REM-SLEEP DEPRIVATION INDUCES GALANIN GENE-EXPRESSION IN THE RAT-BRAIN

Rats were deprived of REM sleep for 24 h by keeping them on small plat forms that were placed in a water bath (the platform method). Galanin coding mRNA was visualized using in situ hybridization, and cells expr essing galanin mRNA were counted. In REM sleep-deprived animals the ce ll count was higher in the preoptic area and periventricular nucleus. Lesions of this area have been reported to induce wakefulness in cats and rats. Galanin administered into the lateral ventricle had no effec t on sleep. We conclude that REM sleep deprivation can induce galanin gene expression in some brain areas, but galanin alone does not modify spontaneous sleep.