title: Insulin-like growth factor-I stimulates Na+-dependent glutamine absorption in piglet enterocytes.
abstract: Agents that enhance intestinal glutamine transport may be useful under conditions in which intestinal mucosal function is compromised. Here we examined whether oral administration of insulin-like growth factor (IGF-I) stimulates absorption of L-glutamine in piglet intestine. Colostrum-deprived piglets received human recombinant IGF-I (3.5 mg/kg/day) or vehicle orogastrically every 8 hr for four days after birth. Piglets were killed on day 5 and the proximal jejunum was removed. Basal electrical parameters and L-glutamine-stimulated changes in short-circuit current were measured in muscle-stripped tissues, and rates of L-glutamine uptake were measured in everted jejunal sleeves. Oral IGF-I had no effect on jejunal mucosal mass. Short-circuit current responses to mucosal addition of 10 mM L-glutamine were increased by oral IGF-I. Total and carrier-mediated uptakes of L-glutamine per milligram were greater in tissues from IGF-I-treated piglets due to a significantly greater maximal rate of uptake (Jmax). Thus, oral administration of IGF-I stimulates Na+-dependent glutamine absorption in piglet small intestine, an effect that is independent of changes in intestinal mucosal mass.
authors.affiliation: Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison 53706, USA.
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Alexander
authors.forename: Hannah V
authors.initials: HV
authors.lastname: Carey
mesh_terms: D000284:Administration, Oral; D026923:Amino Acid Transport Systems, Basic / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D020895:Enterocytes / Q000187:drug effects / Q000378:metabolism*; D005973:Glutamine / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000378:metabolism; D007583:Jejunum / Q000378:metabolism; D013002:Somatomedins / Q000008:administration & dosage / Q000494:pharmacology*; D013552:Swine
chemical_list: D026923:Amino Acid Transport Systems, Basic; D013002:Somatomedins; C077738:sodium-dependent glutamine transporter; D005973:Glutamine