高机械指数超声造影对肿瘤肝转移影响的实验研究

摘要

Objective To observe the effects of high mechanical index ultrasound contrast on hepatic metastasis of colorectal cancer. Methods Hepatic metastasis models were established by injecting Lovo cells into the spleen of SD rats.This study was divided into control group, microbubble plus ultrasound radiation group simple contrast agent group and simple ultrasound radiation group.Ultrasound contrast agent SonoVue(1 ml/kg) was injected via tail vein, high mechanical index ultrasound contrast (frequency 1.5 MHz,MI 1.7) was performed intermittently for 2 min.After 10 d,the animals were killed and the size and number of hepatic metastasis were compared.Histological pathology and its ultrastructure were observed.Results There were no significant differences between contral group,simple ultrasound radiation group and simple contrast agent group in metastatic rate ( P＞0.05).There were no obvious differences between contral group, simple ultrasound radiation group and simple contrast agent group in cells'ultrastructure by transmission electron microscopy (TEM).The number and size of hepatic metastasis decreased obviously in microbabble plus ultrasound radiation group ( P＜0.01 ), the mitochondrion was swelling and the gaps of endothelial cells were loose. Conclusions High mechanical index ultrasound contrast can inhibit the hepatic metastasis of colorectal cancer.%目的 观察高机械指数超声造影对结肠癌肝转移的影响.方法 经大鼠脾注入结肠癌Lovo细胞,制备肝微小转移灶动物模型,分为对照组、微泡+超声辐照组、单纯超声辐照组和单纯微泡组.使用超声造影剂SonoVue(1 ml/kg),经大鼠尾静脉注射后,进行超声间歇辐照2 min(频率1.5 MHz,机械指数1.7),10 d后处死大鼠,观察肝转移肿瘤数目、大小、病理学改变及其超微结构的改变.结果 对照组、单纯辐照组及单纯微泡组之间的转移率差异无统计学意义(P＞0.05);透射电镜可见单纯辐照组及单纯微泡组肿瘤细胞核大,胞浆和胞核比例减小,线粒体较多,未见肿胀,与对照组无明显差异.而微泡+超声辐照组肿瘤的数目及大小明显低于对照组,差异有统计学意义(P＜0.01),肿瘤周围脾组织微血管有大量血栓形成;透射电镜可见肿瘤细胞线粒体明显肿胀,内皮细胞间缝隙连接增宽.结论 高机械指数超声造影对结肠癌肝转移有明显抑制作用.