1978 Volume 16 Issue 11 Pages 836-839
Serum angiotension I-converting enzyme (ACE) activity was measured in various pulmonary disease. Serum ACE activity was measured by using Hippuryl-Histidayl-Leucine (Hip-His-Leu) as a substrate according to Cushman and Cheung. Diseases were as follows: sarcoidosis 36 cases, diffuse interstitial fibrosing pneumonitis 11 cases, asbestosis 8 cases, silicosis 7 cases, organic dust pneumoconiosis 14 cases, advanced pulmonary tuberculosis 9 cases, chronic obstructive lung disease 11 cases, pulmonary cancer 23 cases.
Serum ACE activity in active sarcoidosis patients was significantly high, 37.6±2.4nmol/ml/min, compared with normal subjects, 20.5±0.8nmol/ml/min. ACE activities in chronic obstructive lung disease and in lung cancer were 15.0±2.47nml/ml/min and 14.57±1.52nmol/ml/min, respectively. Both were significantly low compared with normal subjects. There were no significant differences of serum ACE activity among other diseases.
To find out the effect of pulmonary function on serum ACE level, the relation between vital capacity (%VC) and serum ACE level was studied. There was no correlationship between them. There were 10 cases which showed lower serum ACE activity than the normal range (less than 10nmol/ml/min). Five cases were pulmonary cancer and the remaining 5 cases were chronic obstructive lung disease. There was no special correlation between histological characteristics of lung cancer and serum ACE. Serum ACE levels showed neither the severity of the symptoms nor the duration of the disease.
It is concluded that the serum ACE activity has a diagnostic value only in sarcoidosis.
