Accession Number : AD0663845

Title :   THE ROLE OF ADRENAL CORTEX IN THE PROCESS OF ACCLIMATIZATION TO HIGH ALTITUDES.

Descriptive Note : Final rept.,

Corporate Author : UNIVERSIDAD PERUANA CAYETANO HEREDIA LIMA INSTITUTO DE INVESTIGACIONES DE LA ALTURA

Personal Author(s) : Moncloa,Federico

Report Date : OCT 1967

Pagination or Media Count : 15

Abstract : Adrenal function and cortisol metabolism during acute exposure of sea level natives to 4,300 meters of altitude were studied. The results show the following: (a) Cortisol secretion rate is temporarily increased correlating with increases in its plasma concentration and in the urinary excretion of its metabolites; (b) Hypoxia does not result in a maximal stimulus for the adrenal cortex since it can be further stimulated by exogenous corticotrophin; (c) The adrenocortical response to high altitude can be blocked by the administration of dexamethasone; (d) The second compartment in which cortisol is distributed is diminished. This may be related with the contraction of the radiosulfate space, observed under the same experimental conditions; and (e) The metabolic clearance rate of cortisol is not significantly altered. Corticotrophin half-life (t 1/2) was also studied. Results indicate that a 24 aminoacids ACTH has a t 1/2 slightly longer than a 39 aminoacids ACTH. Using the same type of experiments the t 1/2 of the 39 aminoacids ACTH in 11 high altitude natives was also investigated. The results were similar to the ones obtained in the sea level controls. (Author)

Descriptors :   (*ACCLIMATIZATION, *ADRENAL CORTEX), ADRENAL CORTEX HORMONES, STEROIDS, SECRETION, HYPOXIA, TOLERANCES(PHYSIOLOGY), METABOLISM, STRESS(PHYSIOLOGY), CORTICOSTEROID AGENTS, URINE, EXCRETION, HIGH ALTITUDE, ADRENOCORTICOTROPIC HORMONE, HALF LIFE

Subject Categories : Anatomy and Physiology
      Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE