Increased local angiotensin II formation in aneurysmal aorta.
We investigated the levels and locations of angiotensin II-forming enzymes, angiotensin converting enzyme (ACE) and chymase, in aneurysmal and normal aortas. Aneurysmal aortic specimens (n = 14) were obtained at the time of operative aneurysm repair from 14 patients ranging in age from 57 to 84 y. Normal aortic specimens (n = 16) were obtained from 16 patients (48 to 72 y) who underwent coronary artery bypass surgery. The ACE and chymase activities were determined using each specimen. Sections of each specimen were immunostained with antibodies for ACE and chymase. The ACE activities in the aneurysmal and normal aortas were 0.82 +/- 0.10 and 0.14 +/- 0.05 mU/mg protein, respectively, and this difference was significant. The chymase activities in the aneurysmal and normal aortas were 17.9 +/- 2.40 and 1.02 +/- 0.18 mU/mg protein, respectively, and this difference was also significant. In the aneurysmal aorta, ACE-positive cells were detected with macrophages in the intima and media and chymase-positive cells were detected with mast cells in the media and adventitia, whereas positive ACE and chymase cells in the normal aorta were located only in the endothelium and adventitia, respectively. Angiotensin II-forming enzymes, chymase and ACE, were significantly increased in the aneurysmal aorta, and increased angiotensin II may be associated with the development of aneurysmal formations.
Department of Pharmacology, Osaka Medical College, 2-7 Daigaku-cho, Takatsuki City, Osaka 569-8686, Japan.
Masayoshi
M
Nishimoto
Shinji
S
Takai
Hitoshi
H
Fukumoto
Koutaro
K
Tsunemi
Atsushi
A
Yuda
Yoshihide
Y
Sawada
Mayumi
M
Yamada
Denan
D
Jin
Masato
M
Sakaguchi
Yasuhisa
Y
Nishimoto
Shinjiro
S
Sasaki
Mizuo
M
Miyazaki
D000368:Aged; D000369:Aged, 80 and over; D000804:Angiotensin II / Q000096:biosynthesis*; D001011:Aorta / Q000201:enzymology / Q000378:metabolism; D001014:Aortic Aneurysm / Q000201:enzymology / Q000378:metabolism*; D053818:Chymases; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism; D012697:Serine Endopeptidases / Q000378:metabolism
D000804:Angiotensin II; D007703:Peptidyl-Dipeptidase A; D012697:Serine Endopeptidases; D053818:Chymases