Berger W, Grygorcyk R, Schwarz W
Pflugers Arch. 1984 Sep;402(1):18-23. doi: 10.1007/BF00584826.
Attempts have been made to apply the patch-clamp technique to enzymatically dispersed smooth muscle cells of frog and toad stomach. The rate of successful gigaseal formation has been extremely low, but better results can be obtained when patches are taken from membrane evaginations which develop on single cells after mechanical agitation and incubation in Ca2+-containing solutions at 25 degrees C. Also ball-shaped single cells formed by the confluence of membrane evaginations were found to be equally useful for patch-clamp studies. Giga-seal formation was obtained in more than 80% of all attempts. Electron micrographs indicate that the myofilaments in membrane evaginations and in ball-shaped cells are separated from the cell membrane. Channel activity in membrane patches of such "myoballs" or evaginations is similar to the channel activity as found in intact cells. Two types of K+ channels (100 and 200 pS) have been observed that can be blocked by tetraethylammonium. Channels with the conductance of 200 pS are activated by intracellular Ca2+. The formation of evaginations has also been observed in other cells and may help to apply the patch-clamp technique to cells contaminated with surface coats.
人们已尝试将膜片钳技术应用于青蛙和蟾蜍胃的酶分散平滑肌细胞。形成千兆封接的成功率极低，但当从单细胞在25℃含Ca2+溶液中机械搅拌和孵育后形成的膜外翻处获取膜片时，能得到更好的结果。由膜外翻融合形成的球形单细胞也被发现同样适用于膜片钳研究。在所有尝试中，超过80%成功形成了千兆封接。电子显微镜照片表明，膜外翻和球形细胞中的肌丝与细胞膜分离。这种“肌球”或外翻膜片的通道活性与完整细胞中的通道活性相似。已观察到两种类型的钾通道（100和200 pS），它们可被四乙铵阻断。电导为200 pS的通道由细胞内Ca2+激活。在其他细胞中也观察到了外翻的形成，这可能有助于将膜片钳技术应用于被表面被膜污染的细胞。
