| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas, Dallas 75231; 2 Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas 75235; and 3 Division of Cardiology, The Pennsylvania State University College of Medicine, The Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
Inhibition of cutaneous nitric oxide (NO) synthase reduces the magnitude of cutaneous vasodilation during whole body heating in humans. However, this observation is insufficient to conclude that NO concentration increases in the skin during a heat stress. This study was designed to test the hypothesis that whole body heating increases cutaneous interstitial NO concentration. This was accomplished by placing 2 microdialysis membranes in the forearm dermal space of 12 subjects. Both membranes were perfused with lactated Ringer solutions at a rate of 2 µl/min. In both normothermia and during whole body heating via a water perfused suit, dialysate from these membranes were obtained and analyzed for NO using the chemiluminescence technique. In six of these subjects, after the heat stress, the membranes were perfused with a 1 M solution of acetylcholine to stimulate NO release. Dialysate from these trials was also assayed to quantify cutaneous interstitial NO concentration. Whole body heating increased skin temperature from 34.6 ± 0.2 to 38.8 ± 0.2°C (P < 0.05), which increased sublingual temperature (36.4 ± 0.1 to 37.6 ± 0.1°C; P < 0.05), heart rate (63 ± 5 to 93 ± 5 beats/min; P < 0.05), and skin blood flow over the membranes (21 ± 4 to 88 ± 10 perfusion units; P < 0.05). NO concentration in the dialysate did not increase significantly during of the heat stress (7.6 ± 0.7 to 8.6 ± 0.8 µM; P > 0.05). After the heat stress, administration of acetylcholine in the perfusate significantly increased skin blood flow (128 ± 6 perfusion units) relative to both normothermic and heat stress values and significantly increased NO concentration in the dialysate (15.8 ± 2.4 µM). These data suggest that whole body heating does not increase cutaneous interstitial NO concentration in forearm skin. Rather, NO may serve in a permissive role in facilitating the effects of an unknown neurotransmitter, leading to cutaneous vasodilation during a heat stress.
active cutaneous vasodilation; skin blood flow; thermoregulation; acetylcholine
This article has been cited by other articles:
|
|
 |
|
  D. A. Low, M. Shibasaki, S. L. Davis, D. M. Keller, and C. G. Crandall Does local heating-induced nitric oxide production attenuate vasoconstrictor responsiveness to lower body negative pressure in human skin? J Appl Physiol, May 1, 2007; 102(5): 1839 - 1843. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. L. Kellogg Jr In vivo mechanisms of cutaneous vasodilation and vasoconstriction in humans during thermoregulatory challenges J Appl Physiol, May 1, 2006; 100(5): 1709 - 1718. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. J. Green, A. J. Maiorana, J. H. J. Siong, V. Burke, M. Erickson, C. T. Minson, W. Bilsborough, and G. O'Driscoll Impaired skin blood flow response to environmental heating in chronic heart failure Eur. Heart J., February 1, 2006; 27(3): 338 - 343. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. R. Colberg, H. K. Parson, D. R. Holton, T. Nunnold, and A. I. Vinik Cutaneous Blood Flow in Type 2 Diabetic Individuals After an Acute Bout of Maximal Exercise Diabetes Care, June 1, 2003; 26(6): 1883 - 1888. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. L. Kellogg Jr., J. L. Zhao, C. Friel, and L. J. Roman Nitric oxide concentration increases in the cutaneous interstitial space during heat stress in humans J Appl Physiol, May 1, 2003; 94(5): 1971 - 1977. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. A. Holowatz, B. L. Houghton, B. J. Wong, B. W. Wilkins, A. W. Harding, W. L. Kenney, and C. T. Minson Nitric oxide and attenuated reflex cutaneous vasodilation in aged skin Am J Physiol Heart Circ Physiol, May 1, 2003; 284(5): H1662 - H1667. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Shibasaki, T. E. Wilson, J. Cui, and C. G. Crandall Acetylcholine released from cholinergic nerves contributes to cutaneous vasodilation during heat stress J Appl Physiol, December 1, 2002; 93(6): 1947 - 1951. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. T. Minson, L. A. Holowatz, B. J. Wong, W. L. Kenney, and B. W. Wilkins Decreased nitric oxide- and axon reflex-mediated cutaneous vasodilation with age during local heating J Appl Physiol, November 1, 2002; 93(5): 1644 - 1649. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
