A rebound-like pattern of REM sleep induced by guinea pig myelin basic protein (MBP) in cats

In order to investigate the effects of myelin basic protein (MBP) on sleep parameters, adult cats received 10 micrograms of guinea pig MBP into the third ventricle of the brain and were subsequently recorded for 8 hours. In comparison with both saline solution (0.1 ml) and 10 micrograms basic proteins (protamines and histones), MBP specifically produced a rebound-like pattern of the REM sleep (REMS); it decreased the REMS latency, increased the number of REMS episodes and dramatically increased the REMS percent during the 3rd and 6th hour of recording. In the light of the strong depolarisation effect and of the presence of specific binding sites for serotonin, the results are discussed as suggesting that MBP enhances the REMS triggering mechanisms.