Excitation-contraction coupling in ventricular myocytes: Effects of angiotensin II

W. H. Barry, H. Matsui, J. H.B. Bridge, K. W. Spitzer, J. Janicki, B. O'Rourke, G. Kessler-Icekson, M. Morad

Research output: Contribution to journalArticle

Abstract

The effects of the vasoactive peptide angiotensin II (AII) on contractility and excitation-contraction coupling in isolated adult rabbit ventricular myocytes were investigated. In most ventricular myocytes, AII (10-8 M) induced a significant increase in fractional shortening which was not associated with an increase in the calcium transient measured with indo- 1. AII did increase the intracellular pH by approximately 0.2 5 pH units coincident with the positive inotropic effect. Effects of AII on pH and contractility were blocked by inhibitors of Na+/H+ exchange. AII also increased the rate of pHi recovery from intracellular acidosis at pH(i) values above 6.9. AII was shown not to affect the L-type inward calcium current. However, in an occasional cell, AII was observed to cause a slight increase in the calcium transient. We hypothesize that this response may reflect an increase of calcium influx on the sodium calcium exchanger, as a consequence of an increase in subsarcolemmal sodium concentration resulting from enhanced Na+-H+ exchange.

Original languageEnglish (US)
Pages (from-to)31-39
Number of pages9
JournalAdvances in experimental medicine and biology
Volume382
DOIs
StatePublished - Jan 1 1995
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Fingerprint Dive into the research topics of 'Excitation-contraction coupling in ventricular myocytes: Effects of angiotensin II'. Together they form a unique fingerprint.

  • Cite this

    Barry, W. H., Matsui, H., Bridge, J. H. B., Spitzer, K. W., Janicki, J., O'Rourke, B., Kessler-Icekson, G., & Morad, M. (1995). Excitation-contraction coupling in ventricular myocytes: Effects of angiotensin II. Advances in experimental medicine and biology, 382, 31-39. https://doi.org/10.1007/978-1-4615-1893-8_4