Studies On Relationship Between Lysyl Oxidase Gene And Pathological Changes Of Atherosclerosis

Atherosclerosis (AS) is one of common diseases for hurting the people's health seriously. The incidence of AS rises up continuously by following the development of economy and improvement of living standard in China. The pathologic characteristics of AS is that blood-fat deposits in intima of artery to induce focal fibrous hyperplasia in intima,and necrosis,collapse in deep area and to form gruelled substance,so it make vascular wall turn sclerotic and lumen becomes stenosis. Lysyl oxidase (LO), an extracellualr copper amino oxidase, initiates the cross-linking of collagens and elastin by catalyzing oxidative deamination of the ε-amino group in certain lysine and hydroxylysine residues. Lysyl oxidase gene (LOX) plays an important role in the synthesis of connective tissue stroma by cross-linking of collagen and elastin in extracellular matrix. The studies about LOX were principally focused on its biochemical characteristics and cross-linking activities toward collagen and elastin substrates.Using the autopsy specimen of AS in Yanbian and LOX antibody, it was observed and studied that the expression, distribution and biological activities of LOX in smooth muscle cells, collagen and elastin of atheromatous vascular wall and the relationship betweenLOX and pathological changes of AS by immunohistochemistry (avidin-biotin-complex peroxidase method, ABC method), Van Gieson stain, Verhoeff stain and HE stain in order to provide necessary theoretical basis and practice significant for prevention and cure of AS.The experiment results showed that there were obviously proliferated smooth muscle cells and transformed foam cells in arterial wall of AS. The cumulus bulge in intima of atheromatous plaque was protruded to lumen and covered with fibrous connective tissue. It was seen by the Van Gieson stain and Verhoeff stain that the proliferated collagens and elastin as well as the separated elastic lamina. The expression of LOX in atheromatous plaques was seen by immunohistochemistry stain. Total positive rate of LOX was 68.6%, in which 31.4% was -, 31.4% was +, 20.0% was ++ and 17.1% was +++, respectively.The experiment results indicate that LOX plays some role in the development of AS and the regulation of LOX productions and activities play a key role in maintaining the structural integrity of extracellular matrix furthermore. The results indicate that: ① there are some degree expressions of LOX in arterial wall of AS; ② abnormal LOX activities may contribute to the pathogenesis of AS by remodeling the extracellular matrix that it is interrelated closely with the functions of LO family; ③ LOX activities of vessel wall is increased at AS.