摘要
以心肌细胞动作电位（AP）参数的变化为指标，以α1—肾上腺素受体（α1－AR）亚型激动剂和选择性阻断剂为工具药，研究α1－AR亚型对大鼠心室肌细胞AP的影响，结果表明，α1－AR激动剂苯肾上腺素（PE）10-7mol／L使动作电位时程（APD）显著延长，PE10-5mol／L使动作电位时程50（APD50）比对照值延长59．9％，WB4101和5—UP在10-9mol／L浓度能有效地阻断PE10-7mol／L的作用。5－UP浓度升至10-7mol／L时，完全阻断PE10-5mol／L的效应，对α1B有强烷化作用的氯乙基可乐定（CEC），在10－5mol／L时．尽管APD50延长的程度减少但仍比对照经显著。由此提示大鼠心室肌细胞α1A亚型的激活是引发APD延长的主要亚型。
The present study was to investigate the effect of al -Adrenoceptor subtype on the action potential (AP) in rat ventricular muscle cells. The experiment was performcd by observing parameters of ventricular mucle cell AP and by using some agonists and selec tive subtype antagonists of α1 -adrenoceptor. The results showed that changes in action po tential duration (APD) were an effective indication of activation and blockade of α1 -adreno ceptor in rat ventricular muscle cells- α1 -agonist, phenyphrine (PE), could cause significant prolongation of APD at the dose of 10~7 mol/L and produce maximal prolongation of APD at 10-5 mol/L (59. 9 % as compared with that of control). 5- UP and WB4101 at the dose of 10-8 mol/L could block the response of 10-7 mol/L PE. When the concentration of 5-UP or WB4101 was increased to 10-7 mol/L, they could completely block the effect of APD prolon gation at 10-5 mol/L PE. These results indicated that α1A was the principal subtype responsi ble for prolongating APD when α1 -adrenoceptor was activated.
出处
《汕头大学医学院学报》
1997年第1期5-9,共5页
Journal of Shantou University Medical College
