title: Effect of suramin on myotoxicity of some crotalid snake venoms.
abstract: We investigated the protective effect of suramin, an enzyme inhibitor and an uncoupler of G protein from receptors, on the myotoxic activity in mice of different crotalid snake venoms (A.c. laticinctus, C.v. viridis, C.d. terrificus, B. jararacussu, B. moojeni, B. alternatus, B. jararaca, L. muta). Myotoxicity was evaluated in vivo by injecting im the venoms (0.5 or 1.0 mg/kg) dissolved in physiological saline solution (0.1 ml) and measuring plasma creatine kinase (CK) activity. Two experimental approaches were used in mice (N = 5 for each group). In protocol A, 1 mg of each venom was incubated with 1.0 mg suramin (15 min, 37 degrees C, in vitro), and then injected im into the mice at a dose of 1.0 mg/kg (in vivo). In protocol B, venoms, 1.0 mg/kg, were injected im 15 min prior to suramin (1.0 mg/kg, iv). Before and 2 h after the im injection blood was collected by orbital puncture. Plasma was separated and stored at 4 degrees C for determination of CK activity using a diagnostic kit from Sigma. Preincubation of some venoms (C.v. viridis, A.c. laticinctus, C.d. terrificus and B. jararacussu) with suramin reduced (37-76%) the increase in plasma CK, except for B. alternatus, B. jararaca or L. muta venoms. Injection of suramin after the venom partially protected (34-51%) against the myotoxicity of B. jararacussu, A.c. laticinctus and C.d. terrificus venom, and did not protect against C.v. viridis, L. muta, B. moojeni, B. alternatus or B. jararaca venoms. These results show that suramin has an antimyotoxic effect against some, but not all the North and South American crotalid snake venoms studied here.
authors.affiliation: Departamento de Farmacologia Básica e Clínica, Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil.
authors.forename: E Z
authors.initials: EZ
authors.lastname: Arruda
authors.forename: N M V
authors.initials: NM
authors.lastname: Silva
authors.forename: R A M
authors.initials: RA
authors.lastname: Moraes
authors.forename: P A
authors.initials: PA
authors.lastname: Melo
mesh_terms: D000818:Animals; D000997:Antivenins / Q000494:pharmacology*; D017837:Bothrops; D003402:Creatine Kinase / Q000378:metabolism; D003435:Crotalid Venoms / Q000037:antagonists & inhibitors* / Q000201:enzymology / Q000633:toxicity; D004353:Drug Evaluation, Preclinical; D051379:Mice; D009132:Muscles / Q000187:drug effects*; D013498:Suramin / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000997:Antivenins; D003435:Crotalid Venoms; D013498:Suramin; D003402:Creatine Kinase