摘要
比较了冠心病组和对照组血小板5-羟色胺2A受体密度，以及次极量平板运动试验对两组血小板5-羟色胺2A受体的影响，结合血浆5-羟色胺水平变化，以探讨5-羟色胺2A受体在心血管疾病血小板高反应中的作用。结果表明：血小板5-羟色胺2A受体与3H-酮色林特异结合具有饱和特性。安静状态下，冠心病组血小板5-羟色胺2A受体密度及血浆5-羟色胺水平均明显高于对照组，运动试验使受体密度及最大结合容量，血浆5-羟色胺水平进一步增加。对照组运动试验前后血小板5-羟色胺2A受体密度及最大结合容量，以及血浆5-羟色胺水平未见明显变化。提示血小板5-羟色胺2A受体密度增加与冠心病血小板高反应性有关，运动试验使冠心病组血小板5-羟色胺2A受体进一步增加，从而参与运动诱发的急性心肌缺血。
It is known both 5-HT2A receptors of platelet and vascular smooth muscle regulate vas-cular constriction and platelet aggregation to 5-HT challenge- And that 5-HT-induced hyp-perreactivity of vascular smooth muscle and platelet were noted in patients with coronaryartery disease (CAD). In order to investigate the mechanism of platelet hyperreactivity incardiovascular disease. Platelet 5-HT2A receptor were measured by specific binding of 3H-ke-tanserin in patients with CAD(CAD group) and patients with chest pain but without CAD aswell as healthy subjects (control group) before and after submaximal treadmill exercise. Atthe same time the levels of plasma 5-HT were also measured. The results showed: (1 ) Inthe resting state, 3H-ketanserin exhibited saturable binding with Bmax of 7l. 1 f 1O. 1 fmol/mg protein, Kd1. 350. 20 nmol/L in control group (n=8) and with Bmax of 102. 1 22. 2fmol/mg protein, Kd 2. 44l 0. 66 nmol/L in CAD group (n = 1O). Between two groups hadno significant difference (P>0. 05). And the specific binding of 2' o nmol/L 3H-ketanserinand the level of plasma 5-HT in CAD group were higher than those in control group (P<0.05). (2) After exercise all of the specific binding of 2. 0 nmol/L 3H-ketanserin, Bmax ofreceptor binding and the level of plasma 5-HT were significantly increased in CAD group butnot in control group. The above results suggested that the up-regulation of platelet 5-HT2Areceptor was involved in the platelet hyperreactivity in CAD. The submaximal treadmi1l ex-ercise had no significant effect on platelet function in control group, but it could lead toplatelet 5-HT2A receptor increment and platelet activation in CAD group. Therefore, thesechanges of platelet might play a role in the acute myocardial ischemia induced by exercise.
出处
《中国医学科学院学报》
CAS
CSCD
北大核心
1997年第5期336-341,共6页
Acta Academiae Medicinae Sinicae
基金
国家自然科学基金!39470302
关键词
5-羟色胺2A受体
冠心病
运动试验
血小板
5-HT_(2A) receptor
3H-ketanserin
coronary artery disease
exercise test
