| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Pharmacology, College of Medicine, The University of Vermont, Colchester, Vermont 05446; and 2 Krannert Institute of Cardiology, Indiana University Medical School, Indianapolis, Indiana 46202
Local Ca2+ transients ("Ca2+ sparks") caused by the opening of one or the coordinated opening of a number of tightly clustered ryanodine-sensitive Ca2+-release (RyR) channels in the sarcoplasmic reticulum (SR) activate nearby Ca2+-dependent K+ (KCa) channels to cause an outward current [referred to as a "spontaneous transient outward current" (STOC)]. These KCa currents cause membrane potential hyperpolarization of arterial myocytes, which would lead to vasodilation through decreasing Ca2+ entry through voltage-dependent Ca2+ channels. Therefore, modulation of Ca2+ spark frequency should be a means to regulation of KCa channel currents and hence membrane potential. We examined the frequency modulation of Ca2+ sparks and STOCs by activation of protein kinase C (PKC). The PKC activators, phorbol 12-myristate 13-acetate (PMA; 10 nM) and 1,2-dioctanoyl-sn-glycerol (1 µM), decreased Ca2+ spark frequency by 72% and 60%, respectively, and PMA reduced STOC frequency by 83%. PMA also decreased STOC amplitude by 22%, which could be explained by an observed reduction (29%) in KCa channel open probability in the absence of Ca2+ sparks. The reduction in STOC frequency occurred in the presence of an inorganic blocker (Cd2+) of voltage-dependent Ca2+ channels. The reduction in Ca2+ spark frequency did not result from SR Ca2+ depletion, since caffeine-induced Ca2+ transients did not decrease in the presence of PMA. These results suggest that activators of PKC can modulate the frequency of Ca2+ sparks, through an effect on the RyR channel, which would decrease STOC frequency (i.e., KCa channel activity).
calcium-dependent potassium channels; caffeine; ryanodine; thapsigargin
This article has been cited by other articles:
|
|
 |
|
  K. Essin, A. Welling, F. Hofmann, F. C. Luft, M. Gollasch, and S. Moosmang Indirect coupling between Cav1.2 channels and ryanodine receptors to generate Ca2+ sparks in murine arterial smooth muscle cells J. Physiol., October 1, 2007; 584(1): 205 - 219. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. A. Williams and S. M. Sims Calcium sparks activate calcium-dependent Cl current in rat corpus cavernosum smooth muscle cells Am J Physiol Cell Physiol, October 1, 2007; 293(4): C1239 - C1251. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. K. Henderson and K. L. Byron Vasopressin-induced vasoconstriction: two concentration-dependent signaling pathways J Appl Physiol, April 1, 2007; 102(4): 1402 - 1409. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Shakirova, J. Bonnevier, S. Albinsson, M. Adner, B. Rippe, J. Broman, A. Arner, and K. Sward Increased Rho activation and PKC-mediated smooth muscle contractility in the absence of caveolin-1. Am J Physiol Cell Physiol, December 1, 2006; 291(6): C1326 - C1335. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Lamont and W. G. Wier Different roles of ryanodine receptors and inositol (1,4,5)-trisphosphate receptors in adrenergically stimulated contractions of small arteries Am J Physiol Heart Circ Physiol, August 1, 2004; 287(2): H617 - H625. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. H. Korzick, M. H. Laughlin, and D. K. Bowles Alterations in PKC signaling underlie enhanced myogenic tone in exercise-trained porcine coronary resistance arteries J Appl Physiol, April 1, 2004; 96(4): 1425 - 1432. [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]
|
|
|
|
 |
|
 W.-M. Zhang, K.-P. Yip, M.-J. Lin, L. A. Shimoda, W.-H. Li, and J. S. K. Sham ET-1 activates Ca2+ sparks in PASMC: local Ca2+ signaling between inositol trisphosphate and ryanodine receptors Am J Physiol Lung Cell Mol Physiol, September 1, 2003; 285(3): L680 - L690. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. J. Heppner, A. D. Bonev, L. F. Santana, and M. T. Nelson Alkaline pH shifts Ca2+ sparks to Ca2+ waves in smooth muscle cells of pressurized cerebral arteries Am J Physiol Heart Circ Physiol, December 1, 2002; 283(6): H2169 - H2176. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. P. R. Jarajapu and H. J. Knot Role of phospholipase C in development of myogenic tone in rat posterior cerebral arteries Am J Physiol Heart Circ Physiol, December 1, 2002; 283(6): H2234 - H2238. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. V. Remillard, W.-M. Zhang, L. A. Shimoda, and J. S. K. Sham Physiological properties and functions of Ca2+ sparks in rat intrapulmonary arterial smooth muscle cells Am J Physiol Lung Cell Mol Physiol, August 1, 2002; 283(2): L433 - L444. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. J. Knot Calcium Sparks Unleashed in Vascular Smooth Muscle: Lessons From the RyR3 Knockout Mouse Circ. Res., November 23, 2001; 89(11): 941 - 943. [Full Text] [PDF]
