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. 1986 Mar;83(6):1743–1746. doi: 10.1073/pnas.83.6.1743

Norepinephrine-induced alteration in the coupling of alpha 1-adrenergic receptor occupancy to calcium efflux in rabbit aortic smooth muscle cells.

W S Colucci, R W Alexander
PMCID: PMC323160  PMID: 3006068

Abstract

To determine whether alpha-adrenergic desensitization of vascular smooth muscle is due to an alteration in alpha 1-adrenergic receptor coupling, we determined the relationship between receptor occupancy and maximal receptor-coupled Ca2+ efflux in cultured rabbit aortic smooth muscle cells (i) under basal conditions as defined by receptor inactivation with phenoxybenzamine and (ii) after 48 hr of exposure to several concentrations of 1-norepinephrine (NE). Neither phenoxybenzamine nor NE exposure caused a change in binding affinity for [3H]prazosin or NE. Maximal [3H]prazosin binding capacity and maximal NE-stimulated 45Ca2+ efflux decreased progressively with exposure of incubated cells to increasing concentrations of phenoxybenzamine or NE. An approximately 80% decrease in maximal [3H]prazosin binding capacity caused by either phenoxybenzamine or NE resulted in complete loss of NE-stimulated 45Ca2+ efflux, indicating that under these conditions approximately 20% of alpha 1-adrenergic receptors are not coupled to the Ca2+ efflux. Under basal conditions, the relationship between maximal [3H]prazosin binding capacity and maximal NE-stimulated 45Ca2+ efflux was markedly nonlinear, so that a near maximal response could be elicited by occupancy of only approximately 40% of the receptors. In contrast, after a 48-hr incubation of cells with NE, occupancy-response coupling was considerably less efficient, so that even full occupancy of the 35% of receptors that remained after NE exposure resulted in only approximately 20% of maximal NE-stimulated 45Ca2+ efflux. Thus, an alteration in occupancy-response coupling at a step proximal to Ca2+ mobilization and/or influx, rather than a reduction in receptor number, is of primary importance in the process of agonist-induced alpha-adrenergic receptor desensitization of vascular smooth muscle cells.

