Popova E, Mitova L, Vitanova L, Kupenova P
Department of Physiology, Medical University, Sofia, Bulgaria.
Comp Biochem Physiol C Toxicol Pharmacol. 2000 Jun;126(2):139-51. doi: 10.1016/s0742-8413(00)00107-9.
Perfusion with the ON channel blocker 2-amino-4-phosphonobutyrate (APB) of dark adapted frog eyecups not only abolished the ganglion cells' (GC) ON responses and the ERG b-wave, but markedly potentiated the OFF responses of ON-OFF and phasic OFF-GCs and the d-wave amplitude of simultaneously recorded local ERG. Glycinergic blockade by strychnine prevented this potentiating effect in 31 out of 69 GCs, but did not change it at all in the other cells. At the same time the d-wave potentiation was preserved during the glycinergic blockade in all eyecups. The results indicate that glycinergic transmission is involved in the inhibition exerted from ON upon OFF channel in some but not all frog retinal GCs.
