title: Regulation of pineal alpha1B-adrenergic receptor mRNA: day/night rhythm and beta-adrenergic receptor/cyclic AMP control.
abstract: Mammalian pineal function is regulated by norepinephrine acting through alpha1beta- and beta1-adrenergic receptors (ARs). Noradrenergic stimulation of alpha1beta-ARs potentiates the beta1-AR-driven increase in cAMP, serotonin N-acetyltransferase, and melatonin production. In the present study, we describe a 3-fold daily rhythm in mRNA-encoding alpha1beta-ARs in the pineal gland, with a peak at midnight. Pharmacological studies indicate that this increase in alpha1beta-AR mRNA is due to activation of beta-ARs. Second messenger studies indicate that alpha1beta-AR mRNA is increased by agents that increase cAMP, including dibutyryl cAMP, cholera toxin, forskolin, or vasoactive intestinal peptide. These observations indicate that alpha1beta-AR mRNA can be physiologically regulated by a beta-AR-dependent enhancement of cAMP. It also was observed that in vivo and in vitro changes in alpha1beta-AR mRNA are not accompanied by similar changes in alpha1beta-AR binding, indicating that turnover of alpha1beta-AR protein is significantly slower than that of alpha1beta-AR mRNA and that post-transcriptional mechanisms play an important role in regulating alpha1beta-AR binding.
authors.affiliation: Laboratory of Developmental Neurobiology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Coon
authors.forename: S K
authors.initials: SK
authors.lastname: McCune
authors.forename: D
authors.initials: D
authors.lastname: Sugden
authors.forename: D C
authors.initials: DC
authors.lastname: Klein
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D002772:Cholera Toxin / Q000494:pharmacology; D002940:Circadian Rhythm / Q000502:physiology*; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000096:biosynthesis / Q000378:metabolism*; D005260:Female; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D010870:Pineal Gland / Q000378:metabolism* / Q000648:ultrastructure; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018340:Receptors, Adrenergic, alpha-1 / Q000096:biosynthesis / Q000378:metabolism*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology / Q000502:physiology
chemical_list: C547716:ADRA1B protein, human; D000316:Adrenergic alpha-Agonists; D000318:Adrenergic beta-Agonists; D012333:RNA, Messenger; D018340:Receptors, Adrenergic, alpha-1; D005576:Colforsin; D010656:Phenylephrine; D014660:Vasoactive Intestinal Peptide; D002772:Cholera Toxin; D000242:Cyclic AMP; D007545:Isoproterenol; D009638:Norepinephrine