Acetylcholine receptor inactivation in Torpedo californica electroplax membrane vesicles. Detection of two processes in the millisecond and second time regions.
Acetylcholine receptor inactivation in Torpedo californica electroplax membrane vesicles. Detection of two processes in the millisecond and second time regions.
复制标题
加州鱼雷 electroplax 膜囊泡中乙酰胆碱受体失活。
DOI：
10.1016/s0006-291x(81)80066-6
复制
发表时间：
1981
影响因子：
3.1
通讯作者：
Hess,GP
中科院分区：
文献类型：
--
作者：
Walker,JW;McNamee,MG;Pasquale,E;Cash,DJ;Hess,GP
用加利福尼亚电鳐（Torpedocalfornica）电器官制备的膜泡测定了乙酰胆碱受体控制离子流的失活率。使用时间分辨率为2毫秒的流动淬灭技术。将囊泡与氨甲酰胆碱预孵育不同时间，然后测量86 Rb+内流率。内流率随预孵育时间的延长而逐渐下降。这种内流率的降低（失活）发生在两个不同的时区。一个快速灭活过程的半衰期为300毫秒，导致至少60倍的离子通量率下降。剩余的离子通量活性在6-7秒的半衰期的缓慢失活过程中降低到不可检测的水平。以前，只有一个失活过程已被观察到的离子通量测量与受体丰富的囊泡从Electrophorus electricusorTorpedospecies。
The rates of inactivations of the acetylcholine receptor-controlled ion flux were measured with membrane vesicles prepared from the electric organ ofTorpedo californica. A flow quench technique with a time resolution of 2 msec was used. The vesicles were preincubated with carbamylcholine for various periods of time and then the rate of86Rb+influx was measured. The influx rate decreased progressively with the length of preincubation time. This decrease (inactivation) in influx rate occurred in two different time zones. A fast inactivation process with a half-time of ∼300 msec resulted in at least a 60-fold decrease of ion flux rate. The remaining ion flux activity decreased to an undetectable level in a slow inactivation process with a half-time of 6–7 seconds. Previously, only one inactivation process has been observed by ion flux measurements with receptor-rich vesicles fromElectrophorus electricusorTorpedospecies.