Kanno Y, Muneoka Y, Yamami T
Jpn J Physiol. 1977;27(6):771-83. doi: 10.2170/jjphysiol.27.771.
The membrane potential of mucous epithelial cells of isolated newt stomach was -23 mV on the average at 7 degrees C. The potential decreased when the temperature was lowered further, the normal external solution was replaced with K+-free solution, or ouabain or DNP was applied. The decreased membrane potential level of the cells in K+-free solution was not changed any more by adding ouabain to the solution. The membrane potential increased transiently beyond the control level when the stomach was returned to the normal solution after being exposed to isotonic NaCl solution with EGTA. The transient potential increase was blocked by ouabain. These results suggest that, even at such a low temperature as 7 degrees C, the active ion transport mechanism(s) of mucous epithelial cells in the newt stomach is still capable of functioning to some extent.
在7摄氏度时，离体蝾螈胃黏液上皮细胞的膜电位平均为-23毫伏。当温度进一步降低、正常的细胞外溶液被无钾溶液替代、或者应用哇巴因或二硝基酚（DNP）时，膜电位下降。在无钾溶液中，细胞的膜电位降低水平不会因向溶液中添加哇巴因而进一步改变。当胃在暴露于含乙二醇双四乙酸（EGTA）的等渗氯化钠溶液后再回到正常溶液时，膜电位会短暂升高超过对照水平。这种短暂的电位升高被哇巴因阻断。这些结果表明，即使在7摄氏度这样的低温下，蝾螈胃黏液上皮细胞的主动离子转运机制仍能在一定程度上发挥作用。
