Abstract

To investigate the effect of losartan on vascular remodeling and transforming growth factor-beta and phosphoinositide 3-kinase/protein kinase B pathway. 30 pregnant rats on the 14th d were selected, 20 of which were given hydroxyethyl ethylene diamine 150 mg/kg/d by gavage to induce aortic dissection. They were randomly divided into losartan group, which was given losartan 20 mg/kg/d by gavage, model group, gavaged with the same amount of normal saline, and 10 normal newborn rats were given the same amount of normal saline by gavage as normal group. Hematoxylin and eosin staining was used to measure the thickness and diameter ratio of the aortic media of mice in each group, Masson staining was used to observe the content of collagen fibers in the aorta of mice in each group, elastic fibers in the aorta of mice in each group were stained, and transforming growth factor-beta and phosphoinositide 3-kinase/protein kinase B pathway protein expression. The diameter of aortic lumen in losartan group was reduced than that in model group, and the ratio of the thickness of the middle membrane and the diameter of the aorta in losartan group was raised than that in model group (p<0.05). The contents of elastic fibers and collagen fibers in the aorta of losartan group were raised than those in the model group (p<0.05). The transforming growth factor-beta 1 protein content in the losartan group rats was reduced than that in the model group (p<0.01). The content of protein kinase B protein in the aortic vessels of losartan group was reduced than that of the model group, and phosphorylatedprotein kinase B protein was raised than that of the model group (p<0.01). Losartan has protective effect on aortic wall of rats with aortic dissection, and the mechanism may be through inhibiting transforming growth factor-beta 1 pathway, which activates downstream phosphoinositide 3-kinase/protein kinase B pathway related proteins, and then inhibits the expansion and progression of aortic dissection.