Comparison of infrarenal and suprarenal sections of mouse ApoE-/- abdominal aorta

The ApoE -/- mice model of abdominal aortic aneurysm (AAA) involves introducing Angiotensin II subcutaneously to 14 week old male mice for 4 weeks by osmotic pump. A significant number of mice will develop aneurysm-like dilations in the suprarenal section of the abdominal aorta (SRA) that have a number of similarities to the human condition and make this a useful model of AAA. The mouse infrarenal aorta is very resistant to aneurysm formation while in humans AAA predominately occurs in the infrarenal section of the aorta (IRA). There have been a number of theories proposed to explain the site selctivity of aneurysm formation in AAA and this mice model. This study was designed to ascertain differences between SRA and IRA that may explain this site selectivity. Keywords: tissue type comparison The aortas of five groups of 2 male (14 weeks old) ApoE-/- mice were harvested and divided into infrarenal and suprarenal sections. RNA and proteins were extracted from each group of pooled segments to allow comparison between individual gene expression levels in IRA and SRA. The gene expression ratios of IRA to SRA were determined for each group and compared between groups.