|
|
|
|
|
|
O. Bayguinov, B. Hagen, J. L. Kenyon, and K. M. Sanders Coupling strength between localized Ca2+ transients and K+ channels is regulated by protein kinase C Am J Physiol Cell Physiol, November 1, 2001; 281(5): C1512 - C1523. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. M. Sanders Signal Transduction in Smooth Muscle: Invited Review: Mechanisms of calcium handling in smooth muscles J Appl Physiol, September 1, 2001; 91(3): 1438 - 1449. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. H. Jaggar Intravascular pressure regulates local and global Ca2+ signaling in cerebral artery smooth muscle cells Am J Physiol Cell Physiol, August 1, 2001; 281(2): C439 - C448. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. M. Pabelick, G. C. Sieck, and Y. S. Prakash Signal Transduction in Smooth Muscle: Invited Review: Significance of spatial and temporal heterogeneity of calcium transients in smooth muscle J Appl Physiol, July 1, 2001; 91(1): 488 - 496. [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]
|
|
|
|
|
|
J. R. H. Mauban, C. Lamont, C. W. Balke, and W. G. Wier Adrenergic stimulation of rat resistance arteries affects Ca2+ sparks, Ca2+ waves, and Ca2+ oscillations Am J Physiol Heart Circ Physiol, May 1, 2001; 280(5): H2399 - H2405. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. W. Fallet, J. P. Bast, K. Fujiwara, N. Ishii, S. C. Sansom, and P. K. Carmines Influence of Ca2+-activated K+ channels on rat renal arteriolar responses to depolarizing agonists Am J Physiol Renal Physiol, April 1, 2001; 280(4): F583 - F591. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
O. Bayguinov, B. Hagen, and K. M. Sanders Muscarinic stimulation increases basal Ca2+ and inhibits spontaneous Ca2+ transients in murine colonic myocytes Am J Physiol Cell Physiol, March 1, 2001; 280(3): C689 - C700. [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]
|
|
|
|
|
|
O. Bayguinov, B. Hagen, A. D. Bonev, M. T. Nelson, and K. M. Sanders Intracellular calcium events activated by ATP in murine colonic myocytes Am J Physiol Cell Physiol, July 1, 2000; 279(1): C126 - C135. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. H. Jaggar, V. A. Porter, W. J. Lederer, and M. T. Nelson Calcium sparks in smooth muscle Am J Physiol Cell Physiol, February 1, 2000; 278(2): C235 - C256. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Schubert, T. Noack, and V. N. Serebryakov Protein kinase C reduces the KCa current of rat tail artery smooth muscle cells Am J Physiol Cell Physiol, March 1, 1999; 276(3): C648 - C658. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Gollasch, G. C. Wellman, H. J. Knot, J. H. Jaggar, D. H. Damon, A. D. Bonev, and M. T. Nelson Ontogeny of Local Sarcoplasmic Reticulum Ca2+ Signals in Cerebral Arteries : Ca2+ Sparks as Elementary Physiological Events Circ. Res., November 30, 1998; 83(11): 1104 - 1114. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. E. Sieber, R. J. Traystman, P. R. Brown, L. J. Martin, and F. M. Faraci Protein Kinase C Expression and Activity After Global Incomplete Cerebral Ischemia in Dogs • Editorial Comment Stroke, July 1, 1998; 29(7): 1445 - 1453. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. H. Jaggar, A. S. Stevenson, and M. T. Nelson Voltage dependence of Ca2+ sparks in intact cerebral arteries Am J Physiol Cell Physiol, June 1, 1998; 274(6): C1755 - C1761. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. J. Pozo, G. J. Perez, M. T. Nelson, and G. M. Mawe Ca2+ sparks and BK currents in gallbladder myocytes: role in CCK-induced response Am J Physiol Gastrointest Liver Physiol, January 1, 2002; 282(1): G165 - G174. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Lohn, W. Jessner, M. Furstenau, M. Wellner, V. Sorrentino, H. Haller, F. C. Luft, and M. Gollasch Regulation of Calcium Sparks and Spontaneous Transient Outward Currents by RyR3 in Arterial Vascular Smooth Muscle Cells Circ. Res., November 23, 2001; 89(11): 1051 - 1057. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
