硝苯地平对糖尿病患者血小板聚集功能和胞质钙的影响

Effects of nifedipine on the platelet aggregation and cytoplasmic free calcium in patients with diabetes mellitus

目的:探讨钙通道阻断剂硝苯地平对糖尿病患者血小板聚集(platelet aggregation,PAG)功能和血小板胞质游离钙(血小板[Ca2+]i)的作用。方法:用比浊法测定PAG,Fura-2荧光测钙技术测定血小板[Ca2+]i,观察硝苯地平对糖尿病患者PAG和血小板[Ca2+]i的影响。结果:①糖尿病患者PAG为(74.89±13.68)%,高于正常人的(61.58±13.49)%(P<0.05);②糖尿病患者的静息血小板[Ca2+]i值、钙释放、钙內流分别为(124.50±38.13)nmol/L、(497.09±95.07)nmol/L、(354.30±75.00)nmol/L,高于正常人的(106.16±24.22)nmol/L、(458.02±83.74)nmol/L、(320.42±85.22)nmol/L(P<0.05);③硝苯地平以浓度依赖的方式抑制血小板钙内流,IC50约为7.5μmol/L,7.5μmol/L硝苯地平对凝血酶激动的糖尿病患者血小板钙内流的抑制率为(17.85±11.93)%,对PAG的抑制率为(32.26±20.43)%。结论:糖尿病患者血小板聚集率、静息血小板[Ca2+]i及钙运动均高于正常人;钙通道阻断剂硝苯地平对糖尿病患者的血小板钙运动有遏制作用。

Objective：To explore the calcium channel blocker,nifedipine′s effects on the platelet aggregation and cytoplasmic free calcium（i） in patients with diabetes mellitus.Method：Maximum platelet aggregation（PAG） was measured through turbidimetric method by platelet aggregation meter,platelet i was measured through Fura-2 fluorescent marker.We observe the effect of nifedipine on the PAG and i in patients with diabetes mellitus.Result：The PAG in patients with diabetes was higher than that in normal control（（74.89±13.68）% vs.（61.58±13.49）%,P0.05）.The platelet resting i,calcium release and calcium influx were higher than those in normal control（（124.50±38.13）nmol/L,（497.09±95.07）nmol/L,（354.30±75.00）nmol/L vs.（106.16±24.22）nmol/L,（458.02±83.74）nmol/L,（320.42±85.22）nmol/L respectively,all P0.05））.Nifedipine could dose-dependently inhibit the platelet calcium influx and the 50% inhibiting concentration（IC50） was 7.5 μmol/L.7.5μmol/L nifedipine could inhibit the platelet calcium influx activated by thrombin by（17.85±11.93）% in patients with diabetes and PAG by（32.26±20.43）%.Conclusion：The PAG,platelet resting i and calcium activity in patients with diabetes is higher than those in normal control.Nifedipine,as a calcium channel blocker could inhibit the platelet calcium activity in patients with diabetes.