HORMONAL ALTERATIONS IN MEN EXPOSED TO HEAT AND COLD STRESS

Abstract

THE adrenal cortex plays a role in the body's defense against cold (1, 2, 3, 4), but the precise nature of this role has not been clarified. Bilateral destruction of the adrenal gland diminishes resistance to varying types of stress including muscular exercise, burns, infections, shock, trauma, anoxia and cold (2). Histologic studies reveal adrenal hypertrophy (5, 6, 7), and chemical studies show a diminution in the cholesterol and ascorbic acid content of the adrenal cortex in rats exposed to cold (8, 9). In fact, so well established is the relationship between the adrenal cortex and the stimulus of cold, that the latter is used as a standard stress in the biologic assay of adrenal cortical extracts (10). Indirect evidence that outpouring of the adrenal cortical hormones is responsible for the changes seen in the “general adaptation syndrome” (11) is provided by experimental administration of adrenal cortical extracts (12). There is involution of thymus and lymphoid tissue and fall in circulating lymphocytes following injection of adrenal cortical extracts. The lymphocyte fall has been used as a criterion for adrenal response to stress in human beings (13, 14, 15).