|
|
||||||||
1 Departments of Physiology, Anesthesiology, and Pharmacology/Toxicology, Medical College of Wisconsin and the Department of Veterans Affairs, Veterans Affairs Medical Center, Milwaukee, Wisconsin 53295; and 2 Department of Chemistry, Polytechnic University, Brooklyn, New York 11201
Pulmonary arterial endothelial cells possess transplasma membrane electron transport (TPMET) systems that transfer intracellular reducing equivalents to extracellular electron acceptors. As one aspect of determining cellular mechanisms involved in one such TPMET system in pulmonary arterial endothelial cells in culture, glycolysis was inhibited by treatment with iodoacetate (IOA) or by replacing the glucose in the cell medium with 2-deoxy-D-glucose (2-DG). TPMET activity was measured as the rate of reduction of the extracellular electron acceptor polymer toluidine blue O polyacrylamide. Intracellular concentrations of NADH, NAD+, NADPH, and NADP+ were determined by high-performance liquid chromatography of KOH cell extracts. IOA decreased TPMET activity to 47% of control activity concomitant with a decrease in the NADH/NAD+ ratio to 34% of the control level, without a significant change in the NADPH/NADP+ ratio. 2-DG decreased TPMET activity to 53% of control and decreased both NADH/NAD+ and NADPH/NADP+ ratios to 51% and 55%, respectively, of control levels. When lactate was included in the medium along with the inhibitors, the effects of IOA and 2-DG on both TPMET activity and the NADPH/NADP+ ratios were prevented. The results suggest that cellular redox status is a determinant of pulmonary arterial endothelial cell TPMET activity, with TPMET activity more highly correlated with the poise of the NADH/NAD+ redox pair.
lung; endothelium; pyridine nucleotides
This article has been cited by other articles:
![]() |
S. H. Audi, M. P. Merker, G. S. Krenz, T. Ahuja, D. L. Roerig, and R. D. Bongard Coenzyme Q1 redox metabolism during passage through the rat pulmonary circulation and the effect of hyperoxia J Appl Physiol, October 1, 2008; 105(4): 1114 - 1126. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Ungvari, C. Parrado-Fernandez, A. Csiszar, and R. de Cabo Mechanisms Underlying Caloric Restriction and Lifespan Regulation: Implications for Vascular Aging Circ. Res., March 14, 2008; 102(5): 519 - 528. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. P. Merker, S. H. Audi, B. J. Lindemer, G. S. Krenz, and R. D. Bongard Role of mitochondrial electron transport complex I in coenzyme Q1 reduction by intact pulmonary arterial endothelial cells and the effect of hyperoxia Am J Physiol Lung Cell Mol Physiol, September 1, 2007; 293(3): L809 - L819. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. P. Merker, S. H. Audi, R. D. Bongard, B. J. Lindemer, and G. S. Krenz Influence of pulmonary arterial endothelial cells on quinone redox status: effect of hyperoxia-induced NAD(P)H:quinone oxidoreductase 1 Am J Physiol Lung Cell Mol Physiol, March 1, 2006; 290(3): L607 - L619. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Tipparaju, N. Saxena, S.-Q. Liu, R. Kumar, and A. Bhatnagar Differential regulation of voltage-gated K+ channels by oxidized and reduced pyridine nucleotide coenzymes Am J Physiol Cell Physiol, February 1, 2005; 288(2): C366 - C376. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. M. May, Z.-c. Qu, and C. E. Cobb Reduction and uptake of methylene blue by human erythrocytes Am J Physiol Cell Physiol, June 1, 2004; 286(6): C1390 - C1398. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. H. Audi, R. D. Bongard, C. A. Dawson, D. Siegel, D. L. Roerig, and M. P. Merker Duroquinone reduction during passage through the pulmonary circulation Am J Physiol Lung Cell Mol Physiol, November 1, 2003; 285(5): L1116 - L1131. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |