Properties of [3H]taurine release from crude synaptosomal fractions of rat cerebral cortex.
The release of previously accumulated [3H]taurine and [14C]GABA from crude synaptosomal (P2) fractions isolated from rat cerebral cortex was studied using a superfusion system. The spontaneous efflux of [3H]taurine and [14C]GABA was stimulated by elevated concentrations of K+ (15--133 mM) in a concentration-dependent manner. This K+-stimulated relase of [14C]Gaba but not of [3H]taurine was enhanced in the presence of Ca2+. However, addition of 3 mM Ca2+ to the superfusion medium in the presence of the ionophore A 23187 resulted in a stimulation of the release of both [3H]taurine and [14C]GABA. These results are discussed in connection with the cellular localization of taurine in the central nervous system.
D000818:Animals; D001692:Biological Transport; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D002540:Cerebral Cortex / Q000378:metabolism*; D008297:Male; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism*; D013654:Taurine / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D013654:Taurine; D000001:Calcimycin; D005680:gamma-Aminobutyric Acid; D011188:Potassium; D002118:Calcium