title: The effect of massive small bowel resection and oral epidermal growth factor therapy on SGLT-1 distribution in rabbit distal remnant.
abstract: Small bowel resection decreases brush border membrane (BBM) glucose uptake kinetics. Oral epidermal growth factor (EGF) returns net glucose transport across intact tissue to control levels despite persistence of a defect in BBM glucose uptake. The purpose of this study was to examine the effects of resection and EGF treatment on sodium-dependent glucose cotransporter 1 (SGLT-1) expression in distal remnant tissue. New Zealand White rabbits (1 kg) underwent 70% small bowel resection (R). One group of resected animals (R-EGF) received oral EGF (40 microg/kg, days 3-8). Distal remnant tissue was harvested 10 d after surgery, and compared with controls (C). Mucosal SGLT-1 mRNA was measured by Northern blot, BBM SGLT-1 content by Western blot, and villus distribution of SGLT-1 protein and mRNA by immunofluorescence and in situ hybridization. Western blot indicated BBM from both resected and EGF-treated tissue had decreased SGLT-1 content (C, 0.55 +/- 0.04; R, 0.35 +/- 0.04; R-EGF, 0.35 +/- 0.03 trace OD; n = 5; p < 0.05). Northern blot revealed no alterations in mucosal SGLT-1 mRNA content in any group. SGLT-1 protein and mRNA localization in control tissues was characterized by a gradual increase in stain intensity from the base of the villus to the villus tip. Resection altered SGLT-1 protein and mRNA expression along the villus axis with intensity being strongest in the mid-villus region and little expression at the tip of the villus. Oral EGF normalized SGLT-1 protein and mRNA expression to control patterns. Resection alters SGLT-1 protein and mRNA expression along the villus axis, despite no change in total mucosal SGLT-1 mRNA content. EGF normalized villus SGLT-1 protein and mRNA distribution, without altering overall BBM SGLT-1 content or mucosal mRNA levels.
authors.affiliation: Department of Pediatrics, Faculty of Medicine, University of Calgary, 3330 University Calgary, Alberta T2N 4N1, Canada. dggall@ucalgary.ca
authors.forename: Brian M
authors.initials: BM
authors.lastname: Chung
authors.forename: Laurie E
authors.initials: LE
authors.lastname: Wallace
authors.forename: Robert K
authors.initials: RK
authors.lastname: Winkfein
authors.forename: Edward V
authors.initials: EV
authors.lastname: O'Loughlin
authors.forename: James A
authors.initials: JA
authors.lastname: Hardin
authors.forename: D Grant
authors.initials: DG
authors.lastname: Gall
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001485:Basement Membrane / Q000502:physiology; D015152:Blotting, Northern; D015153:Blotting, Western; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D015870:Gene Expression; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007421:Intestine, Small / Q000502:physiology* / Q000601:surgery*; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D009004:Monosaccharide Transport Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D011817:Rabbits; D051269:Sodium-Glucose Transporter 1
chemical_list: D008562:Membrane Glycoproteins; D009004:Monosaccharide Transport Proteins; D012333:RNA, Messenger; D051269:Sodium-Glucose Transporter 1; D004815:Epidermal Growth Factor