营养支持途径对严重烧伤后肠黏膜上皮细胞增生的影响

Effects of nutrition route on proliferation of intestinal epithelial cells in severe burn injury

目的:探讨肠道喂养及静脉营养对严重烧伤早期肠黏膜上皮细胞增生功能的影响.方法:将30%TBSAⅢ度烧伤大鼠行颈外静脉插管后,随机分为肠道喂养组(EF组)及静脉营养组(PN组),伤后2h分别采用灌喂和颈外静脉输入方法给予等氮、等热卡的营养液.分别于伤前、伤后6,12,24,48和72h处死动物,检测肠黏膜蛋白质含量、胸腺嘧啶核苷激酶活性、增生指数及PCNA表达.结果:烧伤后两组大鼠肠黏膜蛋白质含量均降低,EF组在伤后24,48和72h分别为262±24mg/m,283±29mg/m,282±18mg/m,明显高于PN组的195±45mg/m,194±41mg/m,143±19mg/m.烧伤后肠黏膜胸腺嘧啶核苷激酶活性多较伤前降低,EF组在伤后72h明显高于PN组(分别为88±19nmol/m,35±7nmol/m).PN组肠黏膜细胞增生指数在伤后6,12h分别为78.4±3.4%,89.9±1.3%,明显高于EF组的60.4±10.1%,75.7±6.9%;而在伤后48,72h分别为25.9±12.7%,12.5±8.6%,显著低于EF组的78.9±1.6%,56.9±5.6%.EF组肠黏膜PCNA表达明显多于PN组.结论:早期肠道喂养较静脉营养更能促进严重烧伤后肠黏膜上皮细胞增生,利于受损肠黏膜的修复.

AIM:To investigate the effects of nutrition route on the pro-liferation of intestinal epithelial cells in severe burn injury.METHODS:Rats inflicted with 30 %TBSA Ⅲ dgree burnswere randomly divided into enteric feeding group (EF) andintravenous parenteral nutrition group (PN). To each animalof both groups, equal volume of nutritional support fluidcontaining predetermined amount of calories and nitrogenwas supplied at 2 hr postburn (PBH). Protein content, thy-midine kinase activity, proliferative index and PCNA expres-sion in the intestinal mucosa were analyzed at 0, 6, 12, 24,48, and 72 PBH respectively.RESULTS:Following burn injury, protein contents of the in-testinal mucosa decreased obviously in both groups. At 24,48 and 72 h postburn, mucosal protein contents in EF groupwere 262±24 mg/m, 283±29 mg/m, and 282±18 mg/mrespectively, significantly higher than those in PN group(195±45 mg/m, 194±41 mg/m, and 143±19 mg/m,respectively). Thymidine kinase activity of the intestinalmucosa in EF group was obviously higher than that in PNgroup at 72 h postburn (88±19 nmol/m vs 35±7 nmol/m).At 6 and 12 h postburn, proliferative index of the intestinalepithelial cells in PN group were 78.4±3.4 % and 89.9±1.3 %respectively, markedly higher than those in EF group(60.4±10.1 %, 75.7±6.9 %), but significantly lower thanthose in EF group at 48 and 72 h postburn (25.9±12.7 % vs78.9±1.6%) and 12.5±8.6 % vs 56.9±5.6 %). PCNA ex-pression in intestinal mucosa in EF group was higher thanthat in PN group.CONCLUSION:Enteric feeding is superior to parenteral nu- trition in promoting proliferation of the intestinal epithelialcells, which could be beneficial to the repair of damagedintestinal mucosa in severe burn injury.