DeVries S H
Department of Ophthalmology and Visual Science, Houston Health Science Center, University of Texas, Houston, TX 77030, USA.
Neuron. 2001 Dec 20;32(6):1107-17. doi: 10.1016/s0896-6273(01)00535-9.
A proton pump acidifies synaptic vesicles and provides the electrochemical gradient for transmitter uptake. Although external protons can modulate membrane voltage- and ligand-gated conductances, the fate of the protons released when vesicles fuse with the plasma membrane is unclear. In the dark, the glutamate-laden vesicles of cone photoreceptors fuse continuously with the plasma membrane. I now show that vesicular protons feed back to block the nearby calcium channels that mediate release. This local proton-mediated feedback is a novel mechanism through which neurons may regulate the release of transmitter.
质子泵使突触小泡酸化，并为神经递质摄取提供电化学梯度。尽管外部质子可以调节膜电压门控和配体门控电导，但当小泡与质膜融合时释放的质子的去向尚不清楚。在黑暗中，视锥光感受器中充满谷氨酸的小泡与质膜持续融合。我现在发现，小泡中的质子会反馈回来阻断附近介导释放的钙通道。这种局部质子介导的反馈是神经元调节神经递质释放的一种新机制。
