title: Metabolism and subcellular localization of angiotensin converting enzyme in cultured human monocytes.
abstract: The enhancement of monocyte ACE activity during culture by autologous T-lymphocytes was shown to be due to a stimulation of the rate of ACE synthesis. The rate of synthesis increased from 0.020 mU/10(6) monocytes/hr in monocytes cultured alone to 0.063 mU/10(6) monocytes/hr in monocytes co-cultured with T-lymphocytes. The presence of T-lymphocytes during culture did not alter the rate of ACE degradation observed in monocytes cultured alone. The ACE induced in monocytes by T-lymphocytes appears to be an ecto-enzyme. Brief exposure to diazosulfanilic acid (10(-3) M) and papain (250 micrograms/ml) reduced ACE activity 89% and 66%, respectively, without appreciably altering the activity of the cytosolic enzyme, lactate dehydrogenase.
mesh_terms: D000328:Adult; D002478:Cells, Cultured; D003979:Diazonium Compounds / Q000494:pharmacology; D006801:Humans; D009000:Monocytes / Q000166:cytology / Q000201:enzymology*; D010206:Papain / Q000378:metabolism; D007703:Peptidyl-Dipeptidase A / Q000097:blood*; D013347:Subcellular Fractions / Q000201:enzymology; D013425:Sulfanilic Acids / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology; D013997:Time Factors
chemical_list: D003979:Diazonium Compounds; D013425:Sulfanilic Acids; D007703:Peptidyl-Dipeptidase A; D010206:Papain; C000469:diazobenzenesulfonic acid