In the retina of RCS rats, GABA-like immunoreactivity was observed in the inner plexiform layer, few GABA-ergic amacrine cells and the ganglion cell layer.
As for ultrastructure, quantitative analysis showed that NPY-IR amacrinecell processes were most often presynaptic to NPY negative amacrinecell processes (49.7%) and ganglion cell dendrites (49.3%).