| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
AJP - Heart and Circulatory Physiology, Vol 271, Issue 2 696-H705, Copyright © 1996 by American Physiological Society
ARTICLES |
B. E. Robertson, A. D. Bonev and M. T. Nelson
Department of Pharmacology, University of Vermont, Colchester 05446, USA.
Inward rectifier K+ channels have been implicated in the control of membrane potential and external K(+)-induced dilations of small coronary arteries. To identify and characterize inward rectifier K+ currents in coronary artery smooth muscle, whole cell K+ currents in smooth muscle cells enzymatically isolated from rat coronary (septal) arteries (diameters, 100-150 microns) were measured in the conventional and perforated configurations of the patch-clamp technique. Ba(2+)-sensitive, whole cell K+ current-voltage relationships exhibited inward rectification. Blockers of Ca(2+)-activated K+ channels (1 mM tetraethylammonium ion), ATP-sensitive K+ channels (10 microM glibenclamide), and voltage-dependent K+ channels (1 mM 4-aminopyridine) in smooth muscle did not affect inward rectifier K+ currents. The nonselective K+ channel inhibitor phencyclidine (100 microM) reduced inward rectifier K+ currents by approximately 50%. External Ba2+ reduced inward currents, with membrane potential hyperpolarization increasing inhibition. The half-inhibition constant for Ba2+ was 2.1 microM at -60 mV, decreasing e-fold for a 25-mV hyperpolarization. External Cs+ also blocked inward rectifier K+ currents, with the half-inhibition constant for Cs+ of 2.9 mM at -60 mV. External Ca2+ and Mg2+ reduced inward rectifier K+ currents. At -60 mV, Ca2+ and Mg2+ (1 mM) reduced inward currents by 33 and 21%, respectively. Inward rectification was not affected by dialysis of the cell's interior with a nominally Ca(2+)- and Mg(2+)-free solution. These findings indicate that inward rectifier K+ channels exist in coronary artery smooth muscle and that Ba2+ may be a useful probe for the functional role of inward rectifier K+ channels in coronary arteries.
This article has been cited by other articles:
|
|
 |
|
  P. D. Smith, S. E. Brett, K. D. Luykenaar, S. L. Sandow, S. P. Marrelli, E. J. Vigmond, and D. G. Welsh KIR channels function as electrical amplifiers in rat vascular smooth muscle J. Physiol., February 15, 2008; 586(4): 1147 - 1160. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Cao, W. Lee-Kwon, K. Payne, A. Edwards, and T. L. Pallone Descending vasa recta endothelia express inward rectifier potassium channels Am J Physiol Renal Physiol, October 1, 2007; 293(4): F1248 - F1255. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Zhang, R. Berra-Romani, M. J. Sinnegger-Brauns, J. Striessnig, M. P. Blaustein, and D. R. Matteson Role of Cav1.2 L-type Ca2+ channels in vascular tone: effects of nifedipine and Mg2+ Am J Physiol Heart Circ Physiol, January 1, 2007; 292(1): H415 - H425. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. C. Jantzi, S. E. Brett, W. F. Jackson, R. Corteling, E. J. Vigmond, and D. G. Welsh Inward rectifying potassium channels facilitate cell-to-cell communication in hamster retractor muscle feed arteries Am J Physiol Heart Circ Physiol, September 1, 2006; 291(3): H1319 - H1328. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Qamirani, H. M. Razavi, X. Wu, M. J. Davis, L. Kuo, and T. W. Hein Sodium azide dilates coronary arterioles via activation of inward rectifier K+ channels and Na+-K+-ATPase Am J Physiol Heart Circ Physiol, April 1, 2006; 290(4): H1617 - H1623. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. J. Haddy, P. M. Vanhoutte, and M. Feletou Role of potassium in regulating blood flow and blood pressure Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2006; 290(3): R546 - R552. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Radaelli, P. Castiglioni, M. Centola, F. Cesana, G. Balestri, A. U. Ferrari, and M. Di Rienzo Adrenergic origin of very low-frequency blood pressure oscillations in the unanesthetized rat Am J Physiol Heart Circ Physiol, January 1, 2006; 290(1): H357 - H364. