Potassium-Stimulated Release of Taurine in a Crude Retinal Preparation Obtained from the Rat is Calcium Independent
The role of taurine as a potential neurotransmitter in the retina has been questioned in numerous literature reports. Thus, crude retinal homogenates prepared from rat retina were preloaded with [3H]taurine under either high-or low-affinity uptake conditions and were then subjected to superfusion techniques to determine whether KC1 (56 mM), veratridine (100 μM), 4-aminopyridine (1 mM), or LiC1 (56 mM3) could evoke the release of [3H]taurine. Dependence of the K+-evoked release of [3H]taurine on Ca2+ was also measured since one of the essential criteria for a neurotransmitter is Ca2+-dependent release of the substance from presynaptic nerve terminals.
KeywordsSucrose Manifold Lithium Pyridine Retina
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