Pentobarbital blocks the stress-induced decrease in [3H]Ro 5-4864 binding in rat kidney.

Exposure to environmental stress causes changes in the binding of [3H]Ro 5-4864 to peripheral benzodiazepine receptors (PBRs). The influence of the central nervous system (CNS) in these stress-induced modifications is unclear. The present study examined whether pretreatment with a dose-response regimen of sodium pentobarbital would impact the stress-induced reduction in renal PBR. Administration of either a sedative/ataxic (20 mg/kg) or hypnotic (60 mg/kg) dose of pentobarbital prior to stress blocks the stress-induced decrease of [3H]Ro 5-4864 binding to renal PBR in rat. These findings suggest that higher-order, supraspinal mechanisms play a critical role in marshalling the renal PBR changes in response to stress.