Modulation of Ca channels by the dihydropyridine Ca agonist Bay K 8644 in guinea-pig taenia coli smooth muscle cells was investigated using the patch clamp technique. 2. Single Ca channel activity was obtained from cell-attached patch recordings with the use of pipettes filled with 50 mM Ba. Bath application of the drug markedly increased the opening probability of Ca channels. 3. The effect was found to be due to an increase in the mean opening times of Ca channels. Due to this increase, the mean current reconstructed by averaging individual current trace responses was markedly increased in the presence of Bay K 8644.
摘要
运用膜片钳技术研究了二氢吡啶类钙激动剂Bay K 8644对豚鼠结肠带平滑肌细胞钙通道的调制作用。2. 使用装有50 mM钡的移液管，通过细胞贴附式膜片钳记录获得单个钙通道活性。药物浴应用显著增加了钙通道的开放概率。3. 发现该效应是由于钙通道平均开放时间增加所致。由于这种增加，在Bay K 8644存在的情况下，通过平均单个电流轨迹响应重建的平均电流显著增加。
