Abstract: AIM: To explore the effect and mechanism of platelet inhibitor from Agkistrodon halys venom (AHV-PI) on artery thrombosis in rabbits. METHODS: Twenty-four New Zealand rabbits were randomly divided into normal control, artery thrombosis model, positive control (sodium ozagrel at dose of 5 mg/kg) and AHV-PI (0.1 mg/kg) experiment groups (n=6 for each). The model of rabbits carotid artery thrombosis was induced by infiltering 70% FeCl₃. Thrombelastogram was obtained by thromboelastography instrument. The experiment of platelet aggregation was determined by the turbidimetric method. The content of GMP-140 and TXB₂ in plasma were determined by ELISA. The structural changes of the artery thrombosis and platelet were observed under microscope and transmission electron microscope respectively. RESULTS: Compared with model group, R and K were significantly prolonged in AHV-PI experiment group. The alpha angle, MA, CI and the indices of platelet aggregation were decreased (P<0.01 and P<0.05). The levels of GMP-140 and TXB₂ in plasma were decreased (P<0.01). Artery thrombosis histological observation showed that thrombosis in AHV-PI experiment group were not found. Platelet electron microscope showed that the platelet morphology and ultrastructure approach normal control group. AHV-PI can inhibit producing pseudopods process and increase in the number of theαgranules associated with enhanced intensities of their electron densities compared with model group. CONCLUSION: AHV-PI can inhibit platelet aggregation and provent the information of artery thrombosis. The mechanism may be attributed to protecting platelet ultrastructure and reducing the release of platelet lipid metabolism and particulate contents.

Key words: Agkistrodon halys venom, Platelet inhibitor, Artery thrombosis, Platelet