Changes in angiotensin-converting enzyme activity and angiotensin I level in asthmatic and healthy children after submaximal physical work.

The changes in angiotensin-converting enzyme activity and serum angiotensin I levels have been studied in 16 controls subjected to submaximal physical work. Baseline (Pre-exercise) angiotensin I levels were identical in both groups. Physical exercise caused an elevation that was more marked in the asthmatic group than in the control group. The activity of serum angiotensin-converting enzyme differed in the two groups even before physical exercise, the asthmatic children having exhibited an activity level significantly lower than that of the healthy controls. after submaximal work, the enzyme activity increased in healthy subjects but decreased in asthmatic children.