IMMUNOGLOBULIN-G AND F(AB')(2) POLYVALENT ANTIVENOMS DO NOT DIFFER INTHEIR ABILITY TO NEUTRALIZE HEMORRHAGE, EDEMA AND MYONECROSIS INDUCEDBY BOTHROPS-ASPER (TERCIOPELO) SNAKE-VENOM

The ability of whole immunoglobulin G (IgG) and F(ab')(2) polyvalent ( Crotalinae) antivenoms to neutralize the hemorrhagic, edema-forming an d myotoxic activities of Bothrops asper venom was studied. Both antive noms were adjusted to the same neutralizing potency against lethal and hemorrhagic activities in experiments where venom and antivenoms were incubated before injection. Thus, in these experimental conditions, d ifferences in the neutralizing ability in experiments involving indepe ndent injection of venom and antivenoms would depend mainly on the dif ferent pharmacokinetic profiles of whole IgG and F(ab')(2) antivenoms. Experiments involving local injection of venom followed by intravenou s administration of antivenom at either 0, 15 or 30 min after envenoma tion did not reveal any significant difference between whole IgG and F (ab')(2) products concerning neutralization of hemorrhage, edema and m yonecrosis induced by B. asper venom. The three effects were neutraliz ed by antivenoms only to a partial extent and neutralization decreased as the time-lapse between envenomation and antivenom administration i ncreased. Moreover, with the exception of one time-interval, no signif icant differences in the neutralization of hemorrhage were observed wh en antivenom was administered by the intramuscular or intraperitoneal route. The results do not support the assumption that F(ab')(2) antive nom is more effective than whole IgG antivenom in the neutralization o f local hemorrhage, edema and myonecrosis induced by B. asper venom in mice. (C) 1997 Elsevier Science Ltd.