Release of sarcoplasmic enzymes from skeletal muscle by Bothrops jararacussu venom: antagonism by heparin and by the serum of South American marsupials.

The venom of B. jararacussu induced a time- and dose-dependent (2-100 micrograms/ml) increase in the rate of release of sarcoplasmic enzymes (CK and LDH) from isolated rat and frog muscles. This effect, which we attribute to sarcolemmal damage by the venom, persisted in a Ca2+-free media, suggesting that phospholipase A activity was not required. The venom-induced enzyme release from the isolated muscles was reversibly inhibited by the sera (1-10 microliters/ml) of the marsupials Didelphis marsupialis aurita and Philander opossum, by an acidic glycoprotein fraction isolated from the opossum serum (50 micrograms/ml), and by heparin (50 micrograms/ml). Incubation of the B. jararacussu venom with opossum sera or heparin prevented the increase in plasma CK level observed in mice in which the snake venom (2.5-5.0 micrograms/g) was injected i.m. It is suggested that formation of acid-base complexes between basic myotoxins of B. jararacussu venom and either acidic components in the marsupial sera or the polyanionic heparin could account for the inhibition of the in vitro and in vivo effects of the venom on the release of sarcoplasmic enzymes from skeletal muscles.