GABA and glutamate as retina neurotransmitters in rabbit retina.

In summary, both glutamate and GABA appear to be functional neurotransmitters in the inner plexiform layer of the rabbit retina. Autoradiograph localization suggests they are both subpopulations of amacrine cells which are found primarily in the amacrine cell layer, although some appear as displaced amacrines in the ganglion cell layer. The characteristics of these two transmitter systems are similar to those described in brain including systems for transport, release and receptor binding. There is considerable evidence that GABAnergic cells may be responsible for the specificity of on-center ganglion cells through inhibitory modulation of cholinergic transmission. The role of glutamate is much more speculative at this point, however, it is suggested that the excitatory input to the GABAnergic neurons may be mediated by glutaminergic transmission.