The distribution of endogenous epidermal growth factor after small bowel resection suggests increased intestinal utilization during adaptation

Background/Purpose:Although exogenous epidermal growth factor (EGF) amplifi es adaptation after massive small bower resection (SBR), the role for endog enous EGF is unclear. The authors sought to determine whether SBR was assoc iated with changes in the levels of EGF in the serum;saliva, or urine and E GF receptor (EGF-R) signaling in the ileum. Methods: Male ICR mice underwent 50% proximal SBR or sham surgery bower tra nsection/reanastomosis). After 3 days, levels of EGF were measured by enzym e-linked immunosorbent assay (ELISA) in the serum; saliva, and urine. EGF-R activation was measured in isolated ileal enterocytes by probing an EGF-R immunoprecipitate with an antibody to phosphotyrosine. Results: When compared with sham, SBR resulted in no change in serum, incre ased salivary (2209 +/- 266 nmol SBR v 1183 +/- 119 nmol sham, P < .05) and decreased urinary (417 +/- 58 nmol SBR v 940 +/- 143 nmol sham; P < .05) E GF levels. EGF-R activation increased 2.5-fold after SBR. Conclusions: Increased salivary and reduced urinary EGF linked with enhance d EGF-R activation suggests increased ileal utilization of EGF during adapt ation, This observation, along with the known beneficial effects of exogeno us EGF, infers a crucial role for endogenous EGF in the pathogenesis of int estinal adaptation after SBR. J Pediatr Surg 34:22-26. Copyright (C) 1999 b y W.B. Saunders Company.