[3H]diazepam binding sites on chick neurons in primary culture

High affinity [3H]diazepam binding sites were identified on neurons prepared from the hemispheres of 8-day-old chick embryos and grown in serum-containing or serum-free medium. Clonazepam (IC50 = 3 nM) was more potent than Ro 5-4864 (IC50 greater than 1000 nM) in displacing [3H]diazepam binding. GABA and pentobarbital, in the presence of chloride ions were able to stimulate [3H]diazepam binding synergistically. These interactions were found to be comparable to those observed in mammalian brain.