Mechanism of noradrenaline-induced stimulation of Na–K ATPase activity in the rat brain: implications on REM sleep deprivation-induced increase in brain excitability

Rapid eye movement (REM) sleep is a unique phenomenon expressed in all higher forms of animals. Its quantity varies in different species and with ageing; it is also affected in several psycho-somatic disorders. Several lines of studies showed that after REM sleep loss, the levels of noradrenaline (NA) increase in the brain. The NA in the brain modulates neuronal Na–K ATPase activity, which helps maintaining the brain excitability status. The detailed mechanism of increase in NA level after REM sleep loss and the effect of NA on stimulation of Na–K ATPase in the neurons have been discussed. The findings have been reviewed and discussed with an aim to understand the role of REM sleep in maintaining brain excitability status.