Venom of the South American rattlesnake, Crotalus durissus terrificus (Cdt), presents myotoxic and neurotoxic outcomes, but reports on its effects on the liver are scarce. This study examined the hepatotoxicity resulting from Cdt venom administration (100, 200 and 300 µg/kg) in male Wistar rats. Animals were studies at 3, 6, 9 and 12 hours after venom injection. The hepatotoxicity was assessed through serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), gamma glutamyl transferase (GGT), bilirrubin and also by histopathological evaluation. All the different concentrations of Cdt venom resulted in increased levels of hepatic enzymes, when compared with the control group, except for the 100 µg/kg dose, which presented normal levels at 9 and 12 hours after venom administration. Bilirrubin levels remained unchanged by Cdt venom. Histological analysis revealed endothelial damage, inflammatory cell infiltration, as well as sinusoidal and portal congestion. Based on these observations, we may conclude that Cdt venom causes dose- and time-dependent hepatic damage in rats, characterized by elevated hepatic enzyme levels and histological alterations.

The present study aimed to assess the effects of low-level laser (660 nm) on myonecrosis caused by the insertion of Bothrops neuwiedi venom in the gastrocnemius muscle of rats. Male Wistar rats were divided into three groups (n = 24 each): Group S (0.9% saline solution); Group V (venom) and Group VLLL (venom plus low-level laser). These categories were subdivided into four additional groups (n = 6) based on the euthanasia timing (3 hours, 24 hours, 3 days and 7 days). The groups V and VLLL were inoculated with 100 µL of concentrated venom (40 µg/mL) in the gastrocnemius muscle. The muscle was irradiated using a gallium-aluminum-arsenide laser (GaAlAs) at 35 mW power and 4 J/cm² energy density for 3 hours, 24 hours, 3 days or 7 days after venom inoculation. To evaluate the myotoxic activity of the venom, CK activity was measured and the muscle was histologically analyzed. The low-level laser reduced venom-induced CK activity in the groups euthanized at 3 hours, 24 hours and 3 days (p < 0.0001). Histological analysis revealed that low-level laser reduced neutrophilic inflammation as well as myofibrillar edema, hemorrhage and myonecrosis following B. neuwiedi envenomation. These results suggest that low-level laser can be useful as an adjunct therapy following B. neuwiedi envenomation.