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应用倒置显微镜闭路电视系统及Ｃａ（２＋）敏感的荧光指示剂Ｆｕｒａ－２／ＡＭ的方法，记录培养心肌细胞的自发性收缩及［Ｃａ（２＋）］ｉ，瞬间变化，结果发现：应用血管紧张素Ⅱ（ＡｎｇⅡ，１０－１０００ｎｍ０１／Ｌ）５ｍｉｎ后，心肌细胞收缩频率增加，分别增加了５５％，８３％及１０７％，但同样浓度的ＡｎｇⅡ引起细胞边缘运动的速度减少。ＡｎｇⅡ１０，１００ｎｍｌ／Ｌ引起［Ｃａ（２＋）］ｉ瞬间变化最大值的明显增加，分别增加了１６％和３７％。但对［Ｃａ］ｉ（２＋）瞬间变化的基线水平没有明显的影响。结果提示：１．ＡｎｇⅡ增加心肌细胞搏动频率与增加细胞内游离Ｃａ（２＋）有关；２．ＡｎｇⅡ对心肌细胞收缩及［Ｃａ（２＋）］ｉ瞬间变化的作用可能关系到其影响Ｃａ（２＋）内流或细胞内Ｃａ（２＋）释放的机制，３．ＡｎｇⅡ减少心肌细胞收缩速度的机制值得进一步研究。
The spontaneous contractions of cultured cardiomyocytes and the transient changes of [Ca (2 +)] i were recorded by inverted microscope closed circuit television system and Fura-2 / AM fluorescent probe that is sensitive to Ca 2+. The results showed that: Cardiac muscle contraction frequency increased by 55%, 83% and 107% respectively after AngⅡ (10-1000nm01 / L) for 5min. However, the same concentration of AngⅡ caused a decrease in the rate of cell edge movement. AngII10, 100nml / L caused a significant increase in the maximum value of [Ca (2 +)] i transient increase by 16% and 37% respectively. But had no significant effect on the baseline level of [Ca] i (2+) transient changes. The results suggest: 1. Ang Ⅱ increases the frequency of myocardial cell pulsation and increased intracellular free Ca (2); 2. The effect of AngⅡ on cardiomyocyte contraction and transient changes of [Ca (2 +)] i may be related to its mechanism of affecting Ca (2+) influx or intracellular Ca (2+) release.3. The mechanism by which AngⅡ reduces the contractile rate of cardiomyocytes deserves further study.