The expression and activation of EGF and c-NEU receptors are increased in enterocytes during intestinal adaptation.
OBJECTIVE
After massive small bowel resection (SBR), epidermal growth factor (EGF) and its intestinal receptor (EGF-R) play major roles during adaptation. The expression of a homologous enterocyte receptor termed c-neu (c-neu-R) is capable of forming heterodimers with EGF-R to facilitate cellular signaling. The purpose of this study was to determine the expression and activation of EGF-R and c-neu-R during the adaptive intestinal response to SBR.


METHODS
Male ICR mice underwent either SBR or sham surgery. After 1, 3, and 7 days, enterocytes were isolated and protein immunoprecipitated with antibody to either EGF-R or c-neu-R. Receptor protein expression and activation status were determined.


RESULTS
When compared with sham operation, the expression and activation status of both EGF-R (six- and twofold, respectively) and c-neu-R (nine- and twofold, respectively) were increased substantially in enterocytes from the adapting ileum after SBR by postoperative day 3. Minimal changes were appreciated for either EGF-R or c-neu-R expression or activation in the remnant bowel after enterocyte removal, liver, or kidney.


CONCLUSIONS
Both the expression and activation status of EGF-R and c-neu-R are increased substantially in enterocytes from the adapting ileum by postoperative day 3 after massive SBR. These changes provide a unique mechanism for the enterocyte to enhance cellular signaling in response to EGF during intestinal adaptation.
Falcone
R A
RA
Children's Hospital Medical Center, Department of Surgery, University of Cincinnati College of Medicine, OH 45229-3039, USA.
Shin
C E
CE
Erwin
C R
CR
Warner
B W
BW
D000222:Adaptation, Physiological; D000818:Animals; D066246:ErbB Receptors / Q000378:metabolism*; D007082:Ileum / Q000166:cytology* / Q000378:metabolism / Q000601:surgery*; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D011184:Postoperative Period; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*
D066246:ErbB Receptors; D018719:Erb-b2 Receptor Tyrosine Kinases