Objective This paper reports a potent platelet aggregation inhibitor which was an acidic PLA 2 purified from Ophiophagus
hannah venom Methods Acidic PLA 2 was obtained from Guangdong
Ophiophagus hannah venom by column chromatography and rechromatography on CM Sephadex C 25, Sephadex G 75, DEAE Sephadex A 25 The purity was tested by polyacrylamid gel
electrophoresis ,gel isoelectric focusing electrophoresis and SDS electrophoresis; Molecular weight was determined by SDS PAGE The activity measurement of PLA 2 was carried out by automatic titration;The experiment of platelet aggregation was by the turbidimetric method Results Acidic PLA 2 was purified as a monomer, pI 3 8, MW 14KD, PLA 2 enzyme activity 20 μmol·mg 1 ·min 1 ,LD 50 (ip)7 53±1 29mg kg 1 Inhibition of rabbit platelet aggregation induced by ADP,arachidonic acid(AA),thrombin(thr) was dose dependent Conclusion Acidic PLA 2 from Ophiophagus hannah venom could inhibit platelet aggregation induced by ADP,AA,thr