Graham D, Simpson H D, Dominiczak A F, Caslake M, Davies D L, Kenyon C J
Department of Medicine and Therapeutics, Western Infirmary, Glasgow, UK.
J Hum Hypertens. 1995 Sep;9(9):753-8.
The influence of high density lipoproteins (HDL) on platelet function were examined in vivo and in vitro. Intraplatelet, ionised calcium concentrations ([Ca2+]i) were measured using the fluorescent dye Quin-2. In vitro, platelet responses to AVP were measured in the presence or absence of HDL. Pre-treating platelets from normal volunteers with HDL in vitro lowered the [Ca2+]i response to AVP but did not significantly affect basal values. In vivo, plasma lipoprotein profiles in normotensive (13 men, 17 women) and hypertensive (13 men, 11 women) subjects were compared with basal and AVP-stimulated platelet [Ca2+]i values. Plasma [HDL] were not related to basal or stimulated [Ca2+]i. Plasma cholesterol concentrations were higher in the hypertensive patients largely because low density lipoprotein [LDL] were raised in male hypertensive patients. Plasma [LDL] and total plasma cholesterol correlated negatively with basal [Ca2+]i (but not with AVP-stimulated values) only in this subgroup. In hypertensive patients, AVP-stimulated [Ca2+]i (but not basal values) were lower than normotensive controls. From in vitro studies, it may be concluded that the anti-atherogenic properties of HDL might be mediated by inhibition of platelet reactivity. However, ex vivo a negative influence of LDL on basal (not stimulated) [Ca2+]i appears to be paramount.
在体内和体外研究了高密度脂蛋白（HDL）对血小板功能的影响。使用荧光染料喹啉-2测量血小板内的游离钙浓度（[Ca2+]i）。在体外，在有或没有HDL的情况下测量血小板对血管加压素（AVP）的反应。体外使用HDL预处理正常志愿者的血小板可降低对AVP的[Ca2+]i反应，但对基础值无显著影响。在体内，将血压正常者（13名男性，17名女性）和高血压患者（13名男性，11名女性）的血浆脂蛋白谱与基础和AVP刺激的血小板[Ca2+]i值进行比较。血浆[HDL]与基础或刺激后的[Ca2+]i无关。高血压患者的血浆胆固醇浓度较高，主要是因为男性高血压患者的低密度脂蛋白（LDL）升高。仅在该亚组中，血浆[LDL]和总血浆胆固醇与基础[Ca2+]i呈负相关（但与AVP刺激值无关）。在高血压患者中，AVP刺激的[Ca2+]i（而非基础值）低于血压正常的对照组。从体外研究可以得出结论，HDL的抗动脉粥样硬化特性可能是通过抑制血小板反应性来介导的。然而，在体外，LDL对基础（而非刺激后）[Ca2+]i的负面影响似乎最为重要。
