title: Development of the neonatal rat small intestinal barrier to nonspecific macromolecular absorption. II. Role of dietary corticosterone.
abstract: The role of oral corticosterone (C) in the maturation of the neonatal rat jejunal barrier to the absorption of nonspecific macromolecules was evaluated. This was done by adding C to the diet of rat pups weaned at an early age, 17 d, from maternal milk (MM) to either a protein hydrolysate (PH) or soy (S) artificial formula. Both PH and S are known to cause a delay in small intestinal closure to the absorption of a 40-kD glycoprotein tracer, horseradish peroxidase (HRP), on d 21 of age. C was added to PH and S formulas from d 17 to 21 at 0.26 mumol/L (10 micrograms/dL), a level found in the MM of lactating rat dams, or at 10.29 mumol/L (400 micrograms/dL) (PH + 10C, PH + 400C) (S + 10C, S + 400C). Controls consisted of rat pups fed PH or S without C and animals remaining with the dam on MM. The delay in jejunal closure to HRP on d 21 in both PH- and S-fed pups was prevented by C supplementation at both the higher and lower concentrations. Geometric mean (95% confidence intervals) jejunal HRP absorption in PH + 10C pups was 74 (32,167) IU HRP/mL x cm x min, less than in pups fed PH without C [353 (200,615); p less than 0.05] and indistinguishable from HRP absorption in MM-fed animals [111 (79,154)]. HRP absorption in PH + 400C pups [52 (23,115)] was also less than that in animals fed PH without C (p less than 0.01) and indistinguishable from those fed MM.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, New York 11030.
authors.forename: S
authors.initials: S
authors.lastname: Teichberg
authors.forename: R A
authors.initials: RA
authors.lastname: Wapnir
authors.forename: J
authors.initials: J
authors.lastname: Moyse
authors.forename: F
authors.initials: F
authors.lastname: Lifshitz
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D003345:Corticosterone / Q000008:administration & dosage / Q000494:pharmacology*; D004032:Diet; D006735:Horseradish Peroxidase / Q000493:pharmacokinetics; D007408:Intestinal Absorption / Q000187:drug effects*; D007583:Jejunum / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology; D008892:Milk; D051381:Rats; D011919:Rats, Inbred Strains; D015430:Weight Gain / Q000187:drug effects
chemical_list: D006735:Horseradish Peroxidase; D003345:Corticosterone