The Study Of Vascular Smooth Muscle Cell's Replicative Senescence After Balloon Injury Of Rat Carotid Arteries

Objective By the study of vascular smooth muscle cell's replicative senescence after balloon injury of rat carotid arteries, to approach the role of replicative senescence in vascular restenosis, and provide a new theoretical basis of vascular restenosis.Methods 40 male wistar rats are randomly divided into two groups,one group 20 male wistar rats. The model of vascular restenosis established by balloon injury of rat carotid arteries are established.One group is experimental group(use neointima formation inhibitor),the other group is control group(don't use neointima formation inhibitor).Every group is divided into 5 subgroup,measure the PCNA-positive and SA-β-Gal-positive in 2d 1w 2w 4w 6w after the balloon injury.Result The positive rate of PCNA reach the max in the two weeks,then with the passage of time gradually decreased;when we use neointima formation inhibitor(All-Trans Retinoic Acid), Compared with the control group PCNA-positive rate has dropped.In the early days of balloon injury,the SA-β-Gal-positive rate is low, with the passage of time, SA-β-Gal positive rate gradually increased, Application of all-trans retinoic acid, compared with the experimental group, the SA-β-Gal positive rate was tend to decrease.Conclusion Vascular smooth muscle cell proliferation and replicative senescence are both existed after balloon injury of rat carotid arteries.In the different periods of injury, they play different roles on the formation of restenosis.Vascular smooth muscle cell proliferation play a major role in the early time,and there are mainly replicative senescences in the later time.When we use all-trans retinoic acid, neointima formation is inhibited,and the phenomenon of replicative senescences is tend to decrease.The phenomenon of replicative senescences maybe an important reason to oppose the restenosis.