Effects Of Tongxinluo Capsule On Activity Of Platelet Endothelial NitricOxide Synthase In Patients With ACS(Acute Coronary Syndrome)

It is well-known that the adhesion, activation and aggregation of platelets played an important role in the pathogenesis of acute coronary syndrome (ACS). The key point of platelet function in healthy adult is the relative balance between the aggregation and anti-aggregation of platelet: the factors promoting the aggregation of platelets such as ADP, 5-hydroxytryptamine, collagen, thromboxane A₂,etc; on the other hand, Nitric Oxide(NO) is the dominate factor preventing the aggregation of platelets. The synthesis of NO mainly through nitrogen atom and oxygen molecule of L-arginine by the catalysis of endothelial Nitric-Oxide Synthase, this biochemical process is called L-arg/NO pathway. It was found that the L-arg/NO pathway also existing on platelet. According to basic research, Tongxinluo capsule has some effecs in reducing blood cholesterols,anticoagulant and inhibiting adhesion and aggregation of platelets. The drug has been widely used for a variety of cardiovascular diseases (including angina pectoris, myocardial infarction, atherosclerosis, etc). However, the mechanism of Tongxinluo capsule about the anti-platelet aggregation was rarely studied. The purpose of this clinical study is whether the anti-platelet aggregation effect of Tongxinluo Capsule being associated with the L-arg/NO systems of platelet.Objective: To observe whether the anti-platelet aggregation action of Tongxinluo capsule in patients with ACS is associated with the L-arg/NO pathway of platelet.Methods: Twenty patients with ACS were recruited from the Department of Cardiology, Nanjing Gulou hospital. They were randomly divided into standard treatment group (intervention, anti-coagulant, anti-platelet, lipid-lowering, coronary artery dilating medicine) and Tongxinluo treatment group (intervention, anti-coagulant, anti-platelet, lipid-lowering, coronary artery dilating medicine and Tongxinluo capsule 4^# tid). Blood samples were drawn before and after one month therapy. The platelets were isolated by gel-filtration chromatography. eNOS activity was mensured as formation of ³H-L-citrulline from ³H-L-arginine.Results: After one month, the platelet eNOS activity was activated obviously in both groups (P=0.004/P=0.002); There was no significant difference of platelet eNOS activity in the beginning between the two groups (P=0. 875) . After taking Tongxinluo capsule for one month, the platelet eNOS activity was significantly higher than standard therapy group (P=0. 001). In Tongxinluo group, there were no significant difference of ALT,BUN,Cr and UA(P=0. 844,0.646,0. 393,0. 563). Tongxinluo capsule was safe and effective in clinic use without any adverse effects.Conclution: In patients with ACS, concomitant use of Tongxinluo capsule has the effect of anti-platelet aggregation. The mechanism was supposed to be increasing the platelet eNOS activity through activating L-arg/NO pathway on platelets. It has provided some theoretical basis for the treatment of cardiovascular and cerebrovascular thrombotic diseases with Tongxinluo capsule.