The cholinergic amacrine cells of rabbit retina receive on and off input: an analysis of [3H]-ACh release using 2-amino-4-phosphonobutyric acid (APB) and chloride free medium.


Using the in vitro rabbit eye-cup we have examined the light-evoked release of ACh from cholinergic amacrine cells under conditions known to eliminate On responses in the retina. APB (100 microM), which blocks the photoreceptor/depolarizing bipolar cell synapse, reduced the light-evoked release of ACh by 80% but a small light-evoked response remained, which… (More)