Skip to main content
PMC home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1992 Feb;447:275–292. doi: 10.1113/jphysiol.1992.sp019002

Alpha 1-adrenergic effects on intracellular pH and calcium and on myofilaments in single rat cardiac cells.

A Terzic 1, M Pucéat 1, O Clément 1, F Scamps 1, G Vassort 1
PMCID: PMC1176036  PMID: 1317431

Abstract

1. The cellular effects of alpha 1-adrenoceptor stimulation by phenylephrine were studied in the presence of propranolol in single cells isolated from the ventricles of rat hearts. 2. Phenylephrine (10-100 microM) induced a biphasic pattern of inotropism in these cells: a transient negative followed by a sustained positive inotropic effect as usually observed in cardiac tissues. 3. In Snarf-1-loaded cells, phenylephrine induced an alkalinization. This effect was reversible on wash-out and inhibited by prazosin, an alpha 1-adrenoceptor antagonist. 4. The alpha 1-adrenoceptor-mediated increase in intracellular pH (pHi) was 0.1 pH unit in HEPES buffer containing 4.4 mM-NaHCO3 and in Krebs buffer containing 25 mM-NaHCO3. 5. The alkalinization was blocked by the Na(+)-H+ antiport blocker, ethylisopropylamiloride (EIPA). 6. The recovery from an acidosis induced by a NH4Cl pre-pulse was accelerated by phenylephrine. The phenylephrine-induced alkalinization was attributed to activation of the Na(+)-H+ antiport. 7. Despite its ability to increase pHi, phenylephrine did not alter Ca2+ current amplitude and kinetics. 8. Ca2+ transients recorded in Indo-1-loaded cells were not augmented by phenylephrine. Diastolic calcium level was decreased. 9. In single skinned cells, the Ca2+ sensitivity of the contractile proteins was increased by a pre-treatment with phenylephrine even when the alpha 1-adrenoceptor-mediated alkalinizing effect had been prevented by EIPA. 10. These results lead us to propose that the alpha 1-adrenergic-induced positive inotropic response of heart muscle could result from an increased sensitivity of the myofilaments to Ca2+ ions. This alpha 1-adrenoceptor-mediated Ca2+ sensitization could result both from an intracellular alkalinization and from a direct effect on contractile proteins.

