自发性高血压大鼠血小板胞浆游离钙和血小板功能的变化及其与心脏重塑的关系

目的　研究自发性高血压大鼠 (SHR)血小板胞浆游离钙和血小板功能的变化及其与心脏重塑的关系。方法　将 1 7只SHR分为 3组 :1月龄SHR组 (n =6 )、1 0月龄SHR组 (n =6 )和 1 8～ 2 0月龄SHR组 (n =5 )。每组均等数按鼠龄、体重及雌雄配对配予Wistar大鼠 (WKY)作对照。SHR和WKY的血小板胞浆游离钙、血小板聚集率、收缩压和左心室肥厚指数被测定。采用直线回归分析确定血小板胞浆游离钙、血小板聚集率与左心室肥厚指数的关系。结果　 (1 ) 1 0月龄SHR组和 1 8～ 2 0月龄SHR组血小板胞浆游离钙浓度和血小板聚集率均显著高于同龄WKY组和 1月龄SHR组 (P均 <0 .0 1 ) ,1 8～ 2 0月龄SHR组血小板胞浆游离钙浓度和血小板聚集率还显著高于 1 0月龄SHR组 (P <0 .0 1 )。 (2 ) 1 0月龄SHR组和 1 8～ 2 0月龄SHR组左心室肥厚指数均显著高于同龄WKY组和 1月龄SHR组 (P均 <0 .0 1 )。 (3)SHR血小板胞浆游离钙浓度和血小板聚集率与左心室肥厚指数呈显著正相关 (P均 <0 .0 1 )。结论　血小板内钙代谢异常和血小板功能改变可能在SHR心脏重塑中起重要作用

Alteration of platelet cytosolic free calcium and platelet aggregation and their relation with heart remodeling in spontaneously hypertensive rats

Objective To study the alteration of platelet cytosolic free calcium and platelet aggregation and their relation with heart remodeling in spontaneously hypertensive rats(SHR). Methods Platelet cytosolic free calcium concentration was measured using fluorescent probe Fura 2 AM and the degree of platelet aggregation was determined according to the turbidimetric method of Born. In addition, left ventricular hypertrophic index was investigated, and the relationship among platelet cytosolic free calcium concentration and the degree of platelet aggregation and left ventricular hypertrophic index were studied statistically. Results (1) The platelet cytosolic free calcium concentration and the degree of platelet aggregation were higher in 10 month old SHR group and 18 20 month old SHR group than those in age matched WKY group and 1 month old SHR group(all P values less than 0.01), and the platelet cytosolic free calcium concentration and the degree of platelet aggregation were higher in 18 20 month old SHR group than that in 10 month old SHR group yet(all P values less than 0.01). (2)The left ventricular hypertrophic index was notably increased in 10 month old SHR group and 18 20 month old SHR group compared with age matched WKY group and 1 month old SHR group (all P values less than 0.01). (3) The platelet cytosolic free calcium concentration and the degree of platelet aggregation were positively related to the left ventricular hypertrophic index(all P values less than 0.01).Conclusion The abnormality of platelet cytosolic calcium metabolism and the changes of platelet function may play an important role in heart remodeling of SHR.