Morphologic changes in the aorta during elastase infusion in the rat aneurysm model.
BACKGROUND
The morphologic changes in the aorta during elastase infusion, which have not previously been investigated, were examined in the rat abdominal aortic aneurysm model.


METHODS
A total of 80 Wistar rats were divided into five groups. A 1.0-cm segment of infra-renal abdominal aorta was infused with 25 U of elastase in 1 mL saline for 10 (n = 14), 20 (n = 14), 30 (n = 14), 60 (n = 19), or 120 min (n = 19). In the 120-min group, transparency and aortic diameter were recorded every 10 min. In each group, 7 rats were killed immediately after infusion. The aortas were excised for histologic examination. The aortic diameters were measured 7 days after infusion in the remaining rats.


RESULTS
The infused aorta became transparent within 50 min of elastase infusion. The aortic diameter increased rapidly for the first 30 min of infusion. Histologically, the elastic tissue was completely absent after 60 min of infusion. The aortic diameters in the 60- and 120-min groups were not significantly different 7 days after infusion.


CONCLUSIONS
Morphologic changes in the infused aorta are complete after 60 min of elastase infusion. It may be possible to shorten the elastase infusion time from 120 to 60 min in this model.
Yamaguchi
T
T
First Department of Surgery, Toyama Medical and Pharmaceutical University, Toyama, Japan. surg1@ms.toyama-mpu.ac.jp
Yokokawa
M
M
Suzuki
M
M
Higashide
S
S
Katoh
Y
Y
Sugiyama
S
S
Misaki
T
T
D000818:Animals; D001012:Aorta, Abdominal / Q000187:drug effects / Q000473:pathology* / Q000503:physiopathology; D017544:Aortic Aneurysm, Abdominal / Q000139:chemically induced / Q000473:pathology* / Q000503:physiopathology; D004195:Disease Models, Animal; D007261:Infusions, Intra-Arterial; D008297:Male; D010196:Pancreatic Elastase / Q000008:administration & dosage / Q000633:toxicity*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D010196:Pancreatic Elastase