POSITIVE CORRELATIONS BETWEEN CEREBRAL PROTEIN-SYNTHESIS RATES AND DEEP SLEEP IN MACACA-MULATTA

Local rates of cerebral protein synthesis (ICPSleu) were determined wi th the autoradiographic L-[1-C-14]leucine method in seven awake and se ven asleep, adult rhesus monkeys conditioned to sleep in a restraining chair in a darkened, ventilated chamber while EEG., EGG, and EMG were monitored. Prior to the period of measurement all animals slept for 1 -4 h. Controls were awakened after at least one period of rapid-eye-mo vement (REM) sleep. Experimental animals were allowed to remain asleep , and they exhibited non-REM sleep for 71-99% of the experimental peri od. Statistically significant differences in ICPSleu between control a nd experimental animals were found in four of the 57 regions of brain examined, but these effects may have occurred by chance. In the sleepi ng animals, however, correlations between ICPSleu and percent time in deep sleep were positive in all regions and were statistically signifi cant (P less than or equal to 0.05) in 35 of the regions. When time in deep sleep was weighted for the integrated specific activity of leuci ne in grey matter, positive correlations were statistically significan t (P less than or equal to 0.05) in 18 regions in the experimental ani mals. These results suggest that rates of protein synthesis are increa sed in many regions of the brain during deep sleep compared with light sleep.