Rapid eye movement sleep deprivation impairs hippocampus-dependent spatial memory: involvement of GABAergic receptors

Abstract

Background: This study examined the effect of rapid eye movement (REM) sleep deprivation on spatial memory in Wistar rats and the role of GABAergic receptors.

Methods: A total of thirty-six age matched male Wistar rats weighing 170-200g were grouped into six (A-F) of six animals each. Group A served as control, Group B was sleep deprived, rats in groups C-F in addition to being sleep deprived for 72 hrs, received Diazepam (1mg/kg) (C), Baclofen (5mg/kg) (D), Phaclofen (1mg/kg) (E), Bicuculline (2mg/kg) (F) respectively. Spatial memory was accessed using Morris water maize (MWM) while motor performance (MP) and working memory were accessed using Y-Maze. Some serum biochemical parameters were also assessed.

Results: These showed that spatial memory was decreased in the sleep deprived group compared with control (p<0.05). Diazepam increased, while Bicuculline decreased time latency in the MWM compared with sleep-deprived group (p<0.05). MP in the Y maze was significantly reduced (p<0.05) in all groups compared with control. Serum Creatine kinase (CK) and calcium as well as hippocampal CK were significantly (p<0.05) increased in the sleep-deprived group compared with control.

Conclusion: REM sleep deprivation produced impairment in spatial memory in rats which is at least in part mediated by Gabaergic mechanisms with GABA A receptors being more implicated than the B subtype.

Keywords: Rapid eye movement sleep, sleep deprivation, spatial memory, GABA receptors