The influence of aspirin on exercise-induced changes in adrenocorticotrophic hormone (ACTH), cortisol and aldosterone (ALD) concentrations.

Abstract

The influence of aspirin (ASA) on the endocrinology system and prostaglandin (PGs) synthesis is not completely clear. The aim of the study was to estimate the influence of ASA on the changes in the concentration of ACTH, cortisol and aldosterone (ALD) induced by physical exercise. This study was conducted on 19 healthy students (age 21-23 years). They were subjected to intensive physical exercise on a cycle ergometer. On the day prior to the experiment, 12 subjects took two 0.5-g doses of ASA in a wafer, and another 0.5 g 3-4 h before the test on the day of the investigation (ASA group). The remaining seven subjects (control group) received placebo. Hematocrit, lactate concentration and concentrations of ACTH, cortisol and ALD were determined before exercise, after exercise, and after 30 min of recovery, in a blood sample taken from a cubital vein. Before exercise, the degree of platelet aggregation in response to arachidonic acid was estimated, in order to confirm the correct allocation to the two groups. Aggregation should only occur in the ASA group. ASA and control groups exercised for 30.3 (3.1) min and 30.2 (1.6) min, respectively. Maximal heart rate and lactate concentration were similar in both groups, as were the basal concentrations of ACTH and cortisol; the ALD concentration seemed lower in the ASA group, but the difference was not significant (p<0.1). In both groups after exercise ACTH, cortisol and ALD concentrations were significantly increased, however when compared to the control group, the increase of ACTH in the ASA group was significantly higher, and ALD increase significantly lower. After recovery there was a significant decrease in ACTH concentration, whereas the concentrations of ALD and cortisol did not change. The concentrations of cortisol in both groups after exercise and recovery were similar. That is most likely because the ACTH concentrations in the ASA and control groups were sufficient for almost maximal cortisol secretion. It is proposed that ASA administration caused prostaglandin synthesis to decrease, and that this led to a lower basal concentration of ALD and a significantly lower level of ALD after exercise.