Accession Number : ADA291499

Title :   Control of Skin Blood Flow in the Neutral Zone of Human Body Temperature Regulation.

Descriptive Note : Final rept. for 1993,

Corporate Author : NAVAL HEALTH RESEARCH CENTER SAN DIEGO CA

Personal Author(s) : Savage, Margaret V. ; Brengelmann, George L. ; Roberts, Donald E. ; Pozos, Robert S.

PDF Url : ADA291499

Report Date : 04 NOV 1994

Pagination or Media Count : 37

Abstract : In humans, matching of heat loss and heat production in the "neutral" zone, defined operationally in terms of a range of skin temperatures (Tsk), is accomplished by regulation of skin blood flow (SkBF). In four men and four women, we investigated the control of SkBF in this range by setting Tsk at 33 deg C and 35 deg C in a square wave pattern (15 min at each temperature) or a step pattern (60 min at 33 deg C separating short periods at 35 deg C) by means of water sprayed over the entire body except the head, neck, and one forearm. Forearm blood flow (FBF) followed the pattern of Tsk, both in the forearm in which Tsk followed that of the rest of the body and in the arm exposed to room air (average local Tsk 31.22 deg C). Esophageal temperature (Tes) rose after Tsk fell and vice versa. This inverse relationship is predicted by a simple one- compartment thermal model in which control of SkBF is simulated as a linear combination of skin and core temperature (Tc). Similar patterns of Tsk applied to only one arm had little influence on FBF. We conclude that the feedforward reflex influence of Tsk on SkBF overcompensates for the effect of Tsk on thermal balance in the neutral zone so that equilibrium Tc has an inverse relationship to Tsk.

Descriptors :   *TEMPERATURE CONTROL, *HUMAN BODY, *BLOOD CIRCULATION, *BODY TEMPERATURE, THERMAL PROPERTIES, SETTING(ADJUSTING), CORES, PRODUCTION, MODELS, TEMPERATURE, HUMANS, AIR, NEUTRAL, WATER, COMPARTMENTS, PATTERNS, INVERSION, SPACE(ROOM), HEAT, MATCHING, WOMEN, HEAT BALANCE, SKIN(ANATOMY), HEAT LOSS, ARMS(ANATOMY), SKIN(GENERAL), NECK(ANATOMY), ESOPHAGUS, SQUARE WAVES.

Subject Categories : Stress Physiology
      Medicine and Medical Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE