Scuka M
Pflugers Arch. 1977 Jul 19;369(3):239-44. doi: 10.1007/BF00582190.
The amplitude of the electrophoretically evoked end-plate potential increases with changing the pH of the bathing solution from 9.4 to 5.4 at room temperature. This change is not observed at lower temperature. The underlying current (e.p.c.I) is slightly decreasing at room temperature by lowering the pH. The relationship between the amplitude of the e.p.c.I and membrane potential is highly non-linear at pH 9.4, while it is quite linear at pH 5.4. The time course of the e.p.c.I is changed neither by different pH, nor by different membrane potential. The data suggest that during the e.p.c.I, the mediator (ACh), the receptor (R) and the mediator-receptor complex are in equilibrium: the amplitude of the e.p.c.I will thus depend on the affinity constant of the reversible reaction between ACh and R. It is concluded that by decreasing the pH, the affinity constant is decreased.
在室温下，将灌流溶液的pH从9.4变为5.4时，电泳诱发的终板电位幅度会增加。在较低温度下未观察到这种变化。在室温下，通过降低pH，基础电流（e.p.c.I）略有下降。在pH 9.4时，e.p.c.I幅度与膜电位之间的关系高度非线性，而在pH 5.4时则相当线性。e.p.c.I的时间进程既不受不同pH的影响，也不受不同膜电位的影响。数据表明，在e.p.c.I期间，介质（乙酰胆碱，ACh）、受体（R）和介质-受体复合物处于平衡状态：因此，e.p.c.I的幅度将取决于ACh与R之间可逆反应的亲和常数。得出的结论是，通过降低pH，亲和常数会降低。
