Beta1-adrenoceptors in rat anterior pituitary may be constitutively active. Inverse agonism of CGP 20712A on basal 3',5'-cyclic adenosine 5'-monophosphate levels

Endocrinology
Kristel JanssensC Denef

Abstract

Catecholamines directly stimulate GH, ACTH, and prolactin secretion from rat anterior pituitary through the beta(2)-adrenoceptor (AR). We recently showed that gonadotrophs express the beta(1)-AR and that glucocorticoids drastically increase its mRNA expression level. The present investigation explores whether beta(1)-ARs are functionally coupled to adenylate cyclase. In anterior pituitary cell aggregates, the highly selective beta(1)-AR antagonists CGP 20712A and ICI 89,406-8a attenuated isoproterenol-stimulated cAMP accumulation, but no agonist action of norepinephrine could be detected. Remarkably, CGP 20712A inhibited basal cAMP levels by its own for at least 50%, an action that tended to be more effective in dexamethasone-supplemented medium. The latter effect was abolished by the beta-AR antagonist carvedilol, but not by other beta-AR antagonists. Pretreatment with pertussis toxin abolished the action of CGP 20712A on basal cAMP. CGP 20712A also attenuated isoproterenol-induced cAMP accumulation in the gonadotroph cell lines alphaT3-1 and LbetaT2, but not in the somatotroph precursor cell line GHFT and the folliculo-stellate cell line TtT/GF. However, in LbetaT2 cells CGP 20712A did not inhibit basal cAMP levels by its own...Continue Reading

References

May 1, 1977·Proceedings of the National Academy of Sciences of the United States of America·J A MartialP H Seeburg
Jun 1, 1977·Proceedings of the National Academy of Sciences of the United States of America·R J TushinskiF C Bancroft
Dec 30, 1992·Biochemical and Biophysical Research Communications·N SchusslerN F Biguet
Oct 1, 1992·Trends in Biochemical Sciences·J R Hepler, A G Gilman
Jan 1, 1989·Methods in Enzymology·C DenefP Carmeliet
Nov 1, 1985·Endocrinology·S N PerkinsM J Cronin
Jan 1, 1986·Advances in Experimental Medicine and Biology·E P SlaterJ D Baxter
May 1, 1987·Neuroendocrinology·M GambaccianiD D Rasmussen
Nov 1, 1983·Proceedings of the National Academy of Sciences of the United States of America·E MezeyJ Axelrod
Dec 1, 1994·Gynecological Endocrinology : the Official Journal of the International Society of Gynecological Endocrinology·W G Rossmanith, M Gambacciani
Apr 5, 1996·Cell·Z ZhangE Ruoslahti
Jul 15, 1996·The Journal of Clinical Investigation·C GauthierH Le Marec
Nov 17, 1998·American Journal of Respiratory and Critical Care Medicine·M Johnson
Jan 12, 1999·Frontiers in Neuroendocrinology·E ArztG K Stalla
Sep 3, 1999·FEBS Letters·A LattionS Cotecchia
Jun 30, 2001·Trends in Pharmacological Sciences·M J Marinissen, J S Gutkind
Oct 30, 2001·Pflügers Archiv : European journal of physiology·P AlarcónJ García-Sancho

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Citations

Apr 1, 2014·Pharmacology Research & Perspectives·Rhonda L CarterDouglas G Tilley
Jun 27, 2008·Toxicological Sciences : an Official Journal of the Society of Toxicology·Richard M Sharpe
Apr 10, 2009·Toxicological Sciences : an Official Journal of the Society of Toxicology·Karen H WatanabeNancy D Denslow
Aug 23, 2020·Cells·Martin C MichelPeter Hein

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