Study on vascular calcification and the expression of osteopontin and osteocalcin in vascular wall of aged rats

  Objective: To study the occurrence of vascular calcification in aged rats and the changes in the expression of osteopontin (OPN) and osteocalcin (OC) in the arterial walls of aged rats.

  Method: 20 SD rats aged 20 months were selected as the experimental group, and 20 SD rats aged 3 months were selected as the control group. Aortic strips, heart and kidney tissues of the rats were taken for examination. HE staining was used to observe the vascular morphology, Von Kossa staining to determine the degree of calcium salt deposition, and immunohistochemistry and Western-blot methods to determine the expression of OPN and OC in the blood vessel wall.

  Result: The vascular smooth muscle cells of the experimental group are arranged disorderly, the thickness of the media layer increases, the elastic plate is broken, and the degree of vascular fibrosis is increased; the endothelial cells and vascular smooth muscle cells of the control group are arranged neatly and the elastic plate is intact. Calcium deposits were seen in the large and small arteries of rats in the experimental group, and no calcium deposits were seen in the arteries of the control group. The expressions of OPN and OC in the vascular wall of the experimental group were significantly up-regulated compared with the control group (P<0.05).

  Conclusion: Vascular media calcification may be a pathological manifestation of vascular aging, and the formation of vascular calcification may be related to the up-regulation of bone formation-related proteins OPN and OC.