The role of baseline in the cutaneous vasoconstrictor responses during combined local and whole body cooling in humans

Gary J. Hodges, Wojciech A. Kosiba, Kun Zhao, Guy E. Alvarez, John M. Johnson

Research output: Contribution to journalArticlepeer-review

33 Scopus citations

Abstract

Previous work showed that local cooling (LC) attenuates the vasoconstrictor response to whole body cooling (WBC). We tested the extent to which this attenuation was due to the decreased baseline skin blood flow following LC. In eight subjects, skin blood flow was assessed using laser-Doppler flowmetry (LDF). Cutaneous vascular conductance (CVC) was expressed as LDF divided by blood pressure. Subjects were dressed in water-perfused suits to control WBC. Four forearm sites were prepared with microdialysis fibers, local heating/cooling probe holders, and laser-Doppler probes. Three sites were locally cooled from 34 to 28°C, reducing CVC to 45.9 ± 3.9, 42 ± 3.9, and 44.5 ± 4.8% of baseline (P < 0.05 vs. baseline; P > 0.05 among sites). At two sites, CVC was restored to precooling baseline levels with sodium nitroprusside (SNP) or isoproterenol (Iso), increasing CVC to 106.4 ± 12.4 and 98.9 ± 10.1% of baseline, respectively (P > 0.05 vs. precooling). Whole body skin temperature, apart from the area of blood flow measurement, was reduced from 34 to 31°C. Relative to the original baseline, CVC decreased (P < 0.05) by 44.9 ± 2.8 (control), 11.3 ± 2.4 (LC only), 29 ± 3.7 (SNP), and 45.8 ± 8.7% (Iso). The reductions at LC only and SNP sites were less than at control or Iso sites (P < 0.05); the responses at those latter sites were not different (P > 0.05), suggesting that the baseline change in CVC with LC is important in the attenuation of reflex vasoconstrictor responses to WBC.

Original languageEnglish (US)
Pages (from-to)H3187-H3192
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume293
Issue number5
DOIs
StatePublished - Nov 2007

Keywords

  • Cutaneous circulation
  • Isoproterenol
  • Nitric oxide

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

Fingerprint

Dive into the research topics of 'The role of baseline in the cutaneous vasoconstrictor responses during combined local and whole body cooling in humans'. Together they form a unique fingerprint.

Cite this