title: Gila monster and mexican beaded lizard venoms enhance guanylate cyclase activity.
abstract: Gila monster (Heloderma suspectum) and Mexican beaded lizard (Heloderma horridum) venoms enhanced rat liver, lung, heart, kidney, cerebellar and ileal guanylate cyclase [E.C.4.6.1.2] activity two- to threefold at their 1 microgram/ml concentrations. Dose response relationships revealed that the ED50 for stimulation of guanylate cyclase was 10 ng/ml while a concentration of 1 microgram/ml was necessary for the maximal activation with both venoms. Varying the concentration of the guanylate cyclase co-factor maganese had no effect on these lizard venoms' enhancement of guanylate cyclase activity. Since bee venom and the alpha-toxins of poisonous snakes krait and cobra also enhance the soluble form of guanylate cyclase, it appears that at the cellular level the mechanism of action of venoms and animal toxins may include a common process that involves enhancement of guanylate cyclase activity.
mesh_terms: D000818:Animals; D002712:Chlorides; D006162:Guanylate Cyclase / Q000378:metabolism*; D008099:Liver / Q000201:enzymology; D008116:Lizards / Q000502:physiology*; D008297:Male; D008345:Manganese / Q000378:metabolism / Q000494:pharmacology; D017895:Manganese Compounds; D051381:Rats; D011919:Rats, Inbred Strains; D014688:Venoms / Q000494:pharmacology*
chemical_list: D002712:Chlorides; D017895:Manganese Compounds; D014688:Venoms; D008345:Manganese; D006162:Guanylate Cyclase; C025340:manganese chloride