gamma-Aminobutyric acidA receptor heterogeneity in rat central nervous system: studies with clonazepam and other benzodiazepine ligands.

摘要: The properties of [3H]clonazepam, [3H]diazepam and [3H]zolpidem (N,N,6[trimethyl-2-(4-methyl-phenyl)imidazo[1,2-a]pyridine-3-acetamide hemitratrate) binding to synaptic membranes cerebellum, cortex, olfactory bulb, striatum spinal cord rat were compared the [3H]flunitrazepam, [3H]flumazenil [3H]midazolam. In cerebellar, cortical bulb membranes, density high-affinity sites all these tritiated benzodiazepine (BZ) ligands is almost identical. contrast, in striatum, [3H]clonazepam approximately 60 30%, respectively, [3H]diazepam, [3H]flunitrazepam or sites. number less than 20% for Moreover, displacement from by clonazepam zolpidem was characterized high IC50 values Hill slopes significantly 1. Because [3H]BZ ligand enhanced gamma-aminobutyric acid (GABA), data suggest that different regions central nervous system may contain GABA-BZ receptor subtypes. pharmacological clonazepam, diazepam (i.e., regarding their ability enhance bicuculline seizure threshold, decrease locomotor activity, induce ataxia elicit anticonflict action) further support concept preferential occupancy heterogeneous GABAA receptors drugs can be related effects on behavior.