| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Articles in PresS, published online ahead of print August 9, 2002
Am J Physiol Lung Cell Mol Physiol, 10.1152/ajplung.00104.2002
Submitted on April 17, 2002
Accepted on July 13, 2002
1 Staff Anesthesiologist, Justus-Liebig-University, Giessen, Germany
2 Research Associate, VA Medical Center, Minneapolis, USA
3 Scientist, VA Medical Center, Minneapolis, USA
4 Chief of Cardiology, VA Medical Center, Minneapolis, USA
* To whom correspondence should be addressed. E-mail: weirx002{at}tc.umn.edu.
Many studies indicate that hypoxic inhibition of some potassium channels in the membrane of the pulmonary arterial smooth muscle cells (PASMCs) plays a part in initiating hypoxic pulmonary vasoconstriction. The sensitivity of the potassium current (Ik), resting membrane potential (Em) and intracellular [Ca2+] ([Ca2+]i) of PASMCs to different levels of hypoxia in these cells has not been fully explored. Reducing pO2 levels gradually inhibited steady-state Ik of rat resistance PASMCs and depolarized the cell membrane. The block of Ik by hypoxia was voltage-dependent, in that low oxygen tensions (3% and 0% O2) inhibited Ik more at 0mV and -20 mV, than at 50 mV. As expected, the hypoxia-sensitive Ik was also 4-aminopyridinepyridine-sensitive. Fura-2 loaded PASMCs showed a graded increase in [Ca2+]i as pO2 levels declined. This increase was markedly reduced by nifedipine and removal of extracellular Ca2+. We conclude that, as in the carotid body type l cells, PC 12 cells and cortical neurons, increasing severity of hypoxia causes a proportional decrease in Ik, Em and increase of intracellular [Ca2+].
This article has been cited by other articles:
|
|
 |
|
  G. A. Knock, V. A. Snetkov, Y. Shaifta, S. Drndarski, J. P.T. Ward, and P. I. Aaronson Role of src-family kinases in hypoxic vasoconstriction of rat pulmonary artery Cardiovasc Res, December 1, 2008; 80(3): 453 - 462. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. L. Firth, K. H. Yuill, and S. V. Smirnov Mitochondria-dependent regulation of Kv currents in rat pulmonary artery smooth muscle cells Am J Physiol Lung Cell Mol Physiol, July 1, 2008; 295(1): L61 - L70. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Marino, J. L. Beny, A. C. Peyter, R. Bychkov, G. Diaceri, and J. F. Tolsa Perinatal hypoxia triggers alterations in K+ channels of adult pulmonary artery smooth muscle cells Am J Physiol Lung Cell Mol Physiol, November 1, 2007; 293(5): L1171 - L1182. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 O. Platoshyn, E. E. Brevnova, E. D. Burg, Y. Yu, C. V. Remillard, and J. X.-J. Yuan Acute hypoxia selectively inhibits KCNA5 channels in pulmonary artery smooth muscle cells Am J Physiol Cell Physiol, March 1, 2006; 290(3): C907 - C916. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Hinton, L. Mellow, A. J. Halayko, A. Gutsol, and S. Dakshinamurti Hypoxia induces hypersensitivity and hyperreactivity to thromboxane receptor agonist in neonatal pulmonary arterial myocytes Am J Physiol Lung Cell Mol Physiol, February 1, 2006; 290(2): L375 - L384. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. K. Weir, J. Lopez-Barneo, K. J. Buckler, and S. L. Archer Acute Oxygen-Sensing Mechanisms. N. Engl. J. Med., November 10, 2005; 353(19): 2042 - 2055. [Full Text] [PDF]
|
|
|
|
|
|
J. P. T. Ward, T. P. Robertson, and P. I. Aaronson Capacitative calcium entry: a central role in hypoxic pulmonary vasoconstriction? Am J Physiol Lung Cell Mol Physiol, July 1, 2005; 289(1): L2 - L4. [Full Text] [PDF]
|
|
|
|
|
|
J. Wang, L. A. Shimoda, L. Weigand, W. Wang, D. Sun, and J. T. Sylvester Acute hypoxia increases intracellular [Ca2+] in pulmonary arterial smooth muscle by enhancing capacitative Ca2+ entry Am J Physiol Lung Cell Mol Physiol, June 1, 2005; 288(6): L1059 - L1069. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. B. Waypa and P. T. Schumacker Hypoxic pulmonary vasoconstriction: redox events in oxygen sensing J Appl Physiol, January 1, 2005; 98(1): 404 - 414. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R. H. Mauban, C. V. Remillard, and J. X.-J. Yuan Hypoxic pulmonary vasoconstriction: role of ion channels J Appl Physiol, January 1, 2005; 98(1): 415 - 420. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Z. Hong, A. Olschewski, H. L. Reeve, D. P. Nelson, F. Hong, and E. K. Weir Nordexfenfluramine causes more severe pulmonary vasoconstriction than dexfenfluramine Am J Physiol Lung Cell Mol Physiol, March 1, 2004; 286(3): L531 - L538. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Olschewski, Z. Hong, D. A. Peterson, D. P. Nelson, V. A. Porter, and E. K. Weir Opposite effects of redox status on membrane potential, cytosolic calcium, and tone in pulmonary arteries and ductus arteriosus Am J Physiol Lung Cell Mol Physiol, January 1, 2004; 286(1): L15 - L22. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
