BAPN-induced rodent model of aortic dissecting aneurysm and related complications.

Background: The aim of this study was to investigate the effects of beta-aminopropionitrile (BAPN) on the arterial walls of rodents, and to analyze the gross or pathological changes of arterial and other tissues of rodents treated with BAPN at different concentrations or doses.

Methods: Eighteen SPF SD rats (4-5-week old) were divided into three groups: SD-0.2 (Group A), SD-0.4 (Group B), and SD-0.6 (Group C). The groups A, B and C were given 0.2%, 0.4%, and 0.6% BAPN solution, respectively, as drinking water for seven weeks. Forty SPF C57BL/6 mice (3-week old) were randomly divided into four groups: C57-0.2 (Group D), C57-0.4 (Group E), C57-0.6 (Group F) and the control group and given 0.2%, 0.4%, or 0.6% BAPN or distilled water as drinking water, respectively, for seven weeks. All experimental animals were free to drink water. The aortas were dissected and visually examined. At the same time, hematoxylin and eosin (HE) staining was performed in aorta tissue. The vascular diameter and area of the middle membrane were measured with IPP (Image-Pro Plus 6.0).

Results: BAPN treatment significantly affected the water intake and weight gain of rats and mice. BAPN also caused thickening of the membrane in the aortas of rats and mice, and irregularity in the arrangement of elastic fibers. These pathological changes are similar to the pathological changes observed in human aneurysms. The incidence of dissecting aneurysm in C57 mice was higher than that of Sprague Dawley (SD) rats.

Conclusions: BAPN at a concentration of 0.4% was feasible to produce an animal model of dissecting aneurysm. In SD rats, the rate of pathological changes and other complications, such as intestinal rupture and scoliosis, was higher than the rates of dissecting aneurysm.