Loirand G, Pacaud P, Mironneau C, Mironneau J
Pflugers Arch. 1986 Nov;407(5):566-8. doi: 10.1007/BF00657519.
Smooth muscle cells were isolated from rat portal vein and studied during short-term primary culture using the whole-cell patch-clamp technique. Two distinct types of Ca channel could be separated by studying the inward currents in Ba solutions. The rapidly inactivating current was present when cells were held at very negative potentials (-80 mV). This current was prominent for relatively small depolarizations and was insensitive to nifedipine. A slowly inactivating current, corresponding to the slow Ca current previously reported in smooth muscles, was observed at less negative holding potentials (-50 mV), was prominent for positive depolarizations and was blocked by low concentrations of nifedipine. Both currents were unaffected by tetrodotoxin and both were blocked by Co.
从大鼠门静脉分离出平滑肌细胞，并使用全细胞膜片钳技术在短期原代培养过程中进行研究。通过研究钡溶液中的内向电流，可以分离出两种不同类型的钙通道。当细胞保持在非常负的电位（-80 mV）时，存在快速失活电流。这种电流在相对较小的去极化时很突出，并且对硝苯地平不敏感。在较低的负性钳制电位（-50 mV）下观察到一种缓慢失活电流，对应于先前在平滑肌中报道的慢钙电流，在正性去极化时很突出，并被低浓度的硝苯地平阻断。两种电流均不受河豚毒素影响，且均被钴阻断。
