The local training effect of secretory activity on the response of eccrine sweat glands

Abstract

The influence of repeatedly raising the body temperature by radiant heat to a level at which acclimatization to heat is normally acquired was investigated in 2 series of experiments, the 1st without the subjects sweating, the 2nd with sweating. In a 2nd investigation local sweat-gland activity was induced by drug injections on successive days without raising the body temperature. These experiments show that the increased sweating capacity characteristic of acclimatization to heat is a result of sweat-gland activity and does not appear to be induced by or to depend on an elevated body temperature. Secretory activity results in a loss of glycogen from sweat-gland cells on the 1st day of heat exposure but not after the glands have been "trained" by acclimatization to heat. The state of acclimatization has no influence on the threshold concentration of acetylcholine required to elicit sweating when injected intradermally.