Rainey J B, Davies P W, Williamson R C
Br J Cancer. 1987 Mar;55(3):265-8. doi: 10.1038/bjc.1987.51.
Postoperative hyperplasia enhances experimental intestinal carcinogenesis, but the effects of nonsurgical adaptation are uncertain. The tropic and tumour-promoting potentials of moderate hypothermia were tested in two groups of male Sprague-Dawley rats housed at 10 degrees C for 30 weeks. One group (n = 10) received a 6-week course of azoxymethane (total dose 90 mg kg-1). The second group (n = 7) acted as hypothermic controls. Another 2 groups maintained at 22 degrees C received azoxymethane (n = 15) or served as normothermic controls (n = 15). Overall food intake was 42% higher in the hypothermic groups, yet at sacrifice mean body weight was 13% lower (P less than 0.01). Hypothermia and azoxymethane combined to produce the following increases in crypt cell production rate (CCPR), as determined stathmokinetically: duodenum 170%, jejunum 172%, ileum 74%, proximal colon 227% (P = 0.05-0.01). Independently hypothermia had no effect, but azoxymethane produced 76-156% increases in CCPR throughout the large intestine. Although hypothermia did not affect overall tumour yield, the mean diameter of proximal colonic tumours was increased by 65% (P less than 0.05). In rats receiving azoxymethane, hypothermia stimulates cell proliferation in the small bowel as well as in the proximal colon, where it has a correspondingly mild cocarcinogenic effect.
术后增生会增强实验性肠道致癌作用，但非手术适应性的影响尚不确定。在两组饲养于10摄氏度环境中30周的雄性斯普拉格-道利大鼠中测试了中度低温的促生长和促肿瘤潜力。一组（n = 10）接受为期6周的偶氮甲烷疗程（总剂量90毫克/千克）。第二组（n = 7）作为低温对照组。另外两组饲养于22摄氏度环境中，分别接受偶氮甲烷（n = 15）或作为常温对照组（n = 15）。低温组的总体食物摄入量高出42%，但在处死时平均体重低13%（P < 0.01）。低温与偶氮甲烷联合作用使隐窝细胞产生率（CCPR）出现以下升高，通过静止分析法测定：十二指肠升高170%，空肠升高172%，回肠升高74%，近端结肠升高227%（P = 0.05 - 0.01）。单独的低温没有影响，但偶氮甲烷使整个大肠的CCPR升高76 - 156%。尽管低温不影响总体肿瘤产量，但近端结肠肿瘤的平均直径增加了65%（P < 0.05）。在接受偶氮甲烷的大鼠中，低温刺激小肠以及近端结肠中的细胞增殖，在近端结肠中它具有相应的轻度促癌作用。
