Aim To study the effect of PLC on rabbit platelet cAMP , and then to explore the mechanism of PLC anti-aggregation to
platelet. Me thod Rabbit platelets removed of red cells were treated with PSS, ASA an d different dose of PLC respectively and induced by ADP respectively. cAMP was extracted by trichloroacetic acid.The
concentration of cAMP of differently trea ted platelets was determined by RIA (radioimmunoassay). Result When rabbit platelets were treated with PSS, the concentration of cAMP at static state was 20.16±0.91 pmol/109 platelets; when the platelets were treated w ith PSS、ASA 668 μ mol·L -1,5,10,15,20 and 25 U PLC·ml -1, the conc entration of cAMP of determined at activated state induced by ADP was 13.85±1 .14, 16.27±0.36,18.74±0.55, 19.80±0.52, 20.49±0.43, 22.55±0.61 and 24.24±0.85(pmol/109 platelets) respectively. Compared with PSS, enha nced rates ( % ) of ASA 668 μmol·L -1, 5, 10, 15, 20, 25 U PLC·ml -1 to the concentration of cAMP were 17.47, 35.31, 42.96, 47.94, 62.82, 75 .02 respectively. Conclusion PLC has significant effects on the concentration of cAMP of rabbit platelets(P<0.01), and increases cAMP dos e-dependantly(P<0.01). All these indicate PLC can enhance the concentrati on of cAMP. This may be one of the important reason why PLC can inhibit platele t aggregation.