ABSTRACT
The aim of the present study was to clarify if old N-MRI rat, a strain which is easily available in Iran and cheap to maintain, is a suitable alternative to those previously reported. In this model, we compared three quantifiable parameters between old and young rats: biochemically, involving measurement of differences in the lipid profile. Histologically, the differences of the thickness of the wall of the aorta, the apparent degree of splitting within the aortic media, and the formation of foamy lipid layers on the outermost layer of the aorta. Pharmacologically, in vitro contractile responses/mg wet tissue weight to submaximal concentration of phenylephrine [1 micro M] and the rate of relaxation min-1 mg-1 tissue weight following administration of 0.1 mM of acetycholine. The proposed model was validated using lovastatin as test drug known for its lipid lowering and anti-atherosclerosis actions. The results showed that this model to be reliable, quantifiable and capable of detecting the effect of orally administered lovastatin. We recommend this model as an easy and accessible experimental model for various atheroscleorosis investigations