Effects of chitosan on atherosclerosis plaques in rats

Objective:To observe the effects and mechanisms of chitosan on atherosclerosis plaques in rats.Methods:All the 40 Winstar rats were divided into four groups:group A:the rats were fed with normal diet,group B:the rats were fed with only high-cholesterol diet(no vitamin D3),group C:the rats were treated with one intramuscularly injection of vitamin D3(300 000 U/kg) and were denudated of endothelium,followed by high-cholesterol diet,group D:the rats were treated with 5% chitosan added into the diet besides treatment as group C.Ninety days later,the formation of atherosclerosis plaques and the activities of nitric oxide synthase in aortas in the four group rats were investigated.Results:After 90 days,(1)The aorta structure of rats fed with only high-cholesterol diet(no vitamin D3) was normal.Distinct atherosclerosis plaques were formed in the thoracic aortas of rats in group C,structure of aortas in group D was almost normal;(2)Compared with rats in group A,rats in group B,group C and group D had lower activities of endothelial nitric oxide synthase(P0.01),there was no differences among later three groups;(3)With inducible nitric oxide synthase(iNOS),there was no differences between group A and group B;whereas the activities of that of rats in group C were more higher than that of group A and B(P0.01);compared with group C,iNOS decreased in group D,but it was still more than that of group A,group B and C(P0.01);(4)Compared with group A,the levels of TC,TG,LDL-C increased(P0.05~0.01) in group B and C;compared with group C,the levels of TC,TG,LDL-C significantly decreased(P0.05~0.01) in group D;compared with group A,the HDL-C level of group B and C decreased(P0.01).Conclusion:Chitosan has role of anti-atherosclerosis through restraining absorb of cholesterol and triglyceride,and has indirect influence on NOS via role on serum cholesterol and triglyceride.