Nitric oxide mediates NMDA-evoked [H-3]GABA release from chick retina cells

The stimulation of NMDA receptor increased [H-3]GABA release from preloaded cultured retina cells. This effect appears to be mediated by NO production, since addition of L-NA reduces NMDA-evoked [H-3]GABA release. Spermine/ NO complex, an NO donor, mimics the effect produced by NMDA, The addition of zaprinast, a phosphodiesterase inhibitor, as well as 8-Br-cGMP enhances the NMDA-evoked [H-3]GABA release. These results agree with the existence in chick retina cells of NO/cGMP pathways and support a role for NO in NMDA-evoked events, The activation of this receptor complex through maturative stages of the retina together with the NO-mediated increase in GABA release may account for NMDA differentiative effect in culturing retina cells. (C) 1997 Federation of European Biochemical Societies.