Abstract
C-type natriuretic (CNP) caused concentration-dependent relaxations in porcine coronary arteries with a maximal relaxation (10-6M) of 46%. Relaxations to CNP in isolated coronary arteries were significantly attenuated with potassium channel antagonists charybdotoxin (10-7M) and glibenclamide (10-7M). 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.
Original language | English (US) |
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Pages (from-to) | 765-771 |
Number of pages | 7 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 205 |
Issue number | 1 |
DOIs | |
State | Published - Nov 30 1994 |
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Molecular Biology
- Cell Biology