Effect of calcium ion on the release of gamma-aminobutyric acid from synaptosomal fraction.
Brain synaptosomes released endogenous gamma-aminobutyric acid (GABA) in response to Ca2+. The release of GABA in response to 2.5 mM Ca2+ increased linearly with log[K+]0, showing that a membrane potential-dependent Ca2+ channel limits the GABA release. In the presence of Ca2+ ionophore, A23187, GABA release increased linearly with log[Ca2+]0 without altering the membrane potential of synaptosomes.
D000818:Animals; D001921:Brain / Q000378:metabolism; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D011188:Potassium / Q000502:physiology; D013574:Synaptosomes / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D000001:Calcimycin; D005680:gamma-Aminobutyric Acid; D011188:Potassium; D002118:Calcium