| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Kinesiology Department, The Pennsylvania State University, University Park, Pennsylvania, United States
2 Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
3 Kinesiology Department, Pennsylvania State University, University Park, Pennsylvania, United States; Intercollege Graduate Degree Program in Physiology, The Pennsylvania State University, University Park, Pennsylvania, United States
* To whom correspondence should be addressed. E-mail: cthomp44{at}jhmi.edu.
Cutaneous vasoconstriction (VC) is the initial thermoregulatory response to cold exposure and can be elicited through either whole-body or localized skin cooling. However, the mechanisms governing local cold-induced VC are not well-understood. We tested the hypothesis that Rho kinase participates in local cold-induced cutaneous VC. In 7 men and women (20-27 years), up to four ventral forearm skin sites were instrumented with intradermal microdialysis fibers for localized drug delivery during cooling. Skin blood flow was monitored at each site with laser Doppler flowmetry (LDF) while local skin temperature was decreased and maintained at 24°C for 40 minutes. Cutaneous vascular conductance (CVC; LDF/mean arterial pressure) was expressed as percentage change from 34°C baseline (%
CVCbase). During the first 5 minutes of cooling, CVC decreased at control sites (lactated Ringers) to -45±6% (p<0.001), increased at adrenoceptor-antagonized sites (yohimbine+propranolol) to 15±14% (p=0.002), and remained unchanged at both Rho kinase-inhibited (fasudil) and adrenoceptor-antagonized+Rho kinase-inhibited sites (yohimbine+propranolol+fasudil) (-9±1%, p=0.4 and -6±2%, p=0.4, respectively). During the last 5 minutes of cooling, CVC further decreased at all sites compared to baseline values (control:-77±4%, p<0.001; adrenoceptor-antagonized: -61±3%, p<0.001; Rho kinase-inhibited: -34±7, p<0.001; and adrenoceptor-antagonized+Rho kinase-inhibited: -35±3%, p<0.001). Rho kinase-inhibited and combined treatment sites were significantly attenuated compared to both adrenoceptor-antagonized (p<0.01) and control sites (p<0.0001). Rho kinase mediates both early- and late-phase cold-induced VC, supporting in vitro findings and providing a putative mechanism through which both adrenergic and non-adrenergic cold-induced VC occurs in an in vivo human thermoregulatory model.
This article has been cited by other articles:
|
|
 |
|
  J. A. Lang, J. D. Jennings, L. A. Holowatz, and W. L. Kenney Reflex vasoconstriction in aged human skin increasingly relies on Rho kinase-dependent mechanisms during whole body cooling Am J Physiol Heart Circ Physiol, November 1, 2009; 297(5): H1792 - H1797. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. E. Wingo, D. A. Low, D. M. Keller, R. M. Brothers, M. Shibasaki, and C. G. Crandall Effect of elevated local temperature on cutaneous vasoconstrictor responsiveness in humans J Appl Physiol, February 1, 2009; 106(2): 571 - 575. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. J. Hodges, W. A. Kosiba, K. Zhao, and J. M. Johnson The involvement of heating rate and vasoconstrictor nerves in the cutaneous vasodilator response to skin warming Am J Physiol Heart Circ Physiol, January 1, 2009; 296(1): H51 - H56. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. M. Stewart, I. Taneja, N. Raghunath, D. Clarke, and M. S. Medow Intradermal angiotensin II administration attenuates the local cutaneous vasodilator heating response Am J Physiol Heart Circ Physiol, July 1, 2008; 295(1): H327 - H334. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. M. Stewart, I. Taneja, J. Glover, and M. S. Medow Angiotensin II type 1 receptor blockade corrects cutaneous nitric oxide deficit in postural tachycardia syndrome Am J Physiol Heart Circ Physiol, January 1, 2008; 294(1): H466 - H473. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. S. Thompson-Torgerson, L. A. Holowatz, N. A. Flavahan, and W. Larry Kenney Rho kinase-mediated local cold-induced cutaneous vasoconstriction is augmented in aged human skin Am J Physiol Heart Circ Physiol, July 1, 2007; 293(1): H30 - H36. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. J. Hodges, J. A. Traeger III, T. Tang, W. A. Kosiba, K. Zhao, and J. M. Johnson Role of sensory nerves in the cutaneous vasoconstrictor response to local cooling in humans Am J Physiol Heart Circ Physiol, July 1, 2007; 293(1): H784 - H789. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. M. Johnson Mechanisms of vasoconstriction with direct skin cooling in humans Am J Physiol Heart Circ Physiol, April 1, 2007; 292(4): H1690 - H1691. [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
