Modulation of GABA release by nitric oxide in the chick retina: Different effects of nitric oxide depending on the cell population

摘要: Abstract γ-Aminobutyric acid (GABA) is considered to be the most important inhibitory neurotransmitter in central nervous system, including retina. It has been shown that nitric oxide (NO) can influence physiology of all retinal neuronal types, by mechanisms modulation GABA release. However, until now, there have no data concerning effects on endogenous release NO produced cells intact In present study, we investigated how production induced drugs influences retina mature chicken. Retinas were exposed different affect production, and remaining tissue was detected immunohistochemical procedures. A specific nNOS inhibitor (7-NI) reduced number GABA + amacrine ganglion cell layer (GCL) 33% 41%, respectively. transporter blocked this effect. L -arginine (100 μM), precursor NO, increases 62% 34% GCL cells, sodium (Na+)-free solution, 7-NI a PKG prevented effect (100 μM). higher concentration (1 mM) 35% reduction GABA + cells Na+-dependent mechanism restricted population. NMDA, which stimulates increased as indicated 53% 38% reductions This only cells. We conclude basal moderate (possibly -arginine; 100 μM) inhibit from amacrine NMDA or induce NO-dependent increase possibly stimulating production.