Atrial natriuretic peptide release due to physical exercise in healthy persons and in cardiac patients.

Plasma levels of human atrial natriuretic peptide were determined during different stages of a symptom-limited bicycle ergometer stress test. Eight healthy persons and three patients suffering from well-defined cardiac disorders were examined. Measurements of the peptide were performed before the exercise, at 75 watts, at maximal work load, and 10 and 30 min after ceasing the exercise. In healthy persons plasma levels of the peptide increased from preexercise levels of 4-41 ng/l to 16-59 ng/l at maximal work load, but remained in the normal range (10-70 ng/l). In contrast, in the cardiac patients, levels of the peptide were up to 8-fold higher at maximal physical exertion (154-270 ng/l) than at rest (34-86 ng/l). Within a recovery period of 30 min hormone concentrations returned almost to preexercise levels.