Magnetic Resonance Imaging
Magnetic Resonance Imaging (MRI) was used to evaluate the time-course
evolution of the aneurysm formation in response to Ang II. MRI
assessments were repeated every day for five days (0, 24, 48, 72 and 96
hours from the starting of Ang II infusion). The number of averaged
experiments (NA) was 2 and the total acquisition time for this
experiment was 12 minutes and 17 seconds. In the most caudal position of
the image volume a flow saturation slice was used to eliminate the
signal of venous flow. Magnetic Resonance Angiography (MRA) data were
processed using ImageJ 1.51 (NIH, Bethesda, Maryland, USA). The aorta
areas, comprising aortic wall and lumen, and the lumen areas were
measured by two independent observers using ParaVision 3.1 software
(Bruker, Ettlingen, Germany). Regions of interest were manually drawn
and the mean of the two measurements were calculated. The aortic areas
were measured on every 1-mm slice from the superior mesenteric artery to
10 mm above it.