| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Department of Pharmacology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
1. Properties of the pinacidil-sensitive K+ channel in the smooth muscle of the rabbit portal vein were investigated using cell-attached and inside- and outside-out patch clamp techniques. 2. In the cell-attached patch configuration, a K+ channel with a unitary conductance of 150 pS could be recorded when physiological salt solution (PSS) was in the pipette and high-K+ solution was in the bath. Tetraethylammonium (TEA; less than 1 mM) and charybdotoxin (CTX; greater than 50 nM) inhibited the 150 pS K+ channel from the outside of the membrane. This channel was activated by an increase in the concentrations of intracellular Ca2+ but not by pinacidil (less than or equal to 500 microM). 3. In the cell-attached patch configuration, bath application of pinacidil (greater than 3 microM) activated a K+ channel (ATP-sensitive K+ channel) with a unitary conductance of 15 pS and the enhancing action of pinacidil was blocked by glibenclamide. However, in the cell-free patch configuration, pinacidil (100 microM) failed to open the 15 pS K+ channel. With pinacidil in the pipette, the 15 pS K+ channel was completely inactivated within 5 s of the excision of the membrane. Opening of the 15 pS K+ channel also disappeared after saponin treatment (50 micrograms/ml). 4. In the cell-free patch configuration, application of guanosine 5'-diphosphate (GDP; greater than 100 microM) re-activated the inactivated 15 pS K+ channel only when pinacidil was present either in the pipette or bath. GDP increased the mean open time and open probability of the 15 pS K+ channel in a concentration-dependent manner. Simultaneous application of MgCl2 (less than or equal to 1 mM) with GDP did not modify the GDP-induced activation. Neither GDP nor GTP (1 mM) had any effect on the 150 pS K+ channel. 5. Guanosine 5'-triphosphate (GTP; 1 mM) activated the 15 pS K+ channel to a lesser extent that did GDP. Other guanine nucleotides (guanosine 5'-monophosphate, GMP, 1 mM; guanosine 5'-O-(3-thiotriphosphate), GTP gamma S, 100 microM; and guanosine 5'-O-(2-thiodiphosphate), GDP beta S, 1 mM) failed to activate the 15 pS K+ channel. However, GDP beta S, but not GMP or GTP gamma S, inhibited this channel when it was activated by 1 mM-GDP. 6. In the presence of pinacidil, adenosine 5'-triphosphate (ATP; greater than or equal to 10 microM) inhibited the ATP-sensitive K+ channel when it was activated by 1 mM-GDP.(ABSTRACT TRUNCATED AT 400 WORDS)
This article has been cited by other articles:
|
|
 |
|
  H. Hibino and Y. Kurachi A New Insight Into the Pathogenesis of Coronary Vasospasm Circ. Res., March 17, 2006; 98(5): 579 - 581. [Full Text] [PDF]
|
|
|
|
 |
|
 G. Tang, L. Wu, W. Liang, and R. Wang Direct Stimulation of KATP Channels by Exogenous and Endogenous Hydrogen Sulfide in Vascular Smooth Muscle Cells Mol. Pharmacol., December 1, 2005; 68(6): 1757 - 1764. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Nakayama, S. Ohya, H.-N. Liu, T. Watanabe, S. Furuzono, J. Wang, Y. Nishizawa, M. Aoyama, N. Murase, T. Matsubara, et al. Sulphonylurea receptors differently modulate ICC pacemaker Ca2+ activity and smooth muscle contractility J. Cell Sci., September 15, 2005; 118(18): 4163 - 4173. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. Milesi, J. Raingo, A. Rebolledo, and A. O. G. de Gende Potassium Channels in Human Umbilical Artery Cells Reproductive Sciences, September 1, 2003; 10(6): 339 - 346. [Abstract] [PDF]
|
|
|
|
|
|
M. Suzuki, R. A. Li, T. Miki, H. Uemura, N. Sakamoto, Y. Ohmoto-Sekine, M. Tamagawa, T. Ogura, S. Seino, E. Marban, et al. Functional Roles of Cardiac and Vascular ATP-Sensitive Potassium Channels Clarified by Kir6.2-Knockout Mice Circ. Res., March 30, 2001; 88(6): 570 - 577. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. C. Cole, T. Malcolm, M. P. Walsh, and P. E. Light Inhibition by Protein Kinase C of the KNDP Subtype of Vascular Smooth Muscle ATP-Sensitive Potassium Channel Circ. Res., July 21, 2000; 87(2): 112 - 117. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