Full text

PDF
279

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Belles B., Malécot C. O., Hescheler J., Trautwein W. "Run-down" of the Ca current during long whole-cell recordings in guinea pig heart cells: role of phosphorylation and intracellular calcium. Pflugers Arch. 1988 Apr;411(4):353–360. doi: 10.1007/BF00587713. [DOI] [PubMed] [Google Scholar]
  2. Berridge M. J. Inositol trisphosphate and diacylglycerol as second messengers. Biochem J. 1984 Jun 1;220(2):345–360. doi: 10.1042/bj2200345. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Brückner R., Scholz H. Effects of alpha-adrenoceptor stimulation with phenylephrine in the presence of propranolol on force of contraction, slow inward current and cyclic AMP content in the bovine heart. Br J Pharmacol. 1984 May;82(1):223–232. doi: 10.1111/j.1476-5381.1984.tb16462.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Capogrossi M. C., Kaku T., Filburn C. R., Pelto D. J., Hansford R. G., Spurgeon H. A., Lakatta E. G. Phorbol ester and dioctanoylglycerol stimulate membrane association of protein kinase C and have a negative inotropic effect mediated by changes in cytosolic Ca2+ in adult rat cardiac myocytes. Circ Res. 1990 Apr;66(4):1143–1155. doi: 10.1161/01.res.66.4.1143. [DOI] [PubMed] [Google Scholar]
  5. Crompton M., Kessar P., Al-Nasser I. The alpha-adrenergic-mediated activation of the cardiac mitochondrial Ca2+ uniporter and its role in the control of intramitochondrial Ca2+ in vivo. Biochem J. 1983 Nov 15;216(2):333–342. doi: 10.1042/bj2160333. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Endoh M., Blinks J. R. Actions of sympathomimetic amines on the Ca2+ transients and contractions of rabbit myocardium: reciprocal changes in myofibrillar responsiveness to Ca2+ mediated through alpha- and beta-adrenoceptors. Circ Res. 1988 Feb;62(2):247–265. doi: 10.1161/01.res.62.2.247. [DOI] [PubMed] [Google Scholar]
  7. Endoh M., Hiramoto T., Ishihata A., Takanashi M., Inui J. Myocardial alpha 1-adrenoceptors mediate positive inotropic effect and changes in phosphatidylinositol metabolism. Species differences in receptor distribution and the intracellular coupling process in mammalian ventricular myocardium. Circ Res. 1991 May;68(5):1179–1190. doi: 10.1161/01.res.68.5.1179. [DOI] [PubMed] [Google Scholar]
  8. Fabiato A., Fabiato F. Effects of pH on the myofilaments and the sarcoplasmic reticulum of skinned cells from cardiace and skeletal muscles. J Physiol. 1978 Mar;276:233–255. doi: 10.1113/jphysiol.1978.sp012231. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Fedida D., Shimoni Y., Giles W. R. A novel effect of norepinephrine on cardiac cells is mediated by alpha 1-adrenoceptors. Am J Physiol. 1989 May;256(5 Pt 2):H1500–H1504. doi: 10.1152/ajpheart.1989.256.5.H1500. [DOI] [PubMed] [Google Scholar]
  10. Frelin C., Vigne P., Ladoux A., Lazdunski M. The regulation of the intracellular pH in cells from vertebrates. Eur J Biochem. 1988 May 16;174(1):3–14. doi: 10.1111/j.1432-1033.1988.tb14055.x. [DOI] [PubMed] [Google Scholar]
  11. Hamill O. P., Marty A., Neher E., Sakmann B., Sigworth F. J. Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflugers Arch. 1981 Aug;391(2):85–100. doi: 10.1007/BF00656997. [DOI] [PubMed] [Google Scholar]
  12. Hartmann H. A., Mazzocca N. J., Kleiman R. B., Houser S. R. Effects of phenylephrine on calcium current and contractility of feline ventricular myocytes. Am J Physiol. 1988 Nov;255(5 Pt 2):H1173–H1180. doi: 10.1152/ajpheart.1988.255.5.H1173. [DOI] [PubMed] [Google Scholar]
  13. Hescheler J., Nawrath H., Tang M., Trautwein W. Adrenoceptor-mediated changes of excitation and contraction in ventricular heart muscle from guinea-pigs and rabbits. J Physiol. 1988 Mar;397:657–670. doi: 10.1113/jphysiol.1988.sp017024. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Jahnel U., Nawrath H., Carmeliet E., Vereecke J. Depolarization-induced influx of sodium in response to phenylephrine in rat atrial heart muscle. J Physiol. 1991 Jan;432:621–637. doi: 10.1113/jphysiol.1991.sp018404. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Kurachi Y. The effects of intracellular protons on the electrical activity of single ventricular cells. Pflugers Arch. 1982 Sep;394(3):264–270. doi: 10.1007/BF00589102. [DOI] [PubMed] [Google Scholar]
