Effect of the venom of the snake Cerastes cerastes (African desert horned viper) on the response of the rat vas deferens to field stimulation.
Cerastes cerastes venom in low concentrations (0.8-2.5 micrograms/ml) inhibited the response of the rat vas deferens to field stimulation, while higher concentrations (4-8 micrograms/ml) causes a contracture that was reversed by washing and transiently blocked by phentolamine. The effect of the venom and guanethidine (10(-7) M) was reversed by tyramine (4.6 x 10(-8) M) but unaffected by hexamethonium (1.4 x 10(-7) M). When the response to field stimulation was inhibited by the venom the response to norepinephrine was either potentiated or unchanged.
D000818:Animals; D004558:Electric Stimulation; D006145:Guanethidine / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D010646:Phentolamine / Q000494:pharmacology; D051381:Rats; D012911:Snakes; D009435:Synaptic Transmission / Q000187:drug effects*; D014439:Tyramine / Q000494:pharmacology; D014649:Vas Deferens / Q000187:drug effects*; D014757:Viper Venoms / Q000633:toxicity*
D014757:Viper Venoms; D014439:Tyramine; D010646:Phentolamine; D006145:Guanethidine