PT  - JOURNAL ARTICLE
AU  - Steven L. Coon
AU  - Susan K. McCune
AU  - David Sugden
AU  - David C. Klein
TI  - Regulation of Pineal α<sub>1B</sub>-Adrenergic Receptor mRNA: Day/Night Rhythm and β-Adrenergic Receptor/Cyclic AMP Control
AID  - 10.1124/mol.51.4.551
DP  - 1997 Apr 01
TA  - Molecular Pharmacology
PG  - 551--557
VI  - 51
IP  - 4
4099  - http://molpharm.aspetjournals.org/content/51/4/551.short
4100  - http://molpharm.aspetjournals.org/content/51/4/551.full
SO  - Mol Pharmacol1997 Apr 01; 51
AB  - Mammalian pineal function is regulated by norepinephrine acting through α1B- and β1-adrenergic receptors (ARs). Noradrenergic stimulation of α1B-ARs potentiates the β1-AR-driven increase in cAMP, serotoninN-acetyltransferase, and melatonin production. In the present study, we describe a 3-fold daily rhythm in mRNA-encoding α1B-ARs in the pineal gland, with a peak at midnight. Pharmacological studies indicate that this increase in α1B-AR mRNA is due to activation of β-ARs. Second messenger studies indicate that α1B-AR mRNA is increased by agents that increase cAMP, including dibutyryl cAMP, cholera toxin, forskolin, or vasoactive intestinal peptide. These observations indicate that α1B-AR mRNA can be physiologically regulated by a β-AR-dependent enhancement of cAMP. It also was observed that in vivo and in vitrochanges in α1B-AR mRNA are not accompanied by similar changes in α1B-AR binding, indicating that turnover of α1B-AR protein is significantly slower than that of α1B-AR mRNA and that post-transcriptional mechanisms play an important role in regulating α1B-AR binding.