Intestinal barrier damage caused by trauma and lipopolysaccharide.
OBJECTIVE
To investigate the intestinal barrier function damage induced by trauma and infection in rats.


METHODS
Experimental models of surgical trauma and infection were established in rats. Adult Sprague-Dawley rats were divided into 4 groups: control group (n = 8), EN group (n = 10), PN group (n = 9) and Sep group (n = 8). The rats in PN and Sep groups were made into PN models that received isonitrogenous, isocaloric and isovolumic TPN solution during the 7-d period. Rats in EN and Sep groups received laparotomy and cervical catheterization on day 1 and received lipopolysaccharide injection intraperitoneally on d 7. On the 7(th) day all the animals were gavaged with lactulose and mannitol to test the intestinal permeability. Twenty-four hours later samples were collected and examined.


RESULTS
The inflammatory responses became gradually aggravated from EN group to Sep group. The mucosal structure of small intestine was markedly impaired in PN and Sep groups. There was a low response in IgA level in Sep group when compared with that of EN group. Lipopolysaccharide injection also increased the nitric oxide levels in the plasma of the rats. The intestinal permeability and bacterial translocation increased significantly in Sep group compared with that of control group.


CONCLUSIONS
One wk of parenteral nutrition causes an atrophy of the intestinal mucosa and results in a moderate inflammatory reaction in the rats. Endotoxemia aggravates the inflammatory responses that caused by laparotomy plus TPN, increases the production of nitric oxide in the body, and damages the intestinal barrier function.
Jinling Hospital, Nanjing University Medical School, 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province, China. dlahaolq@hotmail.com
Lian-An
LA
Ding
Jie-Shou
JS
Li
You-Sheng
YS
Li
Nian-Ting
NT
Zhu
Fang-Nan
FN
Liu
Li
L
Tan
D000818:Animals; D016470:Bacteremia / Q000473:pathology / Q000503:physiopathology; D018988:Bacterial Translocation / Q000502:physiology*; D007239:Infections / Q000473:pathology / Q000503:physiopathology*; D007413:Intestinal Mucosa / Q000473:pathology / Q000502:physiology* / Q000503:physiopathology; D007421:Intestine, Small / Q000473:pathology / Q000502:physiology / Q000503:physiopathology; D008070:Lipopolysaccharides / Q000633:toxicity; D008297:Male; D010289:Parenteral Nutrition, Total; D010539:Permeability; D051381:Rats; D017207:Rats, Sprague-Dawley; D014947:Wounds and Injuries / Q000473:pathology / Q000503:physiopathology*
D008070:Lipopolysaccharides