HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 289/5/R1354    most recent 00804.2004v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (10) Citing Articles via Google Scholar Google Scholar Articles by Okazaki, K. Articles by Levine, B. D. Search for Related Content PubMed PubMed Citation Articles by Okazaki, K. Articles by Levine, B. D.

NEUROHUMORAL CONTROL OF CARDIOVASCULAR FUNCTION

Vasoconstriction during venous congestion: effects of venoarteriolar response, myogenic reflexes, and hemodynamics of changing perfusion pressure

Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas, and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas

Submitted 29 November 2004 ; accepted in final form 6 July 2005

We dissected the relative contribution of arteriovenous hemodynamics, the venoarteriolar response (VAR), and the myogenic reflex toward a decrease in local blood flow induced by venous congestion. Skin blood flow (SkBF) was measured in 12 supine subjects via laser-Doppler flowmetry 1) over areas of forearm and calf skin, in which the VAR was blocked by using eutectic mixture of local anesthetics (EMLA sites) and 2) over the contralateral forearm or calf skin (control sites), using two different techniques: limb dependency of 23–37 cm below the heart and cuff inflation to 40 mmHg. During limb dependency, SkBF decreased at the control sites, whereas it remained unchanged at the EMLA sites. In contrast, during cuff inflation, SkBF decreased at the control sites and also decreased at the EMLA sites. The percent change in SkBF from baseline was greater during cuff inflation than limb dependency at both the control sites and the EMLA sites. Estimated skin vascular resistance remained unchanged at the EMLA sites during cuff inflation, as well as limb dependency. Thus the decrease in SkBF during venous congestion with cuff inflation is not solely due to the cutaneous VAR but also to a reduction in local perfusion pressure. The VAR is therefore most specifically quantified by venous congestion induced by limb dependency, rather than cuff inflation. Finally, from both techniques, we calculated that during venous congestion induced by limb dependency (calf), 45% of the nonbaroreflex vasoconstriction is induced by the VAR and 55% by the myogenic reflex.

local circulatory control; axon reflex

This article has been cited by other articles:

				M. E. J. Lott, C. Hogeman, M. Herr, M. Bhagat, A. Kunselman, and L. I. Sinoway Vasoconstrictor responses in the upper and lower limbs to increases in transmural pressure J Appl Physiol, January 1, 2009; 106(1): 302 - 310. [Abstract] [Full Text] [PDF]

				M. E. J. Lott, C. Hogeman, M. Herr, M. Bhagat, and L. I. Sinoway Sex differences in limb vasoconstriction responses to increases in transmural pressures Am J Physiol Heart Circ Physiol, January 1, 2009; 296(1): H186 - H194. [Abstract] [Full Text] [PDF]

				A. Gabrielsen and P. Norsk Effect of spaceflight on the subcutaneous venoarteriolar reflex in the human lower leg J Appl Physiol, September 1, 2007; 103(3): 959 - 962. [Abstract] [Full Text] [PDF]

				M. Kooijman, M. de Hoog, G. A. Rongen, H. J. M. van Kuppevelt, P. Smits, and M. T. E. Hopman Local vasoconstriction in spinal cord-injured and able-bodied individuals J Appl Physiol, September 1, 2007; 103(3): 1070 - 1077. [Abstract] [Full Text] [PDF]

				J. M. Stewart, M. S. Medow, N. S. Cherniack, and B. H. Natelson Postural hypocapnic hyperventilation is associated with enhanced peripheral vasoconstriction in postural tachycardia syndrome with normal supine blood flow Am J Physiol Heart Circ Physiol, August 1, 2006; 291(2): H904 - H913. [Abstract] [Full Text] [PDF]