自发性高血压模型大鼠(SHR)与SD大鼠大脑中动脉的应力松弛特性

研究5月龄SD雄性大鼠和5月龄SHR雄性大鼠大脑中动脉的应力松弛特性.为了解高血压的发病机制提供应力松弛特性参数.对5月龄正常SD雄性大鼠大脑中动脉和5月龄自发性高血压模型大鼠(SHR)大脑中动脉各10个试样在日本岛津电子万能试验机上对SD大鼠和SHR大鼠大脑中动脉进行应力松弛实验,在(36.5±0.5)％的温度场下以0.05％/s的应变增加速度对试样施加应变,设定时间为7200s.采集100个数据,采用归一化分析的方法计算两组试样的归一化应力松弛函数方程.两组试样应力松弛曲线是以指数关系变化的,SD大鼠组大脑中动脉试样7200 s应力下降大于SHR组大脑中动脉试样,差异显著(P＜0.05).正常SD大鼠中动脉和SHR大鼠大脑中动脉具有不同的应力松弛特性,SHR大鼠中动脉应力松弛特性发生改变.

Middle Cerebral Artery Stress Relaxation Properties of the Spontaneously Hypertensive Rat Models(SHR) and the SD Rats

To observe the stress relaxation properties of 5 month-old SD male rats and 5 month-old SHR male rat’s middle cerebral arteries to find out the pathogenesis of hypertension and provide stress relaxation mechanical parameters. Toke 10 middle cerebral arteries’ samples of 5 months old normal SD male rats,and the 5 months old spontaneously hypertensive model rats(SHR),respectively,then installed them in electronic testing machine to do the stress relaxation test,simulated the human bady temperature at(36.5±0.5)℃.The samples were done forcibly by 0.05%/s strain increases velocity,the time was set on 7 200 s,100 data were collected.The stress relaxation equations of the two groups’ samples were calculated by using normalized analysis method. The stress relaxation curve of the two groups’ samples was changed by exponential relationship.The stress reduction of the middle cerebral arteries’ samples of the SD rats at 7 200 s was greater than that of SHR rats’,there was significant difference(P<0.05).The middle cerebral arteries of the normal SD rats and SHR rats have different stress relaxation properties.The stress relaxation of middle cerebral arteries of the SHR rats have been changed.