Skip to main content
British Journal of Pharmacology logoLink to British Journal of Pharmacology
. 1995 May;115(1):198–202. doi: 10.1111/j.1476-5381.1995.tb16339.x

Inhibitory action of betaxolol, a beta 1-selective adrenoceptor antagonist, on voltage-dependent calcium channels in guinea-pig artery and vein.

M Setoguchi 1, Y Ohya 1, I Abe 1, M Fujishima 1
PMCID: PMC1908754  PMID: 7647977

Abstract

1. The effects of betaxolol, (+/-)-1-[4-[2-(cyclopropylmethoxy) ethyl] phenoxy]-3-(isopropylamino)-2-propanol hydrochloride, a beta 1-selective adrenoceptor antagonist, on voltage-dependent Ca2+ channels were investigated in single smooth muscle cells from guinea-pig mesenteric artery and portal vein using a whole-cell variant of the patch-clamp technique. Ca2+ channel currents were recorded with bath solutions contained 10 mM Ba2+ for arterial cells and 2 mM Ca2+ for venous cells. 2. Betaxolol inhibited Ca2+ channel currents dose-dependently in both mesenteric artery cells and portal vein cells. The two isomers, (+)-betaxolol and (-)-betaxolol (relative beta-antagonistic efficacies of 0.1 and 1, respectively), had similar potencies for inhibiting Ca2+ channel currents in portal vein cells. Propranolol did not inhibit the currents. Thus the inhibitory action of betaxolol on Ca2+ channel currents was independent of the beta-adrenoceptor. 3. The inhibitory action of betaxolol on Ca2+ channel currents was compared with that of diltiazem and of nifedipine in mesenteric artery cells. The current inhibition depended on the stimulation frequency with all drugs (use-dependent block). All drugs also accelerated the current decay and shifted the voltage-dependent inactivation curve in a negative direction. 4. In conclusion, betaxolol inhibited Ca2+ channel currents in vascular smooth muscle cells. The mode of inhibitory action was similar to that of diltiazem and nifedipine. Our results suggest that betaxolol is a unique beta-adrenoceptor antagonist that has a direct inhibitory action on voltage-dependent Ca2+ channels in vascular smooth muscle cells.

Full text

PDF
198

Selected References

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

  1. Bean B. P. Nitrendipine block of cardiac calcium channels: high-affinity binding to the inactivated state. Proc Natl Acad Sci U S A. 1984 Oct;81(20):6388–6392. doi: 10.1073/pnas.81.20.6388. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Beresford R., Heel R. C. Betaxolol. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in hypertension. Drugs. 1986 Jan;31(1):6–28. doi: 10.2165/00003495-198631010-00002. [DOI] [PubMed] [Google Scholar]
  3. Bessho H., Suzuki J., Narimatsu A., Tobe A. [Antihypertensive effect of betaxolol, a cardioselective beta-adrenoceptor antagonist, in experimental hypertensive rats]. Nihon Yakurigaku Zasshi. 1990 Jun;95(6):347–354. doi: 10.1254/fpj.95.6_347. [DOI] [PubMed] [Google Scholar]
  4. Bessho H., Suzuki J., Tobe A. Vascular effects of betaxolol, a cardioselective beta-adrenoceptor antagonist, in isolated rat arteries. Jpn J Pharmacol. 1991 Mar;55(3):351–358. doi: 10.1254/jjp.55.351. [DOI] [PubMed] [Google Scholar]
  5. 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]
  6. Kuga T., Sadoshima J., Tomoike H., Kanaide H., Akaike N., Nakamura M. Actions of Ca2+ antagonists on two types of Ca2+ channels in rat aorta smooth muscle cells in primary culture. Circ Res. 1990 Aug;67(2):469–480. doi: 10.1161/01.res.67.2.469. [DOI] [PubMed] [Google Scholar]
  7. Lee K. S., Tsien R. W. Mechanism of calcium channel blockade by verapamil, D600, diltiazem and nitrendipine in single dialysed heart cells. Nature. 1983 Apr 28;302(5911):790–794. doi: 10.1038/302790a0. [DOI] [PubMed] [Google Scholar]
  8. Mason R. P., Rhodes D. G., Herbette L. G. Reevaluating equilibrium and kinetic binding parameters for lipophilic drugs based on a structural model for drug interaction with biological membranes. J Med Chem. 1991 Mar;34(3):869–877. doi: 10.1021/jm00107a001. [DOI] [PubMed] [Google Scholar]
  9. Ohya Y., Abe I., Fujii K., Takata Y., Fujishima M. Voltage-dependent Ca2+ channels in resistance arteries from spontaneously hypertensive rats. Circ Res. 1993 Dec;73(6):1090–1099. doi: 10.1161/01.res.73.6.1090. [DOI] [PubMed] [Google Scholar]
  10. Ohya Y., Sperelakis N. ATP regulation of the slow calcium channels in vascular smooth muscle cells of guinea pig mesenteric artery. Circ Res. 1989 Jan;64(1):145–154. doi: 10.1161/01.res.64.1.145. [DOI] [PubMed] [Google Scholar]
  11. Sanguinetti M. C., Kass R. S. Voltage-dependent block of calcium channel current in the calf cardiac Purkinje fiber by dihydropyridine calcium channel antagonists. Circ Res. 1984 Sep;55(3):336–348. doi: 10.1161/01.res.55.3.336. [DOI] [PubMed] [Google Scholar]
  12. Satoh N., Suzuki J., Bessho H., Kitada Y., Narimatsu A., Tobe A. Effects of betaxolol on cardiohemodynamics and coronary circulation in anesthetized dogs: comparison with atenolol and propranolol. Jpn J Pharmacol. 1990 Oct;54(2):113–119. doi: 10.1254/jjp.54.113. [DOI] [PubMed] [Google Scholar]
  13. Terada K., Nakao K., Okabe K., Kitamura K., Kuriyama H. Action of the 1,4-dihydropyridine derivative, KW-3049, on the smooth muscle membrane of the rabbit mesenteric artery. Br J Pharmacol. 1987 Nov;92(3):615–625. doi: 10.1111/j.1476-5381.1987.tb11364.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Warrington S. J., Turner P., Kilborn J. R., Bianchetti G., Morselli P. L. Blood concentrations and pharmacodynamic effects of betaxolol (SL 75212) a new beta-adrenoceptor antagonist after oral and intravenous administration. Br J Clin Pharmacol. 1980 Nov;10(5):449–452. doi: 10.1111/j.1365-2125.1980.tb01787.x. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from British Journal of Pharmacology are provided here courtesy of The British Pharmacological Society

RESOURCES