Atherosclerosis Model Induced By Compound Factors Of High-fat Diet/carotid Artery Injury In Rats

Purpose:We established a comprehensive animal model of experimental atherosclerosis,which is simple,inexpensive,and has typical pathological changes,was through a combina-tion of a high-fat diet,injection of vitamin D₂,and carotid electric shock injury.In order to explore the establishment of atherosclerosis model in rats,to provide a better and more conve-nient model for future Atherosclerosis medication.Method:192 clean male SD rats were randomly divided into six groups:normal group,sham operation group,clamp group,electric shock group 1?0.6 mA,5 min?,electric shock group 2?1 mA,5 min?,and electric shock group 3?1.4 mA,5min?,32 in each group.One week after adaptive feeding,the normal group continued to be fed with common feed.The other five groups were given a high-fat diet and intraperitoneal injection of vitamin D₂.In the sham-operated group,only the left carotid artery was dissected and electrical stimulation and clamping were not performed.After the clamp group was separated from the left carotid artery,it was clamped with a clamp for 20 minutes.In the electric shock group 1,the left carotid artery was shocked with 0.6mA and 5min,in the electric shock group 2,the left carotid artery was stimulated with 1 mA for 5 min,and the left carotid artery was stimulated with the electric shock 3 group with 1.4 mA and 5 min.Materials were taken at 4,6,8 and 12 weeks.Carotid artery HE staining and ELISA method were used to determine the indexes of rat TC,TG,HDL-C,and LDL-C.The obtained data were analyzed with SPSS19.0 software.Results:?1?A total of 11 rats died in the experiment,including 1 in the sham group,2 in the clamp group,1 in the electric shock group 1,1 in the electric shock group 2,and 6 in the electric shock group 3.The reason why 5 rats were mainly concentrated in 1-2 weeks after surgery may be due to the poor resistance and infection of rats after anorexia and surgery.The other 6 reasons for considering the cause of death may be the weight loss of rats in the late experimental period plus vitamin D₂ injection at 6 and 9 weeks.?2?Body weight changes:Rats in the normal group continued to gain weight and increased steadily.After 12 weeks,the average body weight reached 486.21±17.25 g.The weight gain of the other five groups was relatively fast in the early period,and the weight in the middle four weeks was relatively stable,with no significant changes.Both have declined.The average weight of the sham-operated group was 263.75±15.37 g after 12 weeks;the average weight of the clamp group was 260.23±12.35 g after 12 weeks;the average body weight of the electric shock 1group was 267.48±9.72 g after 12 weeks;the average body weight after 12 weeks of the electric shock 2 group.It was 258.63±11.41 g;the average body weight of the 3 groups after electric shock was 255.33±7.35 g after 12 weeks.?3?Lipid detection results:From the 4th week of the experiment,serum TC,TG and LDL-C in sham group,clamp group,electric shock group 1,electric shock group 2 and electric shock group 3 were significantly higher than those in normal group?P<0.05?.HDL-C was significantly lower than the normal group?P<0.05?.?4?Pathological changes:In the normal group,the carotid artery lumen was rounded,the intima-media adventitia was clearly demarcated,the structure of the endothelial cells was intact,and the internal elastic plate had no rupture.The media can be seen interspersed with fusiform or oval smooth muscle cells and wavy elastic membranes.A small amount of loose connective tissue can be seen on the outer membrane.In the sham-operated group,compared with the normal group,the intima of the vessel wall was thicker,the smooth muscle cells in the subendothelium were proliferated,the thickness of the media was thin,and the smooth muscle cells in the media decreased to the intima.In the clamp group,the carotid endothelium was detached,the intima was thickened,and it protruded to the lumen.A large number of smooth muscle cells proliferated and migrated to the intima,the foam cells were deposited,some of them were calcified,and the smooth muscle cells were arranged disorderly.A lot of inflammatory cell infiltration.The electric shock group 1 underwent microscopic observation of intimal thickening and foam cell deposition,disordered arrangement of elastic fibers in the media,and thinning of the media.The electric shock group 2 can see that the arterial endothelial cells fall off,a large number of smooth muscle cells migrate to the subendocardial,and the blood vessel wall protrudes into the lumen to form a plaque.The plaque contains foam cells,smooth muscle cells,and cholesterol crystals.Thrombus formation can be seen in the lumen,atrophy of the tunica media,narrowing of the lumen,and typical pathological changes in atherosclerosis.The thickening of the intima was obvious in the electric shock group 3.There was a lot of foam cells,the structure of the media was disordered,some of the walls were thickened,some of the walls were incomplete,and there were thrombi in the lumen.Conclusion:1.The atherosclerosis model can be established by high fat diet,vitamin D₂load and carotid artery electric shock injury.2.The group with 1mA,5min electric shock shows carotid artery intima damage,which is the optimum state in model making.