一种新的与细胞分化相关的基因在不同组织及细胞系中表达与定位

为改进胃癌模型的制作,在高盐饲料条件下,比较了小剂量甲基硝基亚硝基胍(MNNG)持续给药及高剂量灌胃在诱发大鼠胃癌的类型、造模周期及成功率上的差异。将66只大鼠随机分三组,1组给予含盐8％的高盐饲料20周,其中前17周同时自由饮用添加100 mg/LMNNG的消毒自来水;2组先给予正常饮食饮水,于造模第1和第14天按200 mg/kg给予MNNG灌胃,然后在灌胃第3天起予每周用饱和氯化钠灌胃两次持续三周共6次,第4周起给予高盐饲料,正常饮水直至20周末;1、2组均于第21周起改为正常饮食饮水,第35周末处死取材,其中1组在第20周时取10只处死取材;3组大鼠给予正常饮食,35周一并处死。所有标本常规制石蜡切片HE染色。结果显示,高盐饲料加小剂量MNNG持续给药能较特异地诱导大鼠胃腺癌,诱癌周期短,仅35周,诱癌成功率高达90％,肿瘤多位于胃窦小弯侧及幽门部,大剂量MNNG灌胃加高盐饲料可较特异地诱发大鼠前胃鳞癌,诱癌率为68.4％。因此高盐饲料配合小剂量持续给药是较好的诱导胃腺癌的造模方法。

Expression and Location of a Novel Gene with Cell Differentiation in Different Tissues and Cell Lines

To study the difference between high dose sodium-chloride diet associate with high dose N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) gavage or low dose MNNG in drinking water in inducing gastric carcinomas in rats. Sixty-six male 6-week-old Wistar rats were divide into 3 groups. Group 1 rats were given MNNG in drinking water at a concentration of 100 mg/L for 17 weeks and were simultaneously fed a diet supplemented with 8% NaC1 for 20 weeks. Group 2 rats were initially given MNNG (200 mg/kg b. w. ) by gavage at days 0 and 14 as well as saturated sodium chloride solution (S-NaCl, 1 ml per rat) every 3 days during first 3 weeks (six times) , and then treat with high dose of sodium-chloride diet for 17 weeks. Then these two groups of rats were treated with normal diet for 15 weeks. Group 3 rats were fed on normal diet for 35 weeks. At week 20, ten rats of group 1 were killed and at the end of week 35 all surviving animals were killed. All the specimens were histopathologically investigated. The result showed that the incidence of glandular stomach adenocarcinoma in group 1 was 20% in week 20 and in week 35 was 90%. The incidence of forestomach cancer in group 2 was 68. 4%. These data indicated that the method of high dose sodium-chloride diet associate with low dose MNNG in drinking water is more effective in inducing glandular stomach adenocarcinoma.