The role of beta irradiation on neointimal formation and apoptosis in vein grafts model / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the effect of beta irradiation on intimal proliferation and apoptosis in vein grafts.</p><p><b>METHODS</b>Autogenous vein graft model was established in 80 rats by transplanting the internal branch of the jugular vein to the carotid artery by end to end anastomosis. The veins were irradiated by (32)P solution before anastomosis. Two dose schedules were studied: control group (graft, nonirradiated) and radiation group (20 Gy). The grafted veins were harvested at 3, 1, 2 and 4 week respectively after the operation. intimal hyperplasia (IH), smooth muscle cell (SMC), proliferation, p53, bcl-2 and bax were observed pathologically and immunohistochemically. They were analyzed by a computerized system. The presence of apoptotic VSMC was demonstrated by TUNEL method.</p><p><b>RESULT</b>There was a significant decrease in the average intimal thickness at 7, 14 and 28 days (t = 15.694, P < 0.05) in the radiation group. Immunohistochemical analysis of PCNA indicated decreased positive cells in the radiation group compared with the controls at 1 and 2 weeks (t = 60.157, P < 0.01). Apoptosis of VSMC was higher in the radiation group than in the control group at 2 weeks (t = 56.176, P < 0.01). There was no significant difference in expression of P(53) between the two groups, and there was a significant increase in bax/bcl-2 in the radiation group at 2 weeks (t = 9.783, P < 0.05).</p><p><b>CONCLUSION</b>These preliminary results demonstrated that low dose of beta irradiation in the vein graft inhibits SMC proliferation and induces the apoptosis of VSMC in rats.</p>

The effect of p27~(kip1) gene transfection mediated by PLGA nanoparticles on neointimal proliferation and apoptosis in rats vein grafts / 中国普通外科杂志

Objective To investigate whether human p27kip1 gene transfection mediated by nanoparticles( NP) can express p27kip1 protein and inhibit the neointimal formation in rat vein grafting models. Method Autogenous vein graft model was established in 120 Wistar rats by transplanting internal branch of jugular vein to carotid artery. Rats were divided into three groups: (1) p27 group; p27kip1 gene mediated by NP were transfected into the veins before anastomosis; (2) control group; the veins were transfected by simple NP; (3) grafting group;the veins were grafted without transfection. The grafted veins were harvested at 3 d, 7 d, 14 d and 28 d respectively after the operation. The exogenous p27 kip1 protein expression in veins was determined by Western blot. Intimal hyperplasia (IH) and PCNA were observed by pathology and analyzed by computer digitizing system. The presence of apoptotic VSMC was demonstrated by TUNEL method. Result p27kip1 gene transfection mediated by NP complex increased protein expression of p27kip1 gene and there was a significant decrease in the intimal average thickness at 7 d, 14 d and 28 d in p27 group (P

Expression of transforming growth factor-?1 and its type Ⅰ receptor in autogenous vein grafts in rats / 中国普通外科杂志

ObjectiveTo investigate the expression of TGF ?1 and type Ⅰ receptor and their relations with intimal hyperplasia in autogenous vein grafts in rats. Methods Autogenous vein graft model was established in 48 Wistar rats. The vein grafts were harvested on day 3, 7, 14, and 28.Histomorphological methods were used to measure the thickness of intima and wall at different time points. Immunohistochemistry and Western blot were used to detect the protein expression of TGF ?1 and TGF ?RⅠ . RT PCR was used to detect their mRNA level. ResultsThe intimal thickness increased on day 7 compared with controls( P