  16. Lacerda A. E., Rampe D., Brown A. M. Effects of protein kinase C activators on cardiac Ca2+ channels. Nature. 1988 Sep 15;335(6187):249–251. doi: 10.1038/335249a0. [DOI] [PubMed] [Google Scholar]
  17. Ledda F., Marchetti P., Mugelli A. Studies on the positive inotropic effect of phenylephrine: a comparison with isoprenaline. Br J Pharmacol. 1975 May;54(1):83–90. doi: 10.1111/j.1476-5381.1975.tb07413.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Movsesian M. A., Nishikawa M., Adelstein R. S. Phosphorylation of phospholamban by calcium-activated, phospholipid-dependent protein kinase. Stimulation of cardiac sarcoplasmic reticulum calcium uptake. J Biol Chem. 1984 Jul 10;259(13):8029–8032. [PubMed] [Google Scholar]
  19. Movsesian M. A., Thomas A. P., Selak M., Williamson J. R. Inositol trisphosphate does not release Ca2+ from permeabilized cardiac myocytes and sarcoplasmic reticulum. FEBS Lett. 1985 Jun 17;185(2):328–332. doi: 10.1016/0014-5793(85)80932-7. [DOI] [PubMed] [Google Scholar]
  20. Orchard C. H., Kentish J. C. Effects of changes of pH on the contractile function of cardiac muscle. Am J Physiol. 1990 Jun;258(6 Pt 1):C967–C981. doi: 10.1152/ajpcell.1990.258.6.C967. [DOI] [PubMed] [Google Scholar]
  21. Otani H., Otani H., Das D. K. Alpha 1-adrenoceptor-mediated phosphoinositide breakdown and inotropic response in rat left ventricular papillary muscles. Circ Res. 1988 Jan;62(1):8–17. doi: 10.1161/01.res.62.1.8. [DOI] [PubMed] [Google Scholar]
  22. Otani H., Otani H., Uriu T., Hara M., Inoue M., Omori K., Cragoe E. J., Jr, Inagaki C. Effects of inhibitors of protein kinase C and Na+/H+ exchange on alpha 1-adrenoceptor-mediated inotropic responses in the rat left ventricular papillary muscle. Br J Pharmacol. 1990 Jun;100(2):207–210. doi: 10.1111/j.1476-5381.1990.tb15783.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Philipson K. D., Bersohn M. M., Nishimoto A. Y. Effects of pH on Na+-Ca2+ exchange in canine cardiac sarcolemmal vesicles. Circ Res. 1982 Feb;50(2):287–293. doi: 10.1161/01.res.50.2.287. [DOI] [PubMed] [Google Scholar]
  24. Poggioli J., Sulpice J. C., Vassort G. Inositol phosphate production following alpha 1-adrenergic, muscarinic or electrical stimulation in isolated rat heart. FEBS Lett. 1986 Oct 6;206(2):292–298. doi: 10.1016/0014-5793(86)80999-1. [DOI] [PubMed] [Google Scholar]
  25. Pressler M. L. Phasic changes in intracellular pH during action potentials of sheep Purkinje fibres. Pflugers Arch. 1988 Jan;411(1):69–75. doi: 10.1007/BF00581648. [DOI] [PubMed] [Google Scholar]
  26. Puceat M., Clement O., Lechene P., Pelosin J. M., Ventura-Clapier R., Vassort G. Neurohormonal control of calcium sensitivity of myofilaments in rat single heart cells. Circ Res. 1990 Aug;67(2):517–524. doi: 10.1161/01.res.67.2.517. [DOI] [PubMed] [Google Scholar]
  27. Pucéat M., Clément O., Scamps F., Vassort G. Extracellular ATP-induced acidification leads to cytosolic calcium transient rise in single rat cardiac myocytes. Biochem J. 1991 Feb 15;274(Pt 1):55–62. doi: 10.1042/bj2740055. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Ravens U., Wang X. L., Wettwer E. Alpha adrenoceptor stimulation reduces outward currents in rat ventricular myocytes. J Pharmacol Exp Ther. 1989 Jul;250(1):364–370. [PubMed] [Google Scholar]
  29. Reiter M. Calcium mobilization and cardiac inotropic mechanisms. Pharmacol Rev. 1988 Sep;40(3):189–217. [PubMed] [Google Scholar]
  30. Roos A., Boron W. F. Intracellular pH. Physiol Rev. 1981 Apr;61(2):296–434. doi: 10.1152/physrev.1981.61.2.296. [DOI] [PubMed] [Google Scholar]
  31. Scamps F., Legssyer A., Mayoux E., Vassort G. The mechanism of positive inotropy induced by adenosine triphosphate in rat heart. Circ Res. 1990 Oct;67(4):1007–1016. doi: 10.1161/01.res.67.4.1007. [DOI] [PubMed] [Google Scholar]
