^(125)I支架抑制犬胆管损伤后胆管平滑肌细胞增殖的作用

^(125)I stenting inhibits proliferation of smooth muscle cells in dogs after bile duct injury

目的探讨125I支架抑制犬胆管损伤后胆管平滑肌细胞增殖,预防胆管再狭窄的可行性。方法实验犬12只(体质量15~18kg),随机分为普通支架组和125I支架组各6只。用切断吻合法,造成胆总管损伤。术后30d胆道狭窄形成后,分组将普通支架及125I支架从胆总管末端开口处释放到胆总管内。置入支架后60d分别行病理形态学检测,用免疫组织化学方法测定P53蛋白、增殖细胞核抗原(proliferatingcellnuclearantigen)及平滑肌肌动蛋白(smoothmuscleac-tin),并测定外周血和支架周围放射性。结果支架置入后60d,与普通支架组比较,125I支架组胆管最大内膜厚度显著减少(P<0.05),两组胆管狭窄面积百分比分别为(53.72±13.89)%和(17.34±9.28)%,差异有显著性(P<0.05),125I支架组胆管腔周长及胆管腔面积均较普通支架组明显增加(P<0.05),125I支架组胆管平滑肌增殖细胞核抗原(PCNA)及平滑肌肌动蛋白(SMA)表达较弱,而P53蛋白表达增高,后者平滑肌PCNA及SMA表达增高,而P53蛋白表达较弱。结论125I支架照射可抑制平滑肌细胞增殖,预防胆管再狭窄。

Objective To explore the feasibility of preventing bile duct restenosis with the stent treated with ^125I and to elucidate the mechanisms of the inhibition of the smooth muscle cell proliteratlon and the increase of apoptosis after bile duct injury in dogs. Methods The experimental dogs were randomly divided into common stent group and ^125I stent group, each of 6 animals. Duct was injured with cutting anastomosis. After formation of duct stenosis 90 d post operation, common stents and ^125I stems were inserted in the end of the bile common duct of the 2 groups respectively. Morphological study on the duct, immunohistochemistry for P53, proliferating cell nuclear antigen （PCNA） and smooth muscle actin （SMA）, the radiation of the peripheral blood and tissue around the stent were studied. Results The utmost intimal thickness of bile duct was found to be obviously less in the ^125I stent group compared to in common stent group after 90 d, and the percentages of the stenosis of the bile duct were （ 53.72±13.89） % and （ 17.34±9.28 ） %, respectively （ P 〈 0.05 ）. The circumference and area of bile duct lumen were obviously larger compared to that in the common stent group （P 〈 0.05 ）. The expressions of PCNA and SMA in biliary smooth muscle ceils were weaker in ^125I group than in the common group, and that of P53 was obviously up-regulated. Conclusion ^125I stent may inhibit the prolif-eration of smooth muscle ceils and prevent the restenosis of bile duct.