Heterogeneous effects of rapid eye movement sleep deprivation on binding to α- and β-adrenergic receptor subtypes in rat brain

Quantitative receptor autoradiography was used to map alterations in binding to alpha(1)-, alpha(2)-, beta(1)- and beta(2)-adrenergic receptors throughout the brain of rats deprived of rapid eye movement sleep for 96 h. Binding of [H-3]prazosin to alpha(1) sites, while nor significantly different in any of 46 brain regions examined, showed a clear overall tendency towards decreased values after sleep deprivation. [H-3]UK-14,314-labeled cc, binding sites were not significantly affected by sleep deprivation in any of 91 brain regions analysed, despite a trend towards increased values. In contrast, P-adrenergic binding was significantly reduced throughout the brain. Binding to beta(1) sites labeled by [I-125]iodopindolol in the presence of ICI-11855 was significantly reduced in 13 of 69 brain areas examined; binding to beta(2) sites labeled by [I-125]iodopindolol in the presence of CGP-20712A was likewise reduced throughout the brain and significantly so in 25 of the 72 brain areas analysed. Rank ordering of the binding changes indicated that reductions in beta(1) vs beta(2) binding were maximal in different brain areas. This pattern of results may reflect a particular configuration of effects specifically associated with sleep loss stress. The results are consistent with evidence of persisting noradrenergic cell activity during sleep deprivation. The observed heterogeneity of effects suggests that not all norepinephrine receptors are equally affected by rapid eye movement sleep deprivation. (C) 1998 IBRO. Published by Elsevier Science Ltd.