Specific binding of ligand to rat forebrain alpha- and beta-adrenergic, muscarinic cholinergic, opiate, benzodiazepine, and striatal dopamine receptors was measured at 4-hour intervals during the last 13 hours of a 24-hour sleep deprivation period, and during the first 11 hours of the recovery sleep period. In non-sleep-deprived controls a 24-hour rhythm in binding was evident. The minor differences between the sleep deprivation group and the control group consisted mainly in a reduced amplitude of the 24-hour rhythm under the sleep deprivation schedule. The results indicate that neither the 24-hour forced locomotion nor the subsequent prominent sleep rebound is accompanied by marked changes in the number of neurotransmitter receptors and their circadian rhythms.
