Abstract:To study the rule of remodeling and the relationship between stress and growth of abdominal aorta in hypotension. Methods A hypotensive model was established in rats by constricting the abdominal aorta below the orifice of the left renal artery. The morphormetric parameters and microstructural components of the abdominal aorta was observed on the tissue slides of the artery in different phases. Results f Hypotension results in a negative increase of morphometric dimension of smooth muscle, collagenic fiber and elastic fiber. Conclusions: The decrease of the wall area occurred earlier than any other parameter, and its tendency of the changes is most stable, it's negative increase rate and total negative increase degree was the greatest at different phases, so the wall area is the characteristic guideline. Among the three microstructural components, Smooth muscle was the most sensitive to stress, it's total negative increase degree was the greatest, it was the important factor of arterial remodeling.