Comparisons Of The Expression Of PECAM-1between Different Arteries And Its Relationship With Atherosclerosis In Rabbits

Objective:To compare the progress of atherosclerosis and the expression of platelet endothelial cell adhesion factor-1(PECAM-1) between different arteries of rabbits and investigate the role of PECAM-1in atherosclerosis.Methods:After2weeks’ adaptive feed, thirty-three healthy New Zealand white rabbits were randomly divided into control group (n=10) and high fat group (n=23),respectively fed with ordinary and high cholesterol diet(both100g/d). All the rabbits were taken venous blood for the determination of plasma triglyceride, cholesterol, low density lipoprotein, high-density lipoprotein levels at6th,10th,14th week after diet feeding. One of the animals in the high fat group was chosen randomly to be narcotized and executed after fed for6th weeks,10th weeks,14th weeks. Aortic tissues were removed from the ascending aorta to test whether the rabbits were suffering atherosclerosis. After the success of the model building was determined, all the rabbits were narcotized and executed after fed for14th weeks. Internal mammary artery and coronary artery were separated. The pathological tissues were prepared for HE staining and immunohistochemstry to analyze the development of the atherosclerosis plaques and the expression of PECAM-1in abnormal arteries and atherosclerotic plaques. Frozen tissues were applied to Western blotting for semi-quantifying the expression of PECAM-1.Results:1. Compared with control group, plasma cholesterol and LDL levels of high fat group were obviously higher (all P<0.05). There was gradually formed atherosclerotic plaque. At the14th week obviously atherosclerotic lesions were found in aortic artery walls. 2. HE staining results of coronary artery and internal mammary artery showed that in control group both the two vessels had clear vascular structure and smooth intimal. Coronary artery in the high fat group had atherosclerosis plaque lesion. There was only intimal thickening in internal mammary artery.3. PEC AM-1expressed obviously in the whole inner membrance of the two arteries in control group. There was a decline of the expression of PECAM-1in the high fat group. Western blotting was used to semi-quantify the expression of PECAM-1.Compared with control group, the expression of PECAM-1of the two arteries in high fat group was both significantly reduced ((P<0.05).4. Western blotting was used to semi-quantify the expression of PECAM-1. The results showed that in control group the expression in the internal mammary artery was higher than coronary artery. The high fat group was just the opposite. But unfortunately they both had no significance (P>0.05).Conelus i on:1. The using of high cholesterol diet can successfully establish a rabbit animal model of atherosclerosis.2. There is difference in the progress of atherosclerosis between the internal mammary artery and coronary artery.3. As the development of atherosclerotic plaques, the expression of PECAM-1is decreasing. It is speculated the PECAM-1plays an important role in plaque formation.4. The expression of PECAM-1between different arteries has no statistical significance. It is supposed that PECAM-1has no relationship with atherosclerosis susceptibility.