Lung peptidases, including carboxypeptidase, modulate airway reactivity to intravenous bradykinin.
Chodimella-V; Skidgel-RA; Krowiak-EJ; Murlas-CG
Am Rev Respir Dis 1991 Oct; 144(4):869-874
A study was undertaken to determine the effect of inhibition of endogenous carboxypeptidase, neutral endopeptidase, or angiotensin converting enzyme on airway reactivity to the peptide hormone bradykinin. Specific airway resistance was measured in male Hartley- guinea-pigs before and after receiving intravenous injections of the enzyme inhibitors 2-mercaptomethyl-3-guanidinoethylthiopropanoic- acid (MGTA), phosphoramidon, or captopril. Reactivity to increasing doses of intravenous bradykinin was measured in guinea-pigs following these exposures. Phosphoramidon and captopril, either alone or in combination, were observed to increase airway reactivity to bradykinin, but did not affect muscarinic activity. MGTA did not have any significant effect on airway reactivity, although it was associated with significantly increased reactivity in the presence of phosphoramidon and captopril. The authors conclude that airway reactivity to bradykinin is regulated by lung cell membrane carboxypeptidase, endopeptidase, and angiotensin converting enzyme, and that the influence of carboxypeptidase increases when the activities of neutral endopeptidase and angiotensin converting enzyme are reduced.
NIOSH-Publication; NIOSH-Grant; Pulmonary-system-disorders; Pulmonary-function; Enzymes; Hormone-activity; Enzyme-inhibitors; Lung-function; Physiological-response; Physiological-function
Christopher Murlas, M.D., Department of Medicine (Pulmonary), Rush University, 1653 West Congress Parkway, Chicago, IL 60612
American Review of Respiratory Disease
University of Cincinnati, Cincinnati, Ohio