Lower environmental temperature: effect of long-term exposure on diazepam-induced changes in brain GABA

Long-term diazepam (DZ) treatment (5 mg/kg, i.p. for 15-30 consecutive days) reduced GABAergic activity in hypothalamus and cerebellum with the alteration of GABA synthesis and its release process. This long-term DZ-induced inhibition in GABAergic activity in hypothalamus and cerebellum was not altered when DZ-treated rats were exposed (2 h/day) to lower environmental temperature (LET; 12 degrees C) for 7-30 consecutive days. Although repeated exposure to LET did not affect the GABA system in cerebellum and hypothalamus, striatal GABAergic activity was significantly enhanced under similar conditions. This LET-induced (repeated exposure) stimulation in striatal GABAergic activity was prevented when rats were treated with DZ along with repeated LET exposure (2 h/day) under long-term conditions.