraction to a value of 130.0 ± 6.6% of its corresponding control, but showed a relaxant effect in endothelium-denuded preparations. Similar results were observed in aortic rings contracted with potassium (40 mM). Crtx was ineffective in aortic ring assays. Thus, it is reasonable to suggest that the renal effects induced by the CDCmV may be due to its influence on the endothelium's ability to release factors that can alter the contractile behavior of vascular smooth muscle. In conclusion, CDCmV is toxic to kidney cells. It changes parameters of the renal function including the glomerular filtration rate, renal vascular resistance and tubular transport. The actions induced by CDCmV also involve endothelium-dependent vasoactive properties. Their effects may be only partially attributed to Crtx.

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

“…Th results of cytotoxic effects showed that the venom was toxic to cells because it significantly reduced viability in concentrations of 50 and 100 mg/mL compared to the control with an IC 50 of 169.5 μg/mL. This value for IC 50 is higher in relation of others species of snakes, such as Bothrops leucurus and Crotalus durissus cumanensis with 1.25 and 5.38 μg/mL, respectively [22] , [23] .…”

Effects of the Heterodimeric Neurotoxic Phospholipase A2 from the Venom of Vipera nikolskii on the Contractility of Rat Papillary Muscles and Thoracic Aortas

“…On the other hand, in a more recent study, no effects were observed 12 h after treating rat hearts with crotoxin [ 30 ]. The data on crotoxin’s vascular effects are also inconsistent; while in one work, it was shown that crotoxin induced contractions in Sprague Dawley rat ARs both with and without an endothelium [ 31 ], no effect of this toxin in AR assays was observed in another study [ 32 ]. To clarify this issue, we decided to study the effects of the heterodimeric PLA 2 HDP-1, which is homologous to crotoxin.…”