核黄素对受冷大鼠增重、成活和有关激素的影响

方法：低温下（１０℃±２℃）饲养的大鼠仔鼠补充核黄素至６０日龄连续暴露７２小时后采血并摘取肾上腺，结果：１．各试验组和适温对照组成活率高，而低温对照组低。２．试验组增重效果优于对照组。３．试验组大鼠肾上腺皮质束状带宽度、细胞个数、髓质细胞数与适温对照组比较差异显著（Ｐ＜０．０１）。试验Ⅲ组束状带细胞个数与低温对照组之间差异显著（Ｐ＜０．０５）。４．各试验组的血清皮质醇（Ｃｏｒｔ）、Ｔ３、Ｔ４水平较低温对照组低；各试验组的生长激素（ＧＨ）水平虽较低温对照组稍高，但无显著性（Ｐ＞０．０５）；试验组的胰岛素（Ｉｎｓ）水平较两对照组高。提示日粮添加核黄素可以促进机体的冷适应，而且也有助于机体耐寒力的提高

EFFECTS OF RIBOFLAVIN ON WEIGHT GAIN,SURVIVAL AND RELEVANT HORMONES OF RATS DURING COLD EXPOSURE

Fifty-nine newborn(7 litters)rats were divided randomly into seven groups to evaluate the effects of riboflavin on weight gain,survival and relevant hormones during cold exposed.The experimental groups from Ⅰ to Ⅴ were received intraperitoneal injection(ip) riboflavin of 1.5,4.0,6.0,7.5 and 9.0mg/kg body weight(BW) respectively at 4 day intervals until d 30 at air temperature of 10±2℃.The control groups Ⅵ,Ⅶ were received ip 0.9% NaCl at air temperature of 20±2℃ and 10±2℃ respectively.The experimental group Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ were supplemented with 1.5,4.0,6.0,7.5,9.0mg of VB 2 per kg diet after d 30(weaning) until the end of experiment.The rats at d 61 were placed into another room,and exposed to air temperature of 2±2℃ for 72h,feed and water ad lib.The results revealed that supplementation of riboflavin to cold exposed rats could raise survival rate,increase BW.The thickness of fascicular zone and cell count of adrenal cortex,cell count of adrenal medulla of experimental groups were significantly higher (P<0.01) than that of Ⅵ(normal control).The cell count of fascicular zone of Ⅲ group was higher(P<0.05)than that of the Ⅶ group (cold exposure control).The serum cortisol, T 3,T 4 levels of experimental groups were lower than that of Ⅶ group and the serum GH levels of experimental groups were somewhat higher than that of Ⅶ group.But these changes were not statistically significant (P>0.05).The insulin levels of experimental groups were higher than that of the two control groups.These results suggested that riboflavin could promote cold acclimatization for rat.