Paradoxical sleep deprivation increases glutamine synthetase in rat brain

The modifications of glutamine synthetase (GS) level, an enzyme mainly located in astrocytes, were investigated in rat after paradoxical sleep deprivation and during recovery. An immunotitration method was used to evaluate the relative level of GS in brain tissue. At the end of a 24 hrs. paradoxical sleep deprivation, a significant increase in GS level was observed both in the frontoparietal cortex and the locus coeruleus area. 4 hrs. later, during recovery, the GS level returned to control level in the cortex but was lower in the locus coeruleus area.