Investigating the roles of core and local temperature on forearm skin blood flow.
Microvasc Res
; 106: 88-95, 2016 07.
Article
en En
| MEDLINE
| ID: mdl-27072118
ABSTRACT
We sought to isolate the contributions of core and local temperature on forearm skin blood flow (SkBF), and to examine the interaction between local- and reflexive-mechanisms of SkBF control. Forearm SkBF was assessed using laser-Doppler flowmetry in eight males and eight females during normothermia and hyperthermia (+1.2°C rectal temperature). Mean experimental forearm temperature was manipulated in four, 5min blocks between neutral (A 33.0°C) and warm (B 38.5°C) in an A-B-A-B fashion during normothermia, and B-A-B-A during hyperthermia. Mean control forearm skin temperature was maintained at ~33°C. Finally, local heating to 44°C was performed on both forearms to elicit maximal SkBF. Data are presented as a percentage of maximal cutaneous vascular conductance (CVC), calculated as laser-Doppler flux divided by mean arterial pressure. No sex differences were observed in any CVC measures (P>0.05). During normothermia, increasing experimental forearm temperature to 38.5°C elevated CVC by 42±8%max (d=3.1, P<0.001). Subsequently decreasing experimental forearm temperature back down to 33.0°C reduced CVC by 36±7%max (d=2.5, P<0.001). Finally, the second increase in experimental forearm temperature to 38.5°C increased CVC by 25±6%max (d=1.9, P<0.0001). During hyperthermia, decreasing experimental forearm temperature to 33.0°C reduced CVC by 6±1%max (d=0.5, P<0.001). Increasing experimental forearm temperature to 38.5°C increased CVC by 4±2%max (d=0.4, P<0.001). Finally, decreasing experimental forearm temperature to 33.0°C reduced CVC by 8±2%max (d=0.7, P<0.001). Compared to normothermia, CVC responses to local temperature changes during hyperthermia were almost abolished (normothermia d=1.9-3.1; hyperthermia d=0.4-0.7). These data indicate that local temperature drives SkBF during normothermia, while reflexive mechanisms regulate SkBF during hyperthermia.
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Banco de datos:
MEDLINE
Asunto principal:
Piel
/
Vasodilatación
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Sistema Vasomotor
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Regulación de la Temperatura Corporal
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Fiebre
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Microcirculación
Límite:
Adult
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Female
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Humans
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Male
Idioma:
En
Año:
2016
Tipo del documento:
Article