Journal of Applied Physiology, Vol 65, Issue 3 1082-1086, Copyright © 1988 by American Physiological Society

ARTICLES

Methylcholine-activated eccrine sweat gland density and output as a function of age

W. L. Kenney and S. R. Fowler
Laboratory for Human Performance Research, Pennsylvania State University, University Park 16802.

The purpose of this investigation was to examine eccrine sweat gland responsiveness to intradermal injections of methylcholine (MCh) across three age groups of men [young (Y) = 22-24; middle (M) = 33-40; older (O) = 58-67 yr old, n = 5 per group]. Subjects were matched with respect to maximum O2 consumption, body size, and body composition, and were thoroughly heat acclimated before participation. Randomly ordered concentrations of acetyl-beta-methylcholine chloride ranging from 0% (saline) to 0.1% (5 x 10(-3) M) were injected into the skin of the dorsal thigh in a thermoneutral environment, and activated sweat glands were photographed at 30-s intervals for the next 8 min. Density of MCh-activated glands was independent of both age and [MCh] (e.g., 2 min after injection of 5 x 10(-3) M [MCh]: Y = 45 +/- 7, M = 46 +/- 12, O = 42 +/- 5 glands/cm2). However, sweat gland output (SGO) per active gland was significantly lower for the O group and failed to increase with increasing [MCh] above 5 x 10(-4) M. When MCh (5 x 10(-3) M) was injected after 1 h of exercise in the heat, higher SGO's were elicited in each group; however, the SGO of the O group was again significantly lower than that of the Y group (91 +/- 11 vs. 39 +/- 4 ng/gland, P less than 0.02) with the M group intermediate (69 +/- 11 nl/gland; 2 min postinjection data).(ABSTRACT TRUNCATED AT 250 WORDS)

This article has been cited by other articles:

				W. L. Kenney and T. A. Munce Invited Review: Aging and human temperature regulation J Appl Physiol, December 1, 2003; 95(6): 2598 - 2603. [Abstract] [Full Text] [PDF]

				C. G. Crandall, M. Shibasaki, T. E. Wilson, J. Cui, and B. D. Levine Prolonged head-down tilt exposure reduces maximal cutaneous vasodilator and sweating capacity in humans J Appl Physiol, June 1, 2003; 94(6): 2330 - 2336. [Abstract] [Full Text] [PDF]

				N. Kondo, M. Shibasaki, K. Aoki, S. Koga, Y. Inoue, and C. G. Crandall Function of human eccrine sweat glands during dynamic exercise and passive heat stress J Appl Physiol, May 1, 2001; 90(5): 1877 - 1881. [Abstract] [Full Text] [PDF]

				M. Shibasaki and C. G. Crandall Effect of local acetylcholinesterase inhibition on sweat rate in humans J Appl Physiol, March 1, 2001; 90(3): 757 - 762. [Abstract] [Full Text] [PDF]

				M. N Sawka and S. J Montain Fluid and electrolyte supplementation for exercise heat stress Am. J. Clinical Nutrition, August 1, 2000; 72(2): 564S - 572. [Abstract] [Full Text] [PDF]