Atypical synergistic alpha 1- and beta-adrenergic regulation of adenosine 3',5'-monophosphate and guanosine 3',5'-monophosphate in rat pinealocytes

Endocrinology. 1985 Jun;116(6):2167-73. doi: 10.1210/endo-116-6-2167.


The adrenergic control of cAMP and 3',5'-cyclic GMP (cGMP) in dispersed adult rat pinealocytes was investigated. Norepinephrine treatment increased cAMP and cGMP content 60- and 400-fold, respectively; both alpha- and beta-adrenoceptors had to be activated for these responses to occur. Beta-Adrenergic stimulation alone produced only about 6- and 2-fold increase in cAMP and cGMP content, respectively. Alpha-Adrenergic stimulation, which alone had no effect on either cyclic nucleotide concentration, markedly amplified the beta-adrenergic stimulation of both cAMP and cGMP. The relative potency of alpha-adrenergic agonists and antagonists indicates the alpha 1-subclass of adrenoceptors is involved. A role of alpha 1-adrenoceptors in the control of pineal cAMP is consistent with published evidence of the presence of alpha 1-adrenoceptors on pinealocytes and their role in the regulation of N-acetyltransferase activity and melatonin production.

MeSH terms

  • Animals
  • Cyclic AMP / analysis*
  • Cyclic GMP / analysis*
  • Dose-Response Relationship, Drug
  • Female
  • In Vitro Techniques
  • Norepinephrine / pharmacology
  • Pineal Gland / analysis*
  • Pineal Gland / drug effects
  • Rats
  • Receptors, Adrenergic, alpha / physiology*
  • Receptors, Adrenergic, beta / physiology*
  • Sympatholytics / pharmacology
  • Sympathomimetics / pharmacology
  • Time Factors


  • Receptors, Adrenergic, alpha
  • Receptors, Adrenergic, beta
  • Sympatholytics
  • Sympathomimetics
  • Cyclic AMP
  • Cyclic GMP
  • Norepinephrine