title: The absorption of free vitamin B12 and R protein-bound vitamin B12 in the diagnosis of pancreatic exocrine insufficiency in rats.
abstract: Vitamin B12 (B12) absorption was studied in rats following biliopancreatic duct ligation. The absorption of free B12, as well as of hog R protein-bound B12, was markedly impaired after both intragastric and intraduodenal administration in these rats. The intraduodenal administration of a mixture of pancreatic extract and sodium bicarbonate (NaHCO3) improved the absorption of both free and R protein-bound B12. However, pancreatic extract without NaHCO3 was ineffective in this respect. Intraduodenal administration of NaHCO3 without pancreatic extract worsened the R protein-bound B12 absorption. This finding would indicate that the degradation of R protein by proteolytic enzymes, in the intestine of rats with pancreatic juice exclusion, is inhibited by NaHCO3.
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Kyoto University, Japan.
authors.forename: W L
authors.initials: WL
authors.lastname: Chen
authors.forename: R
authors.initials: R
authors.lastname: Morishita
authors.forename: T
authors.initials: T
authors.lastname: Eguchi
authors.forename: T
authors.initials: T
authors.lastname: Kawai
authors.forename: H
authors.initials: H
authors.lastname: Uchino
mesh_terms: D000818:Animals; D001639:Bicarbonates / Q000494:pharmacology; D001652:Bile Ducts; D010188:Exocrine Pancreatic Insufficiency / Q000175:diagnosis*; D007408:Intestinal Absorption; D008026:Ligation; D010184:Pancreatic Extracts / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000494:pharmacology; D017693:Sodium Bicarbonate; D014155:Transcobalamins; D014805:Vitamin B 12
chemical_list: D001639:Bicarbonates; D010184:Pancreatic Extracts; D014155:Transcobalamins; D017693:Sodium Bicarbonate; D012964:Sodium; D014805:Vitamin B 12