mRNA analysis. Whole bowel 7 days after SBR or sham surgery was analyzed by quantitative RT-PCR. A: glucagon (Gcg) mRNA [the precursor for glucagon-like peptide 2 (GLP2)] was more abundant in Ret+/− than WT mice after SBR and after sham surgery. B: epidermal growth factor (EGF) receptor (EGFR) mRNA was more abundant in Ret+/− than WT mice after sham surgery, but not after SBR. C: amphiregulin (Areg) mRNA was more abundant in Ret+/− than WT mice after SBR, but not after sham surgery. D: EGF mRNA levels were lower after SBR in WT mice than after sham surgery, but not statistically different in the SBR and sham groups of Ret+/− mice. E–H: mRNA levels for GLP2 receptor (GLP2R; E), epiregulin (Ereg; F), heparin-binding-EGF (HB-EGF; G), and transforming growth factor (TGF)-α (H) were equivalent in WT and Ret+/− after sham surgery or SBR (P > 0.05). Values are means ± SE. #P < 0.001. *P < 0.03.