Steroid and catecholamine studies on pilots during prolonged experiments in a space cabin simulator

¹ Environmental Systems Branch, Department of Bioastronautics, USAF School of Aerospace Medicine, Aerospace Medical Division (AFSC), Brooks Air Force Base, Texas

Urinary excretion of 17-hydroxycorticosteroids, corticosterone-like hormones, and catecholamines (epinephrine and norepinephrine) has been investigated on pilots during prolonged experiments in a two-man space cabin simulator. The experimental profiles were: 1) two 17-day experiments at ground level; 2) two 14-day experiments at 27,000 ft; and 3) four experiments at 33,500 ft lasting 17 days. In the latter two groups the atmosphere was essentially 100% O₂. The hormone parameters indicate that conditions imposed by the experimental procedures were no more stressful to the subjects than undergoing extensive medical examinations as observed from pre- and postexperimental values. The only significant trend was the continuous linear increase in the excretion of corticosterone-like hormones. There were borderline indications that the excretion of 17-hydroxycorticosteroids and norepinephrine were altitude dependent. Extraordinary occurrences in the simulator were correlated with increased catecholamine and steroid excretion. The correlation coefficients and the analyses of variance for the four hormone parameters were calculated and discussed.

Submitted on March 26, 1963