不同年龄自发性高血压大鼠血管平滑肌细胞Ca^（2＋）转运功能障碍及某些相关因素的变化

The Disturbance of Ca￣(2+)Transport ahd the Changes of Some Relative Factors in Arterial Smooth Muscle Cells from Spontaneously Hypertensive Rats with Different Age

应用不同年龄自发性高血压大鼠（ＳＨＲ）血管平滑肌原代与传代细胞（ＶＳＭＣ），观察Ｃａ２＋转运功能障碍及某些相关因素的变化。结果表明：（１）在血压未升高的ＶＳＭＣＣａ２＋内流已较同龄对照组ＷＫＹ大鼠明显增加，而Ｃａ２＋外流量较ＷＫＹ大鼠显著降低。表明ＳＨＲＶＳＭＣ膜Ｃａ２＋转运功能障碍在血压升高前就已发生，并随年龄及血压增高有加重趋势；（２）ＶＳＭＣｃＡＭＰ及钙调素（ＣａＭ）含量变化与细胞膜Ｃａ２＋转运功能障碍基本同步，提示二者异常与细胞膜Ｃａ２＋转运功能障碍有密切关系；（３）血压升高前ＳＨＲＶＳＭＣ内ＡＮＧⅡ含量与ＷＫＹ大鼠相比无明显差异，但１６周龄５ＨＲＶＳＭＣ内ＡＮＧⅡ含量明显高于其幼鼠（Ｐ＜０．００１），与血压呈正相关。提示ＶＳＭＣ内ＡＮＧⅡ在血压升高过程中可能具有一定作用。以上结果表明高血压时ＶＳＭＣ膜Ｃａ２＋转运功能障碍有明显遗传倾向，ＶＳＭＣ内ＣＡＭＰ、ＣａＭ及ＡＮＧⅡ含量异常与上述障碍密切相关。

The purpose of this study was to observe the abnormalities of calcium transport of cultured arterial smooth muscle cells(ASMC)in both prehypertensive and hypertensive SHR and their controI WKY rats.The changes in cAMP,ANG Ⅱand CaM contents in ASMC were also studied.The results indicated that the Ca2+ influx in ASMC of prehypertensive SHR was increased compared with that of the control,although the value of that in hypertensive SHR was higher significantly more than that of the prehypertensive rat,but there was no significant difference between them.On the other hand,the Ca2+efflux in ASMC of prehypertensive SHR was decreased compared with that of WKY rats,A more seriously decreased efflux value was found in hypertensive SHR.The cAMP and CaM content were higher than those in WKY rats,In addition,ANG Ⅱ content in ASMC had a direct bearing on blood pressure,showing a marked difference between prehypertensive and hypertensive SHR.The disturbance of transmembrane Ca2+transport in ASMC of hypertensive rats appears to be related to genetic defect and the changes of cAMP contents might play a role in membrane Ca2+transport in ASMC during the development of hypertension,Furthermore the level of arterial ANGⅡmay be related to the elevation of blood pressure in hypertension.