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

This Article Full Text Free Full Text (PDF) Free All Versions of this Article: 99/6/2294    most recent 00500.2005v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI 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 ISI Web of Science (5) Citing Articles via Google Scholar Google Scholar Articles by Wilkins, B. W. Articles by Minson, C. T. Search for Related Content PubMed PubMed Citation Articles by Wilkins, B. W. Articles by Minson, C. T.

Vasoactive intestinal peptide fragment VIP_10–28 and active vasodilation in human skin

¹Department of Human Physiology, and ²Institute of Neuroscience, University of Oregon, Eugene, Oregon

Submitted 2 May 2005 ; accepted in final form 9 August 2005

A recent study reported the vasoactive intestinal peptide (VIP) fragment VIP_10–28 inhibited the rise in skin blood flow during heat stress. Our laboratory has reported that the nitric oxide (NO) pathway and histamine receptor-1 (H1)-receptor activation is common to both exogenous VIP-mediated dilation and active vasodilation (AVD). The present study aimed to further examine the specific role for VIP in AVD by using VIP_10–28 to antagonize VIP-mediated dilation in the presence of NO synthase (NOS) inhibition and an H1 antagonist. Study 1 (n = 12) examined whether VIP_10–28 antagonizes vasodilation to exogenous VIP via inhibition of NO-dependent mechanisms. Study 2 (n = 6) investigated AVD in skin sites receiving VIP_10–28 alone and in combination with NOS inhibition. Study 3 (n = 6) examined AVD in sites receiving VIP_10–28 alone and combined VIP_10–28 and H1 antagonism. Due to differences in our findings and those previously published, study 4 (n = 6) investigated whether an increase in baseline skin blood flow could result in a diminished rise in AVD. Red blood cell flux was measured using laser Doppler flowmetry, and cutaneous vascular conductance (flux/mean arterial pressure) was normalized to maximal vasodilation (28 mM sodium nitroprusside). VIP_10–28 augmented vasodilation to exogenous VIP (P < 0.05 vs. control) and hyperthermia (P < 0.05 vs. control). NOS inhibition had no effect on the augmented dilation during exogenous VIP or hyperthermia (P > 0.05). Similarly, H1-receptor antagonists had no effect on the augmented dilation during hyperthermia (P > 0.05 vs. VIP_10–28). In study 4, percentage of maximal cutaneous vascular conductance was attenuated when baseline skin blood flow was elevated before whole body heating. Our results suggest that VIP_10–28 may be an unsuitable antagonist for examining a role for VIP-mediated dilation in human skin.

histamine receptor-1; cutaneous vascular conductance

This article has been cited by other articles:

				D. L. Kellogg Jr., G. J. Hodges, C. R. Orozco, T. M. Phillips, J. L. Zhao, and J. M. Johnson Cholinergic mechanisms of cutaneous active vasodilation during heat stress in cystic fibrosis J Appl Physiol, September 1, 2007; 103(3): 963 - 968. [Abstract] [Full Text] [PDF]

				B. W. Wilkins, E. A. Martin, S. K. Roberts, and M. J. Joyner Preserved reflex cutaneous vasodilation in cystic fibrosis does not include an enhanced nitric oxide-dependent mechanism J Appl Physiol, June 1, 2007; 102(6): 2301 - 2306. [Abstract] [Full Text] [PDF]

				J. M. Johnson How does skin blood flow get so high? J. Physiol., December 15, 2006; 577(3): 768 - 768. [Full Text] [PDF]

				B. J. Wong and C. T. Minson Neurokinin-1 receptor desensitization attenuates cutaneous active vasodilatation in humans J. Physiol., December 15, 2006; 577(3): 1043 - 1051. [Abstract] [Full Text] [PDF]

				K. Aoki, D. P. Stephens, K. Zhao, W. A. Kosiba, and J. M. Johnson Modification of cutaneous vasodilator response to heat stress by daytime exogenous melatonin administration Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2006; 291(3): R619 - R624. [Abstract] [Full Text] [PDF]