Colocalization of [3H]muscimol and antisera to GABA and glutamic acid decarboxylase within the same neurons in monkey retina.

Two procedures have been used to test for the colocalization of different neuroanatomical gamma-aminobutyric acid (GABA)ergic markers within the same neurons in primate retina. First, sequential immunocytochemical processing of sections was done using antisera to glutamic acid decarboxylase and to GABA, and these antisera were visualized by peroxidase-antiperoxidase and fluorescein isothiocyanate techniques respectively. Colocalization of both antisera was found within the same neuron cell bodies. In the second experiment, immunocytochemical staining using GABA antiserum was performed on retinal tissue that had been previously incubated in vitro for neuronal uptake of [3H]muscimol. Both markers colocalized in 70% of the labeled cell body population.