高旦固醇血症患者血小板L-精氨酸/一氧化氮系统的改变

目的观察高胆固醇血症(HC)患者血小板L-精氨酸(L-Arg)/一氧化氮(NO)系统活性的变化。方法采用比色法检测21例HC患者和26名健康体检者血小板的NO水平，采用放射性核素(3H-L-精氨酸)标记法检测血小板一氧化氮合成酶(NOS)及L-Arg转运系统活性。结果HC患者血小板NO水平为(24.06±3.70)nmol/10

Changes in the activity ofplatelet L-arginine/nitric oxide pathway in hypercholesterolemia patients

OBJECTIVE: To investigate the changes of the platelet L-arginine (L-Arg)/nitric oxide (NO) pathway in hypercholesterolemia patients. METHODS: The platelet NO production in 21 hypercholesterolemia (HC) patients and 26 normal individuals was assayed by spectrum, the NOS activity and the transportation of L-Arg were determined by (3)H-labelled L-Arg. RESULTS: The NO production in hypercholesterolemic platelets [(24.06 +/- 3.70) nmol/10(8) platelets] was decreased significantly as compared with normal controls [(28.39 +/- 4.45) nmol/10(8) platelets] (P < 0.01), and so did the NOS activity [(1.46 +/- 0.47) pmol/10(8) platelets] vs (1.81 +/- 0.50) pmol/10(8) platelets]. The transportation of L-Arg by hypercholesterolemia platelets also decreased significantly than that by normal controls. The Vmax in the former [(46.84 +/- 3.39) pmol x (10(7) platelets)(-1) x min(-1)] was significantly lower than that in the latter [(53.89 +/- 3.45) pmol x (10(7) platelets)(-1) x min(-1)]. There was no difference between the two groups in K(d) (P > 0.05). CONCLUSIONS: The activity of the L-arg/NO pathway in hypercholesterolemia platelets is decreased significantly as compared with normal controls, implying that it is probably one of the reasons for the hyperactivity of hypercholesterolemia platelets.