BETA-ENDORPHIN AND PROPIOMELANOCORTIN-CORRELATES PEPTIDES RESPONSE INSUSPECTED AND CONFIRMED ISCHEMIC-HEART-DISEASE DURING EXERCISE

In this study, we investigated circulating beta-endorphin, ACTH and co rtisol in subjects with suspected coronary artery disease (CAD) and in patients with CAD during stress testing. croup I: 18 subjects, all ma le (average age 48 +/- 9 yrs) with suspected (CAD) were enroled. Group II: 35 patients, 30 males and 5 females (average age 54.3 +/- 7 yrs) with CAD, were enroled. Ten patients had previous myocardial infarctio n. In all patients that underwent coronarography a stenosis >75% was f ound in at least one coronary artery. The stress test was performed wi th a cycloergometer, increasing work loads 25 watt every 2 min. All su bjects and patients were in the recumbent position for at least 30 min utes prior to testing. During this period a 3-way catheter was placed in the antecubital vein and blood was drawn for beta-endorphin, ACTH a nd cortisol; additional blood samples were drawn using a pre-chilled s yringe at maximum effort and during the recovery period. Results: grou p I: 9 of the subjects with suspected CAD had either ECG or clinical s igns of ischemic during the stress test. In subjects with a negative t est, the test was carried out for a longer period of time and at a hig her work load. There was an increase in beta-endorphin and ACTH at pea k exercise and during recovery. Plasma cortisol increase during the pe riod of recovery. Group II: 16 of the 35 patients with CAD exhibited E CG signs of induced myocardial ischemia; there was no difference in wo rk loads in patients with positive or negative stress test. Exercise t ime was reduced in all patients and plasma beta-endorphin increased at peak exercise and recovery, in patients with a negative stress test. In conclusion our study, revealed a different response of beta-endorph in, ACTH and cortisol plasma levels in subjects with suspected CAD and in patients with CAD during exercise testing.