DIAZEPAM MODULATES THE PERIOD OF LOCOMOTOR RHYTHM IN MICE (MUS BOODUGA) AND ATTENUATES LIGHT-INDUCED PHASE ADVANCES

Experiments were carried out on the continuous action of diazepam (ben zodiazepine) offered through drinking water in 2% ethanol on psi and t au of the activity rhythms under LD (12: 12) and DD conditions. Under entraining conditions diazepam failed to evoke striking changes in psi . On the other hand, under free-running conditions period-lengthening and period-shortening effects were observed. Further experiments condu cted on the continuous effect of diazepam on light pulse evoked phase shifts revealed that phase advances were attenuated significantly in d iazepam-treated animals at CT 20 and 24. These results were discussed with regard to the action of diazepam on the light sensitivity of the circadian pacemaker.