A DISSECTING AORTIC ANEURYSM MODEL INDUCED BY N-(2-AMINOETHYL) ETHANOLAMINE IN RATS

Ya Xu, M.D., Ph.D., Y. Yang, M.D., J. Ruiz, M.S., A.M. Purgason, M.S. and P.J. Boor, M.D.

Department of Pathology, UTMB

Background: Dissecting aortic aneurysm (DAA) is a tear in the wall of the aorta that causes blood to flow between the layers of the media of the aorta and forces the layers apart. Aortic dissection is a medical emergency and can quickly lead to death, even with optimal treatment. Objective: Our aim is to study the toxicity of the industrial chemical N-(2-aminoethyl) ethanolamine (AEEA) in the development of dissecting aortic aneurysm (DAA). Methods: Pregnant Sprague-Dawley rat dams were treated with AEEA by intraperitoneal (IP) injection or gavage on gestation days 14-20, a period of rapid aortic development. The aortas from newborn pups were harvested and the histology and pathology of aorta were examined. DAA were detected grossly and confirmed microscopically. The cytotoxicity of AEEA was determined by using the standard MTT measure of cellular viability. Results: The DAAs were detected in AEEA IP injection groups: 8/27 pups at 10 mg/kg, 19/29 pups at 25 mg/kg, and 7/9 pups at 50 mg/kg. In AEEA gavage groups, the DAAs were found in 8/27 pups at 10 mg/kg, 21/24 pups at 50 mg/kg, 26/26 pups at 100 mg/kg, and 38/38 pups at 150 mg/kg. An In vitro study showed that an approximately 50-60% decrease in viability at 25 mM AEEA or above. Conclusions: Our data indicate that AEEA given IP or by gavage results in the development of DAA. The incidence of DAA reaches 100% in live pups at the dose of 100 mg/kg via gavage of AEEA, but without lethality compared to IP treatment. This Work is Supported by Grant ES006676 from NIEHS.