U. Russ, A. Hambrock, F. Artunc, C. Löffler-Walz, Y. Horio, Y. Kurachi, and U. Quast Coexpression with the Inward Rectifier K+ Channel Kir6.1 Increases the Affinity of the Vascular Sulfonylurea Receptor SUR2B for Glibenclamide Mol. Pharmacol., November 1, 1999; 56(5): 955 - 961. [Abstract] [Full Text]
|
|
|
|
 |
|
 S. K Mishra and P. I Aaronson A role for a glibenclamide-sensitive, relatively ATP-insensitive K+ current in regulating membrane potential and current in rat aorta Cardiovasc Res, November 1, 1999; 44(2): 429 - 435. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Ledoux, D. Chartier, and N. Leblanc Inhibitors of Calmodulin-Dependent Protein Kinase Are Nonspecific Blockers of Voltage-Dependent K+ Channels in Vascular Myocytes J. Pharmacol. Exp. Ther., September 1, 1999; 290(3): 1165 - 1174. [Abstract] [Full Text]
|
|
|
|
|
|
A. Guia, X. Wan, M. Courtemanche, and N. Leblanc Local Ca2+ Entry Through L-Type Ca2+ Channels Activates Ca2+-Dependent K+ Channels in Rabbit Coronary Myocytes Circ. Res., May 14, 1999; 84(9): 1032 - 1042. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. A. Chutkow, J. C. Makielski, D. J. Nelson, C. F. Burant, and Z. Fan Alternative Splicing of sur2 Exon 17 Regulates Nucleotide Sensitivity of the ATP-sensitive Potassium Channel J. Biol. Chem., May 7, 1999; 274(19): 13656 - 13665. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S.-M. Huang, S. Nakayama, S. Iino, and T. Tomita Voltage sensitivity of slow wave frequency in isolated circular muscle strips from guinea pig gastric antrum Am J Physiol Gastrointest Liver Physiol, February 1, 1999; 276(2): G518 - G528. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. KURIYAMA, K. KITAMURA, T. ITOH, and R. INOUE Physiological Features of Visceral Smooth Muscle Cells, With Special Reference to Receptors and Ion Channels Physiol Rev, July 1, 1998; 78(3): 811 - 920. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R. López-López, M. T. Pérez-García, E. Canet, and C. Gonzalez Effects of Almitrine Bismesylate on the Ionic Currents of Chemoreceptor Cells from the Carotid Body Mol. Pharmacol., February 1, 1998; 53(2): 330 - 339. [Abstract] [Full Text]
|
|
|
|
|
|
L. AGUILAR-BRYAN, J. P. CLEMENT IV, G. GONZALEZ, K. KUNJILWAR, A. BABENKO, and J. BRYAN Toward Understanding the Assembly and Structure of KATP Channels Physiol Rev, January 1, 1998; 78(1): 227 - 245. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Yokoshiki, M. Sunagawa, T. Seki, and N. Sperelakis ATP-sensitive K+ channels in pancreatic, cardiac, and vascular smooth muscle cells Am J Physiol Cell Physiol, January 1, 1998; 274(1): C25 - C37. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Jiang and G. G. Haddad Modulation of K+ Channels by Intracellular ATP in Human Neocortical Neurons J Neurophysiol, January 1, 1997; 77(1): 93 - 102. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Teramoto and A. F. Brading Nicorandil Activates Glibenclamide-Sensitive K+ Channels in Smooth Muscle Cells of Pig Proximal Urethra J. Pharmacol. Exp. Ther., January 1, 1997; 280(1): 483 - 491. [Abstract] [Full Text]
|
|
|
|
|
|
S. Isomoto, C. Kondo, M. Yamada, S. Matsumoto, Y. Horio, Y. Matsuzawa, and Y. Kurachi A Novel Sulfonylurea Receptor Forms with BIR (Kir6.2) a Smooth Muscle Type ATP-sensitive K+ Channel J. Biol. Chem., October 4, 1996; 271(40): 24321 - 24324. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Tateishi and J. E. Faber ATP-Sensitive K+ Channels Mediate {alpha}2D-Adrenergic Receptor Contraction of Arteriolar Smooth Muscle and Reversal of Contraction by Hypoxia Circ. Res., January 1, 1995; 76(1): 53 - 63. [Abstract] [Full Text]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
