补锌对缺锌大鼠烫伤后肠粘膜上皮细胞增殖的影响

The Influence of Zinc Supplements on the Proliferation of Gut Mucosa after Burns

目的探讨补锌对缺锌大鼠烫伤后肠粘膜上皮细胞增殖的影响。方法1个月龄大鼠饲予低锌饲料(含锌量:1.6μg/g)1周造成缺锌模型,20%深Ⅱ度烫伤后改饲3种不同含锌饲料(含锌量分别为:1.6、24.7、286.9μg/g)1周,同时设1组大鼠烫伤前后均饲予正常含锌饲料(含锌量:24.7μg/g)作为对照组。烫伤后第8天处死大鼠,留取标本。在动物处死前6h腹腔注射长春新碱(1mg/kg),计数肠腺细胞增殖率(CCRP)与标记指数(LI)用以反映肠粘膜增殖情况。结果各补锌组空肠CCPR、LI均高于缺锌组,回肠也存在类似的趋势。结论改善锌营养状态有利于烧伤后肠粘膜损伤的修复。

Objective To investigate the influence of zinc supplements on the prolifer at ion of gut mucosa after major burns.Methods Weanling rats were fed zinc-defic ient chows (zinc content:1.6ìg/g)for seven days to induce zinc deficient status.Twenty percent of each rat' s back was immersed in boiling water for 6seconds to make deeper second degree scalds on the eighth day.Then the rats w ere divided into three groups fed on chows different in zinc contents for7day s.Zinc contents were1.6,24.7,and286.9ìg/g respectively.A group of rats fed normal zinc content (24.7ìg/g)diets before and after scalds w as designed as control.Rats were killed on the8th day after burns and certain sections of jejunum and ileum were resected.Vincristine were injected(1mg /kg ,i.p.)6h before they were killed,which was supposed to block cell division in metaphase.According to morphological features,the number of divisive crypt cells blocked in metaphase as well as crypt cell production rate(CCPR)and l abeling index(LI)were calculated.Results CCPR and LI of zinc deficient grou p were the lowest among the four groups.CCPR and LI of jejunal mucosa were ma rkedly improved in the group of zinc supplements,in addition to jejunum,the sa me trend was also showed in ileac mucosa.Conclusions The nutritional status o f zinc play an important role on the proliferation of gut mucosal cells.To su pplement zinc after major burns could help to repair the damaged intestinal muc osa.