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Selected References

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  1. Alexander R. W., Brock T. A., Gimbrone M. A., Jr, Rittenhouse S. E. Angiotensin increases inositol trisphosphate and calcium in vascular smooth muscle. Hypertension. 1985 May-Jun;7(3 Pt 1):447–451. [PubMed] [Google Scholar]
  2. Berridge M. J., Irvine R. F. Inositol trisphosphate, a novel second messenger in cellular signal transduction. Nature. 1984 Nov 22;312(5992):315–321. doi: 10.1038/312315a0. [DOI] [PubMed] [Google Scholar]
  3. Besse J. C., Furchgott R. F. Dissociation constants and relative efficacies of agonists acting on alpha adrenergic receptors in rabbit aorta. J Pharmacol Exp Ther. 1976 Apr;197(1):66–78. [PubMed] [Google Scholar]
  4. Chan T. M., Blackmore P. F., Steiner K. E., Exton J. H. Effects of adrenalectomy on hormone action on hepatic glucose metabolism. Reciprocal change in alpha- and beta-adrenergic activation of hepatic glycogen phosphorylase and calcium mobilization in adrenalectomized rats. J Biol Chem. 1979 Apr 10;254(7):2428–2433. [PubMed] [Google Scholar]
  5. Colucci W. S., Brock T. A., Gimbrone M. A., Jr, Alexander R. W. Nonlinear relationship between alpha 1-adrenergic receptor occupancy and norepinephrine-stimulated calcium flux in cultured vascular smooth muscle cells. Mol Pharmacol. 1985 May;27(5):517–524. [PubMed] [Google Scholar]
  6. Colucci W. S., Gimbrone M. A., Jr, Alexander R. W. Regulation of the postsynaptic alpha-adrenergic receptor in rat mesenteric artery. Effects of chemical sympathectomy and epinephrine treatment. Circ Res. 1981 Jan;48(1):104–111. doi: 10.1161/01.res.48.1.104. [DOI] [PubMed] [Google Scholar]
  7. Danthuluri N. R., Deth R. C. Phorbol ester-induced contraction of arterial smooth muscle and inhibition of alpha-adrenergic response. Biochem Biophys Res Commun. 1984 Dec 28;125(3):1103–1109. doi: 10.1016/0006-291x(84)91397-4. [DOI] [PubMed] [Google Scholar]
  8. Ito H., Baum B. J., Uchida T., Hoopes M. T., Bodner L., Roth G. S. Modulation of rat parotid cell alpha-adrenergic responsiveness at a step subsequent to receptor activation. J Biol Chem. 1982 Aug 25;257(16):9532–9538. [PubMed] [Google Scholar]
  9. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  10. Leeb-Lundberg L. M., Cotecchia S., Lomasney J. W., DeBernardis J. F., Lefkowitz R. J., Caron M. G. Phorbol esters promote alpha 1-adrenergic receptor phosphorylation and receptor uncoupling from inositol phospholipid metabolism. Proc Natl Acad Sci U S A. 1985 Sep;82(17):5651–5655. doi: 10.1073/pnas.82.17.5651. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Lurie K. G., Tsujimoto G., Hoffman B. B. Desensitization of alpha-1 adrenergic receptor-mediated vascular smooth muscle contraction. J Pharmacol Exp Ther. 1985 Jul;234(1):147–152. [PubMed] [Google Scholar]
  12. Mauger J. P., Sladeczek F., Bockaert J. Characteristics and metabolism of alpha 1 adrenergic receptors in a nonfusing muscle cell line. J Biol Chem. 1982 Jan 25;257(2):875–879. [PubMed] [Google Scholar]
  13. Munson P. J., Rodbard D. Ligand: a versatile computerized approach for characterization of ligand-binding systems. Anal Biochem. 1980 Sep 1;107(1):220–239. doi: 10.1016/0003-2697(80)90515-1. [DOI] [PubMed] [Google Scholar]
  14. Nabika T., Velletri P. A., Lovenberg W., Beaven M. A. Increase in cytosolic calcium and phosphoinositide metabolism induced by angiotensin II and [Arg]vasopressin in vascular smooth muscle cells. J Biol Chem. 1985 Apr 25;260(8):4661–4670. [PubMed] [Google Scholar]
  15. Nishizuka Y. The role of protein kinase C in cell surface signal transduction and tumour promotion. Nature. 1984 Apr 19;308(5961):693–698. doi: 10.1038/308693a0. [DOI] [PubMed] [Google Scholar]
  16. Purdy R. E., Stupecky G. L. Characterization of the alpha adrenergic receptor properties of rabbit ear artery and thoracic aorta. J Pharmacol Exp Ther. 1984 May;229(2):459–468. [PubMed] [Google Scholar]
  17. Rasmussen H., Forder J., Kojima I., Scriabine A. TPA-induced contraction of isolated rabbit vascular smooth muscle. Biochem Biophys Res Commun. 1984 Jul 31;122(2):776–784. doi: 10.1016/s0006-291x(84)80101-1. [DOI] [PubMed] [Google Scholar]
  18. Schwarz K. R., Lanier S. M., Carter E. A., Graham R. M., Homcy C. J. Transient high-affinity binding of agonists to alpha 1-adrenergic receptors of intact liver cells. FEBS Lett. 1985 Aug 5;187(2):205–210. doi: 10.1016/0014-5793(85)81243-6. [DOI] [PubMed] [Google Scholar]
  19. Sladeczek F., Bockaert J., Mauger J. P. Differences between agonist and antagonist binding to alpha 1-adrenergic receptors of intact and broken-cell preparations. Mol Pharmacol. 1983 Nov;24(3):392–397. [PubMed] [Google Scholar]
  20. Suematsu E., Hirata M., Hashimoto T., Kuriyama H. Inositol 1,4,5-trisphosphate releases Ca2+ from intracellular store sites in skinned single cells of porcine coronary artery. Biochem Biophys Res Commun. 1984 Apr 30;120(2):481–485. doi: 10.1016/0006-291x(84)91279-8. [DOI] [PubMed] [Google Scholar]
  21. Wallenstein S., Zucker C. L., Fleiss J. L. Some statistical methods useful in circulation research. Circ Res. 1980 Jul;47(1):1–9. doi: 10.1161/01.res.47.1.1. [DOI] [PubMed] [Google Scholar]
  22. Wikberg J. E., Akers M., Caron M. G., Hagen P. O. Norepinephrine-induced down regulation of alpha 1 adrenergic receptors in cultured rabbit aorta smooth muscle cells. Life Sci. 1983 Oct 3;33(14):1409–1417. doi: 10.1016/0024-3205(83)90824-x. [DOI] [PubMed] [Google Scholar]

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