[Alpha 2 megaloglobulin inhibits the activation of rabbit platelet by Chinese Agkistrodon acutus venom].

An in vitro study of alpha 2-mengaloglobulin (alpha 2MG) in the inhibition of the activation of washed rabbit platelet by Chinese Agkistrodon acutus venom (CAAV) was reported. Results showed that CAAV induced aggregation rate of washed rabbit platelet was positively related to the CAAV concentration, and the maximal aggregation rate was 43.8 +/- 9.9% at the concentration of 100 micrograms/ml. Meanwhile the release of serotonin (5-HT) and platelet factor 4(PF4) from the platelet reached maximum at the CAAV concentrations of 0.81 +/- 0.07 microgram/ml and 39.08 +/- 2.78%, respectively. Platelet aggregation and the release of 5-HT and PF4 induced by CAAV could be inhibited by the addition of 0.25% alpha 2 MG into the platelets both 1 minute before and 1 minute after the addition of CAAV. When alpha 2 MG was added to the platelets 1 minute prior to the addition of CAAV, the platelet aggregation and the ultrastructural changes which could be induced by CAAV were not observed, and the morphology of the rabbit platelets was the same as that of the normal counterparts.