Increased duodenal expression of transforming growth factor-alpha and epidermal growth factor during experimental colitis in rats.
OBJECTIVE
Epidermal growth factor (EGF) and transforming growth factor alpha (TGFalpha) protect gastrointestinal mucosa against injury. Having shown earlier, that TGFalpha but not EGF is locally increasingly expressed after mucosal injury in the colon, we now wanted to explore the pattern of expression of EGF and TGFalpha in the remaining gastrointestinal tract and to infer from the pattern of expression, to possible signals for the induction of the growth factor expression and further mechanisms for mucosal protection.


METHODS
The trinitrobenzene sulfonic acid/ethanol-induced model of colitis in rats was used. TGFalpha-mRNA and EGF-mRNA expression was evaluated in inflamed and noninflamed colon, in the ileum, jejunum, duodenum, stomach, and in the submandibulary glands.


RESULTS
A significant increase of TGFalpha-mRNA and EGF-mRNA expressions was detected in the duodenal mucosa and a significant increase in TGFalpha-mRNA expression was observed in the inflamed colonic mucosa after mucosal injury in the colon within the first hours of colitis.


CONCLUSIONS
The increased expression of EGF and TGFalpha in the duodenum may lead to neutralization of gastric acid and proteolytic enzymes in the upper gastrointestinal tract during the course of colitis. Possible signals for the increased expression of EGF and TGFalpha presumably are fasting, parasympathetic, or adrenergic parts of the enteric nervous system or yet unknown mechanisms.
Bulut
Kerem
K
aDepartment of Internal Medicine I, St Josef Hospital, Ruhr-University of Bochum, Kliniken Essen-Mitte, Essen, Germany.
Felderbauer
Peter
P
Hoeck
Karoline
K
Schmidt
Wolfgang E
WE
Hoffmann
Peter
P
D000818:Animals; D003092:Colitis / Q000276:immunology / Q000378:metabolism*; D003106:Colon / Q000378:metabolism; D004386:Duodenum / Q000378:metabolism*; D004815:Epidermal Growth Factor / Q000235:genetics*; D000431:Ethanol; D015870:Gene Expression; D007413:Intestinal Mucosa / Q000276:immunology / Q000378:metabolism*; D008297:Male; D023421:Models, Animal; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D016211:Transforming Growth Factor alpha / Q000235:genetics*; D014302:Trinitrobenzenesulfonic Acid
D012333:RNA, Messenger; D016211:Transforming Growth Factor alpha; D000431:Ethanol; D004815:Epidermal Growth Factor; D014302:Trinitrobenzenesulfonic Acid