Benzodiazepine binding in chicken retina and its interaction with gamma-aminobutyric acid

Chicken retina contains saturable, stereoselective high affinity binding sites for benzodiazepines. The density of binding sites in chicken retina exceeds that found in rat and cow retina. GABA and muscimol increase specific 3H-flunitrazepam binding in the chicken retina in a dose-dependent manner. This effect is reversed by bicuculline methiodide. The enhancement of specific binding caused by GABA was shown to be due to an increase in the affinity of flunitrazepam, while the number of binding sites remained unchanged.