Proliferation and C-myc Gene Expression of Smooth Muscle Cells in Rabbit Carotid Artery after Stenting

<正> Objectives To investigate theproliferation of smooth muscle cells (VSMCs) and theexpression of c-myc gene in rabbit carotid arieries af-ter stenting. Methods Platinium-Iridium stent wereimplanted into the right carotid arteries of 16 rabbitsunder vision. 7,14,30 and 90 days after the stentingprocedure, morphological changes of VSMCs were ob-served under light and transmission electron micro-scope. The c-myc gene expression was detected by insitu hybridization (ISH) and immunohistochemicalstaining. Results 7 days afer stenting, the pheno-type of VSMCs changed from contractile to syntheticphenotype; there were a number of proliferative VSM-Cs in the neointima. At 14 and 30 days, there weresynthetic and transitive VSMCs. At 90 days, the phe-notype of VSMCs recovered to contractile phenotype.The ultrastructure of typical synthetic phenotype ofVSMCs were round, containing a large amount ofrough endoplasmic reticulum and mitochondria. C-myc expression were positive both by ISH and im-munohistochemical stainin