富硒麦芽对二乙基亚硝胺诱发大鼠肝癌血管生成的影响

试验选择雄性SD大鼠100只，体重100~120 g，随机分成3组。试验Ⅰ组日粮中添加富硒麦芽（SEM）使硒含量达到3.0 mg/kg；试验Ⅱ组为模型组；试验Ⅲ组为阴性对照组，不诱癌不加SEM；试验Ⅱ、Ⅲ日粮中分别添加亚硒酸钠使硒含量达到0.1 mg/kg。试验Ⅰ、Ⅱ组饮水中添加100 mg/L二乙基亚硝胺（diethylnitrosamine，DEN）诱癌，维持DEN摄入量每天约10 mg/kg体重，连续16周，然后改饮普通灭菌水至18周末。试验Ⅲ组始终以普通灭菌水自由饮用。18周末，处死大鼠。利用免疫组织化学法分析大鼠肝肿瘤微血管密度（microvessel density，MVD）和血管内皮生长因子（VEGF）的表达。结果表明，SEM组MVD和VEGF表达较模型组显著降低。因此，表明SEM对肝肿瘤血管生成有抑制作用，下调VEGF表达可能是其抑制肿瘤血管生成的主要机理之一。

Effect of Selenium-enriched Malt on Angiogenesis in the Rat Hepatoma Induced by Diethylnitrosamine

100 SD rats weighting 100～120 g were divided randomly into 3 groups. The animals in groupⅠwere fed with 3.0 mg/kg selenium as Se-enriched malt (SEM) supplemented diets. Animals in groupⅡand groupⅢreceived 0.1 mg/kg selenium in sodium selenite only and were severed as the positive control and negative control respectively. Animals groupⅠand groupⅡwere induced hepatoma by diethylnitrosamine resolved 〖JP+3〗with sterilized water (100 mg/L) at the dosage of 10 mg/kg body weight every day for 16 weeks，then drank with sterilized water for another 2 weeks. At 18th week，the rats were killed. Microvascular density (MVD) and.vascular endothelial growth factor (VEGF) protein level in tumor tissue were determined by immunohistochemistry. The results indicated that MVD and VEGF protein levels in the SEM group were significantly lower than those in the model group (P<0.05). It demonstrated that SEM could inhibit angiogenesis in the rat hepatoma. The down-regulating of VEGF expression might be involved in the angiogenesis inhibition.