Thomas R C
Physiology Department, School of Medical Sciences, Bristol University, UK.
Ciba Found Symp. 1988;139:168-83. doi: 10.1002/9780470513699.ch10.
Surface pH was recorded on voltage-clamped snail neurons with Hinke-type glass microelectrodes. During stepwise depolarization from -50 mV to +40 mV the surface pH usually increased at first and then fell rapidly during each 7.5 sec voltage step. The pH changes appeared to be due to proton passage through voltage-sensitive channels. The pH changes were inhibited by cadmium and zinc, and were not as sensitive to external pH as to internal pH. Changes in internal pH lagged behind surface pH. Changes in external calcium had little effect on the surface pH increases seen with small depolarizations. These results confirm earlier conclusions that depolarization opens proton-permeable channels.
使用欣克型玻璃微电极在电压钳制的蜗牛神经元上记录表面pH值。在从 -50 mV逐步去极化到 +40 mV的过程中，表面pH值通常先升高，然后在每个7.5秒的电压阶跃期间迅速下降。pH值变化似乎是由于质子通过电压敏感通道所致。pH值变化受到镉和锌的抑制，并且对外部pH值的敏感性不如对内部pH值的敏感性。内部pH值的变化滞后于表面pH值。外部钙的变化对小去极化时观察到的表面pH值升高影响很小。这些结果证实了早期的结论，即去极化会打开质子可渗透通道。