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Y. Kim, G. H. Liang, J. A. Kim, S. H. Park, J. S. Hah, and S. H. Suh Contribution of Na+-K+ pump and KIR currents to extracellular pH-dependent changes of contractility in rat superior mesenteric artery Am J Physiol Heart Circ Physiol, August 1, 2005; 289(2): H792 - H800. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Leichtle, U. Rauch, M. Albinus, P. Benohr, H. Kalbacher, A. F Mack, R. W Veh, U. Quast, and U. Russ Electrophysiological and molecular characterization of the inward rectifier in juxtaglomerular cells from rat kidney J. Physiol., October 15, 2004; 560(2): 365 - 376. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. S. Thorneloe and M. T. Nelson Properties of a tonically active, sodium-permeable current in mouse urinary bladder smooth muscle Am J Physiol Cell Physiol, June 1, 2004; 286(6): C1246 - C1257. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. D. Luykenaar, S. E. Brett, B. N. Wu, W. B. Wiehler, and D. G. Welsh Pyrimidine nucleotides suppress KDR currents and depolarize rat cerebral arteries by activating Rho kinase Am J Physiol Heart Circ Physiol, March 1, 2004; 286(3): H1088 - H1100. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Karkanis, S. Li, J. G. Pickering, and S. M. Sims Plasticity of KIR channels in human smooth muscle cells from internal thoracic artery Am J Physiol Heart Circ Physiol, June 1, 2003; 284(6): H2325 - H2334. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Oonuma, K. Iwasawa, H. Iida, T. Nagata, H. Imuta, Y. Morita, K. Yamamoto, R. Nagai, M. Omata, and T. Nakajima Inward Rectifier K+ Current in Human Bronchial Smooth Muscle Cells . Inhibition with Antisense Oligonucleotides Targeted to Kir2.1 mRNA Am. J. Respir. Cell Mol. Biol., March 1, 2002; 26(3): 371 - 379. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Llobet, X. Gasull, J. Pales, E. Marti, and A. Gual Identification of Kir2.1 Channel Activity in Cultured Trabecular Meshwork Cells Invest. Ophthalmol. Vis. Sci., September 1, 2001; 42(10): 2371 - 2379. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. G. Welsh and J. E. Brayden Mechanisms of coronary artery depolarization by uridine triphosphate Am J Physiol Heart Circ Physiol, June 1, 2001; 280(6): H2545 - H2553. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Chilton and R. Loutzenhiser Functional Evidence for an Inward Rectifier Potassium Current in Rat Renal Afferent Arterioles Circ. Res., February 2, 2001; 88(2): 152 - 158. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Ji, A. M. F. Salapatek, and N. E. Diamant Inwardly rectifying K+ channels in esophageal smooth muscle Am J Physiol Gastrointest Liver Physiol, November 1, 2000; 279(5): G951 - G960. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. H. Jaggar and M. T. Nelson Differential regulation of Ca2+ sparks and Ca2+ waves by UTP in rat cerebral artery smooth muscle cells Am J Physiol Cell Physiol, November 1, 2000; 279(5): C1528 - C1539. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T.-S. Nguyen, H. R. Winn, and D. Janigro ATP-sensitive potassium channels may participate in the coupling of neuronal activity and cerebrovascular tone Am J Physiol Heart Circ Physiol, March 1, 2000; 278(3): H878 - H885. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. F. Jackson Ion Channels and Vascular Tone Hypertension, January 1, 2000; 35(1): 173 - 178. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. A. Porter, A. D. Bonev, H. J. Knot, T. J. Heppner, A. S. Stevenson, T. Kleppisch, W. J. Lederer, and M. T. Nelson Frequency modulation of Ca2+ sparks is involved in regulation of arterial diameter by cyclic nucleotides Am J Physiol Cell Physiol, May 1, 1998; 274(5): C1346 - C1355. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. D. Bonev, J. H. Jaggar, M. Rubart, and M. T. Nelson Activators of protein kinase C decrease Ca2+ spark frequency in smooth muscle cells from cerebral arteries Am J Physiol Cell Physiol, December 1, 1997; 273(6): C2090 - C2095. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
