Vascular actions of C-type natriuretic peptide in isolated porcine coronary arteries and coronary vascular smooth muscle cells

Biochem Biophys Res Commun. 1994 Nov 30;205(1):765-71. doi: 10.1006/bbrc.1994.2731.

Abstract

C-type natriuretic (CNP) caused concentration-dependent relaxations in porcine coronary arteries with a maximal relaxation (10(-6)M) of 46%. Relaxations to CNP in isolated coronary arteries were significantly attenuated with potassium channel antagonists charybdotoxin (10(-7)M) and glibenclamide (10(-7)M). Membrane potential and K+ currents were measured in enzymatically dissociated smooth muscle cells from porcine coronary arteries with patch-clamp techniques in a whole-cell mode (n = 5). CNP caused K+ channel activation and membrane hyperpolarization in a dose-dependent manner. This hyperpolarization was markedly suppressed by the potassium channel inhibitor tetraethylammonium (TEA, 5 mM). These results demonstrate that CNP relaxes porcine coronary arterial smooth muscle by hyperpolarization of vascular smooth muscle through potassium channel stimulation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Arteries / drug effects*
  • Arteries / physiology
  • Atrial Natriuretic Factor / pharmacology*
  • Coronary Vessels / drug effects*
  • Coronary Vessels / physiology
  • In Vitro Techniques
  • Membrane Potentials / drug effects
  • Muscle Relaxation / drug effects
  • Muscle, Smooth, Vascular / cytology
  • Muscle, Smooth, Vascular / drug effects*
  • Muscle, Smooth, Vascular / physiology
  • Natriuretic Peptide, C-Type
  • Potassium Channels / drug effects
  • Potassium Channels / physiology
  • Proteins / pharmacology*
  • Swine

Substances

  • Potassium Channels
  • Proteins
  • Natriuretic Peptide, C-Type
  • Atrial Natriuretic Factor