Journal
AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY
Volume 305, Issue 8, Pages R877-R885Publisher
AMER PHYSIOLOGICAL SOC
DOI: 10.1152/ajpregu.00290.2013
Keywords
sweating; aging; laser-Doppler flowmetry; skin blood flow; sweating
Categories
Funding
- National Institute on Aging [R01-AG-007004-22]
- American College of Sports Medicine Foundation
Ask authors/readers for more resources
Aging is associated with attenuated thermoregulatory function that varies regionally over the body. Decrements in vasodilation and sweating are well documented with age, yet limited data are available concerning the regional relation between these responses. We aimed to examine age-related alterations in the relation between regional sweating (RSR) and skin blood flow (SkBF) to thermal and pharmacological stimuli. Four microdialysis fibers were inserted in the ventral forearm, abdomen, thigh, and lower back of eight healthy aged subjects (64 +/- 7 yr) and nine young (23 +/- 3 yr) during 1) ACh dose response (1 +/- 10(-7) to 0.1 M, mean skin temperature 34 C) and 2) passive whole body heating to Delta 1 degrees C rise in oral temperature (Tor). RSR and SkBF were measured over each microdialysis membrane using ventilated capsules and laser-Doppler flowmetry. Maximal SkBF was measured at the end of both protocols (50 mM SNP). Regional sweating thresholds and RSR were attenuated in aged vs. young at all sites (P < 0.0001) during whole body heating. Vasodilation thresholds were similar between groups (P > 0.05). Attenuated SkBF were observed at the arm and back in the aged, representing 56 and 82% of those in the young at these sites, respectively (0.5 Delta T-or). During ACh perfusion, SkBF (P = 0.137) and RSR were similar between groups (P = 0.326). Together these findings suggest regional age-related decrements in heat-activated sweat gland function but not cholinergic sensitivity. Functional consequences of such thermoregulatory impairment include the compromised ability of older individuals to defend core temperature during heat exposure and a subsequently greater susceptibility to heat-related illness and injury.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available