The role of epidermal growth factor in gastric epithelial proliferation in portal hypertensive rats exposed to stress.
OBJECTIVE
This study was designed to determine whether epidermal growth factor may have a role in the stomach of portal hypertensive rats after exposure to water immersion and restraint stress.


METHODS
Rats with portal hypertension (portal vein partial ligation) were studied to determine the proliferative response of the gastric epithelium to epidermal growth factor (EGF) during stress. The portal hypertensive rats received EGF (0, 10, 25, 50, and 100 microg/kg/day) subcutaneously for 7 days before water immersion restraint stress. Each rat was subjected to water immersion restraint stress for 6 hours, at the end of which the stomachs were excised to evaluate gross and microscopic mucosal damage, and gastric epithelial proliferation using proliferating cell nuclear antigen (PCNA) immunoreactivity.


RESULTS
The gross and microscopic mucosal damage were significantly greater in control or low dose EGF-pretreated (10 or 25 microg/kg/day) rats than in high dose EGF-pretreated (50 or 100 microg/kg/day) rats (p<0.01). These changes were accompanied by parallel alterations in the PCNA labeling index. The PCNA labeling index between high dose EGF-pretreated and control or low dose EGF-pretreated rats differed significantly (p<0.01).


CONCLUSIONS
This study clearly indicates that the influence of EGF on the proliferative response of the portal hypertensive (PHT) gastric epithelium to stress in rats was dose-dependent, suggesting an important role for EGF in the protection of PHT gastric mucosa from stress injury.
Hsieh
J S
JS
Department of Surgery, Kaohsiung Medical College, Taiwan.
Wang
J Y
JY
Huang
T J
TJ
D000818:Animals; D002455:Cell Division / Q000502:physiology*; D004815:Epidermal Growth Factor / Q000502:physiology*; D004847:Epithelial Cells / Q000473:pathology / Q000502:physiology*; D005753:Gastric Mucosa / Q000473:pathology / Q000503:physiopathology*; D006975:Hypertension, Portal / Q000473:pathology / Q000503:physiopathology*; D007124:Immunoenzyme Techniques; D008297:Male; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000150:complications*
D018809:Proliferating Cell Nuclear Antigen; D004815:Epidermal Growth Factor