Differential localization of GABA(A) receptor α and β subunits in the hamster retina and relationship with glutamic acid decarboxylase immunoreactivity

In order to determine the cellular localization of GABA(A)α and β subunits in the hamster retina, single and double immunocytochemistry was performed in perfuse-fixed hamster retina using commercially-available antibodies against the two receptor subunits and glutamic acid decarboxylase. Strong GABA(A)β immunoreactivity was found in two strata of the inner plexiform layer and in perikarya of amacrine bells and bipolar cells in the inner nuclear layer. In contrast, no GABA(A)α immunoreactivity was detected. All but a few of the GABA(A)β-immunoreactive amacrine cells were found not to display glutamic acid decarboxylase immunoreactivity. The present results indicate that there is a differential localization of GABA(A)α and β subunits in different neuronal subpopulations in the hamster retina.