  32. Scholz J., Schaefer B., Schmitz W., Scholz H., Steinfath M., Lohse M., Schwabe U., Puurunen J. Alpha-1 adrenoceptor-mediated positive inotropic effect and inositol trisphosphate increase in mammalian heart. J Pharmacol Exp Ther. 1988 Apr;245(1):327–335. [PubMed] [Google Scholar]
  33. Schouten V. J., Morad M. Regulation of Ca2+ current in frog ventricular myocytes by the holding potential, c-AMP and frequency. Pflugers Arch. 1989 Oct;415(1):1–11. doi: 10.1007/BF00373135. [DOI] [PubMed] [Google Scholar]
  34. Schümann H. J., Endoh S., Brodde O. E. The time course of the effects of beta- and alpha-adrenoceptor stimulation by isoprenaline and methoxamine on the contractile force and cAMP level of the isolated rabbit papillary muscle. Naunyn Schmiedebergs Arch Pharmacol. 1975;289(3):291–302. doi: 10.1007/BF00499982. [DOI] [PubMed] [Google Scholar]
  35. Sen L., Liang B. T., Colucci W. S., Smith T. W. Enhanced alpha 1-adrenergic responsiveness in cardiomyopathic hamster cardiac myocytes. Relation to the expression of pertussis toxin-sensitive G protein and alpha 1-adrenergic receptors. Circ Res. 1990 Nov;67(5):1182–1192. doi: 10.1161/01.res.67.5.1182. [DOI] [PubMed] [Google Scholar]
  36. Skomedal T., Osnes J. B., Oye I. Differences between alpha-adrenergic and beta-adrenergic inotropic effects in rat heart papillary muscles. Acta Pharmacol Toxicol (Copenh) 1982 Jan;50(1):1–12. doi: 10.1111/j.1600-0773.1982.tb00932.x. [DOI] [PubMed] [Google Scholar]
  37. Terzic A., Anagnostopoulos T., Vogel S. M. Opposite modulation of ouabain cardiotoxicity by hexamethyleneamiloride and phenylephrine. Naunyn Schmiedebergs Arch Pharmacol. 1991 May;343(5):511–518. doi: 10.1007/BF00169554. [DOI] [PubMed] [Google Scholar]
  38. Terzic A., Vogel S. M. Amiloride-sensitive actions of an alpha-adrenoceptor agonist and ouabain in rat atria. J Mol Cell Cardiol. 1990 Apr;22(4):391–402. doi: 10.1016/0022-2828(90)91475-m. [DOI] [PubMed] [Google Scholar]
  39. Terzic A., Vogel S. M. On the mechanism of the positive inotropic action of the alpha adrenoceptor agonist, phenylephrine, in isolated rat left atria. J Pharmacol Exp Ther. 1991 Apr;257(1):520–529. [PubMed] [Google Scholar]
  40. Vaughan-Jones R. D., Eisner D. A., Lederer W. J. Effects of changes of intracellular pH on contraction in sheep cardiac Purkinje fibers. J Gen Physiol. 1987 Jun;89(6):1015–1032. doi: 10.1085/jgp.89.6.1015. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Vaughan-Jones R. D. Regulation of intracellular pH in cardiac muscle. Ciba Found Symp. 1988;139:23–46. doi: 10.1002/9780470513699.ch3. [DOI] [PubMed] [Google Scholar]
  42. Vigne P., Frelin C., Lazdunski M. The Na+/H+ antiport is activated by serum and phorbol esters in proliferating myoblasts but not in differentiated myotubes. Properties of the activation process. J Biol Chem. 1985 Jul 5;260(13):8008–8013. [PubMed] [Google Scholar]
  43. Vites A. M., Pappano A. Inositol 1,4,5-trisphosphate releases intracellular Ca2+ in permeabilized chick atria. Am J Physiol. 1990 Jun;258(6 Pt 2):H1745–H1752. doi: 10.1152/ajpheart.1990.258.6.H1745. [DOI] [PubMed] [Google Scholar]
  44. Vogel S. M., Terzic A. Alpha-adrenergic regulation of action potentials in isolated rat cardiomyocytes. Eur J Pharmacol. 1989 May 19;164(2):231–239. doi: 10.1016/0014-2999(89)90463-9. [DOI] [PubMed] [Google Scholar]
  45. Wagner J., Brodde O. E. On the presence and distribution of alpha-adrenoceptors in the heart of various mammalian species. Naunyn Schmiedebergs Arch Pharmacol. 1978 May;302(3):239–254. doi: 10.1007/BF00508293. [DOI] [PubMed] [Google Scholar]
  46. Williams R. S., Lefkowitz R. J. Alpha-adrenergic receptors in rat myocardium. Identification by binding of [3H]dihydroergocryptine. Circ Res. 1978 Nov;43(5):721–727. doi: 10.1161/01.res.43.5.721. [DOI] [PubMed] [Google Scholar]
  47. Zaza A., Kline R. P., Rosen M. R. Effects of alpha-adrenergic stimulation on intracellular sodium activity and automaticity in canine Purkinje fibers. Circ Res. 1990 Feb;66(2):416–426. doi: 10.1161/01.res.66.2.416. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Physiology are provided here courtesy of The Physiological Society

RESOURCES