Cardiac remodeling and angiotensin II-forming enzyme activity of the left ventricle in hamsters with chronic pressure overload induced by ascending aortic stenosis.
Cardiac remodeling and angiotensin II-forming enzyme activity of the left ventricle on chronic pressure overload were studied in male Syrian hamsters, whose chymase activity is similar to that of dogs. Pressure overload was achieved by banding at the ascending aorta (aortic stenosis). Echocardiography, histological analysis, and analysis of cardiac angiotensin-converting enzyme and chymase-like activities were performed. At 10 weeks after banding, concentric hypertrophy of the left ventricle was evident. At 20 weeks after banding, the ventricular weight-to-body ratio, cardiac fibrosis, and cardiac chymase-like activity were significantly increased, while cardiac angiotensin-converting enzyme activity was significantly decreased. This suggests that cardiac chymase, compared with cardiac angiotensin-converting enzyme, was activated against the chronic pressure overload and was responsible for the cardiac remodeling through the formation of angiotensin II. Considering the utility of the rodents, the interspecies similarity of the Ang II-forming pathway, and the effect of chymase in the hamsters, the present model is considered useful for studies evaluating the effect of Ang II and chymase in the canine heart with chronic pressure overload.
Shimizu
Miki
M
Department of Veterinary Surgery, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchushi, Tokyo 183-0054, Japan.
Tanaka
Ryou
R
Fukuyama
Tomoki
T
Aoki
Ryoko
R
Orito
Kensuke
K
Yamane
Yoshihisa
Y
D000804:Angiotensin II / Q000096:biosynthesis; D000818:Animals; D001024:Aortic Valve Stenosis / Q000150:complications / Q000473:pathology / Q000662:veterinary; D001835:Body Weight / Q000502:physiology; D053818:Chymases; D006224:Cricetinae; D004195:Disease Models, Animal; D004283:Dog Diseases / Q000201:enzymology / Q000473:pathology; D004285:Dogs; D004452:Echocardiography; D006333:Heart Failure / Q000201:enzymology / Q000473:pathology / Q000662:veterinary*; D006352:Heart Ventricles / Q000473:pathology; D006651:Histocytochemistry; D008297:Male; D008647:Mesocricetus; D009206:Myocardium / Q000201:enzymology; D009929:Organ Size; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*; D012697:Serine Endopeptidases / Q000378:metabolism*; D020257:Ventricular Remodeling / Q000502:physiology*
D000804:Angiotensin II; D007703:Peptidyl-Dipeptidase A; D012697:Serine Endopeptidases; D053818:Chymases