CATECHOLAMINE-CONTAINING, INDOLEAMINE-CONTAINING, AND GABA-CONTAININGCELLS IN THE CHAMELEON RETINA

Neurons containing catecholamine, indoleamine, and gamma-aminobutyric acid (GABA) were identified by immunohistochemistry in the chameleon r etina. Tyrosine hydroxylase (TH) and serotonin (5HT) were observed mos tly in two subtypes of orthotopic amacrine cells differing in their so ma size and process distribution within the IPL. Some labelled cells w ere displaced either to the IPL (5HT) or to the GCL (TH and 5HT). A mu ltiplicity of retinal cell types contained GABA including cones, horiz ontal, amacrine, and ganglion tells. Our results confirmed those obtai ned in the retinas of other lizards except for the presence of interst itial and displaced amacrine cells containing TH or 5HT of which this is the first report.