自发性高血压大鼠动脉平滑肌细胞内肌醇磷脂代谢的改变

ALTERATION OF INOSITOL PHOSPHATE METABOLISM IN AORTIC SMOOTH MUSCLE CELLS FROM SPONTANEOUSLY HYPERTENSIVE RAT

本研究观察了在基础状态下和G蛋白激活后，自发性高血压大鼠动脉平滑肌细胞内肌醇磷脂代谢的改变。结果显示：在基础状态下自发性高血压大鼠动脉平滑肌细胞内三磷酸肌醇的含量基本正常；GTPγS激活G蛋白后，动脉平滑肌细胞三磷酸肌醇的增加呈剂量和时间依赖性；G蛋白的持续激活使自发性高血压大鼠的三磷酸肌醇的增量显著大于Wistar－Kyoto对照组大鼠。上述结果提示，自发性高血压大鼠动脉平滑肌细胞内G蛋白-肌醇磷脂途径对外源性刺激的敏感性过高，这可能与该途径一些成分的数目、结构或功能存在着某些变异有关。

The changes of inositol phosphates in quiescent alld GTPγS activated vascular.smooth muscle cells (VSMC) derived ftam aorta of spontaneously hypertensive rat(SHR) were examined. The inositol phosphate assay revealed that there was no difference in the inositol-1, 4, 5-triphosphate (InsP3) level between the quiescent VSMCs ofSHR and that of normotensive Wistar-Kyoto ratd (WKY). G-protein activator GTPγScaused a dose- and time-dependent increase in the InsP3 level in VSMCs. Activated Gproteins increased significantly the InsP3 level in VSMCs of SHR. In conclusion, thehighly sensitive reactivity to GTPγS in the generation of InsP3 in VSMCs from SHRmay be related to the possible abnomality of the number, substructure or function ofsome components in G proteins, phosphoinositide turnover.