Effects of quazepam and flurazepam on gaba-ergic transmission in mouse cerebellum: Relationship between biochemical and behavioral activity

Summary Effects on GABA transmission in mouse cerebellum were investigated after administration of two benzodiazepine hypnotics: quazepam (SCH 16134) and flurazepam. Both drugs at a similar dose range induced a dose-related decrease of cerebellar cGMP content. Biochemical effects were long-lasting with a complete recovery of normal values after 24 hours. Quazepam and flurazepam counteracted the rise of cGMP and the decrease of GABA in cerebellum elicited by isoniazid. Anticonvulsant activity was long-lasting and quazepam was more active than flurazepam at various times after administration. Spontaneous motor activity was depressed up to 16 hours following quazepam, but it was unmodified by flurazepam administered at the same dose which produced cGMP lowering. These findings provide little support for a correlation between changes of cGMP content in cerebellum and impairment of motor function produced by benzodiazepines.