title: Heterogeneous distribution of angiotensin I-converting enzyme (CD143) in the human and rat vascular systems: vessel, organ and species specificity.
abstract: Angiotensin I-converting enzyme (kininase II, ACE, CD143) availability is a determinant of local angiotensin and kinin concentrations and physiological actions. Limited information is available on ACE synthesis in peripheral vascular beds. We studied the distribution of ACE along the human and rat vascular tree, and determined whether the enzyme was uniformly distributed in all endothelial cells (EC) or if differences occurred among vessels and organs. The distribution of ACE was assessed by using a panel of anti-human ACE monoclonal antibodies and serial sections of the entire vascular tree of humans. Comparison was made with other EC markers. EC of small muscular arteries and arterioles displayed high ACE immunoreactivity in all organs studied except the kidney, while EC of large arteries and of veins were poorly reactive or completely negative. Only 20% on average of capillary EC in each organ, including the heart, stained for ACE, with the remarkable exception of the lung and kidney. In the lung all capillary EC were labeled intensively for ACE, whereas in the kidney the entire vasculature was devoid of detectable enzyme. In contrast to the man, the rat showed homogeneous endothelial expression of ACE in all large and middle-sized arteries, and in veins, but in renal vessels ACE expression was reduced. This study documents a vessel, organ and species specific pattern of distribution of endothelial ACE. The markedly reduced ACE content of the renal vasculature may protect the renal circulation against excess angiotensin II formation and kinin depletion, and maintain high renal blood flow.
authors.affiliation: Department of Pediatric Surgery, University of Leipzig, Leipzig, Germany. Roman.Metzger@medizin.uni-leipzig.de
authors.forename: Roman
authors.initials: R
authors.lastname: Metzger
authors.forename: Folker E
authors.initials: FE
authors.lastname: Franke
authors.forename: Rainer M
authors.initials: RM
authors.lastname: Bohle
authors.forename: François
authors.initials: F
authors.lastname: Alhenc-Gelas
authors.forename: Sergei M
authors.initials: SM
authors.lastname: Danilov
mesh_terms: D000328:Adult; D000368:Aged; D000825:Animal Structures / Q000098:blood supply / Q000378:metabolism*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001158:Arteries / Q000378:metabolism; D001808:Blood Vessels / Q000378:metabolism*; D003331:Coronary Vessels / Q000378:metabolism; D042783:Endothelial Cells / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007668:Kidney / Q000098:blood supply / Q000502:physiology; D008168:Lung / Q000098:blood supply / Q000378:metabolism; D016253:Microscopy, Immunoelectron; D055806:Microvessels / Q000378:metabolism; D008875:Middle Aged; D009928:Organ Specificity / Q000502:physiology*; D007703:Peptidyl-Dipeptidase A / Q000276:immunology / Q000378:metabolism*; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D011180:Postmortem Changes; D051381:Rats; D011917:Rats, Inbred Lew; D017208:Rats, Wistar; D013045:Species Specificity; D014680:Veins / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D007703:Peptidyl-Dipeptidase A