RESUMO
Venoms from eight medically important snake species including three sea snake species, belonging to families Viperidae and Elapidae, were tested for lethal, hemolytic [direct and indirect] edema - inducing and hemorrhagic activities. The species includes five from family Elapidae; Hydrophis cyanocinctus, Enhydrina schistosa, Naja naja. Bungarus caeruleus and Microcephalophis gracilis gracilis whereas three from family Viperidae; Vipera russelli russelli, Eristochphis macmahoni and Echis carinatus. All venom tested moderate to high levels of lethal, hemolytic [both direct and indirect] and edema - inducing activities, except that venoms of snake species of family Elapidae, including the sea snake species, are characterized by low levels or absence of hemorrhagic activity. LD 50 values were found to be 0.39mg/kg 0.41 mg/kg 0.28 mg/kg. 0.30 mg/kg and 0.40 mg/kg for the species of family Elapidae respectively whereas 0.30 mg/kg, 0.26 mg/kg and 0.41 mg/kg for species of family Viperidae
Assuntos
Animais , Elapidae , Venenos de Serpentes/farmacologia , Disponibilidade BiológicaRESUMO
Protective effectiveness of two Ca2+ - antagonist drugs, verapamil and diltiazem were tested against nephrotoxic activity of sea - snake Microcephalphis gracilis gracilis venom in guinea pigs and albino rats. Administration of both lethal and sublethal does of Microcephalphis gracilis gracilis crude venom induced glomerulonephritis and tubular degeneration in kidneys of envenomated animals accompanied by increased tissue Ca2 + concentration. Administration of both verapamil and diltiazem in envenomated animals not only cause significant decrease in ca2 + concentration but also reduced necrosis and cellular degeneration in kidneys. It is thus suggested that cytotoxic compounds present in this marine vomom cause tissue and cellular necrosis by increasing Ca2+ influx within the cells which in turn stimulates Ca2 + -dependent processes resulting in both organ dysfunction and some - time fatality in few cases