卡巴胆碱复合膳食纤维对颅脑损伤后大鼠肠机械屏障保护作用的研究

Effect of carbachol combined with dietary fiber on intestinal mucosal barrier after diffuse brain injury in rats

目的探讨早期灌胃给予卡巴胆碱复合膳食纤维对弥漫性颅脑损伤后大鼠肠黏膜机械屏障的影响。方法采用Marmarou模型制备方法造成成年雄性Wistar大鼠弥漫性颅脑损伤,造模后成活的大鼠随机分为4个实验组：生理盐水组（NS组,n=32）、卡巴胆碱组（CAR组,n=32）、膳食纤维组（DF组,n=32）、卡巴胆碱复合膳食纤维组（CAR＋DF组,n=32）。另设只切开头皮的假手术组（对照组,n=20）。对照组自由饮水,实验组从造模成功后2 h开始灌胃,分别给予生理盐水、卡巴胆碱（100μg·kg^-1·12h^-1）、膳食纤维（8g·kg^-1·d^-1）、卡巴胆碱＋膳食纤维,于伤后6、12、24、48 h活杀取材,检测血浆中二胺氧化酶（diamine oxidase,DAO）活性、D-乳酸含量,并观察小肠绒毛病理学改变。结果成功制备弥漫性颅脑损伤大鼠模型,弥漫性颅脑损伤后大鼠肠黏膜固有层水肿,炎性细胞浸润,部分黏膜上皮细胞变性、坏死、脱落,绒毛变短,在12 h损伤最重。CAR组、DF组及CAR＋DF组肠绒毛较NS组恢复快,表现为炎症、水肿减轻,肠绒毛高度增加,并且血浆中DAO活性及D-乳酸含量低于NS组,但至伤后48 h均并未恢复至对照组水平。CAR组、DF组与CAR＋DF组比较,除6 h CAR组D-乳酸含量较CAR＋DF组低且差异有统计学意义（P〈0.05）外,CAR组、DF组及CAR＋DF组6～48 h DAO活性、D-乳酸含量及肠绒毛高度均无统计学差异（P均〉0.05）。结论弥漫性颅脑损伤后早期灌胃给予卡巴胆碱、膳食纤维、卡巴胆碱复合膳食纤维可减轻肠黏膜损伤,保护肠黏膜机械屏障,但本实验中卡巴胆碱复合膳食纤维与单药应用比较并未显现出明显优势。

Objective To investigate the effect of the early gavage administration of carbachol combined with dietary fiber on intestinal mucosal barrier after diffuse brain injury（ DBI） in rats. Methods The DBI model of male adult Wistar rat was established by Marmarou＇s method. The survived rats after molding were randomly divided into four experimental groups：normal saline group（ NS group,n = 32）,carbachol group（ CAR group,n = 32）,dietary fiber group（ DF group,n = 32） and carbachol combined with dietary fiber group（ CAR ＋ DF group,n = 32）. In addition,a sham operation group（ cut the scalp only）（ control group,n = 20） was designed. The drinking water was freely given in control group. The gavage was administered 2 hours after successful modling in different experimental groups. Carbachol（ 100 μg·kg^-1·12 h^-1）,dietary fiber（ 8 g·kg^-1·d^-1） and carbachol plus dietary fiber were respectively given in CAR group,DF group and CAR ＋ DF group. The experimental rats were killed when alive at 6-,12-,24-and 48-hour after the DBI,and the samples were acquired. The activity of plasma diamine oxidase（ DAO） and the content of plasma D-lactate were detected,and the pathological changes of intestinal villi were observed. Results The rat model of DBI was established successfully. After DBI,edema of intestinal mucosal lamina propria,infiltration of inflammatory cells,degeneration,necrosis and fall of partial mucosa epithelial cells,shortened intestinal villi were the most serious at 12-hour. Compared with NS group,the intestinal villi were quickly recovered with alleviated inflammation and edema,heighten intestinal villus,and the activity of plasma DAO and content of D-lactate in CAR group,DF group and CAR ＋ DF group decreased,but they were all not recovered to the levels of control group at 48-hour after injury. In addition to D-lactate content at 6-hour in CAR group was significantly lower than that in CAR ＋ DF group（ P〈0. 05）,there were no statistical differences in the activity of DAO,content of D-lactate and intestinal villus height at 6 to 48 hours among CAR group,DF group and CAR ＋ DF group（ all P〈0. 05）. Conclusions The early gavage administration of carbachol,dietary fiber and carbachol combined with dietary fiber after DBI can reduce the intestinal mucosa damage and protect intestinal mucosal mechanical barrier,but the result of this study does not show the superiority of carbachol combined with dietary fiber to the one drug.