Biomaterial Database

Distribution of intrinsic factor-vitamin B12 receptors in human intestine. 1977

C H Hagedorn, and D H Alpers

A new rapid and accurate method for detecting vitamin B12-intrinsic factor (IF-B12) receptors was used to study the distribution of mucosal IF-B12 receptors in three human small intestines. IF-B12 receptors in human intestine are present in significant amounts in the entire distal three-fifths of intestine. Triokinase activity is absent in the distal two-fifths of intestine, and tryptophan oxygenase is present only in the distal one-sixth, or most terminal part of the ileum. These data suggest (1) biochemical functions in the ileum have different anatomical distributions, (2) IF-B12 receptors correspond most closely with the accepted anatomical definitions of the ileum, and (3) vitamin B12 malabsorption seen in resection or disease of terminal ileum may not be attributable solely to a deficiency of ileal receptors.

UI	MeSH Term	Description	Entries
D007082	Ileum	The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.
D007421	Intestine, Small	The portion of the GASTROINTESTINAL TRACT between the PYLORUS of the STOMACH and the ILEOCECAL VALVE of the LARGE INTESTINE. It is divisible into three portions: the DUODENUM, the JEJUNUM, and the ILEUM.	Small Intestine,Intestines, Small,Small Intestines
D007437	Intrinsic Factor	A glycoprotein secreted by the cells of the GASTRIC GLANDS that is required for the absorption of VITAMIN B 12 (cyanocobalamin). Deficiency of intrinsic factor leads to VITAMIN B 12 DEFICIENCY and ANEMIA, PERNICIOUS.	Factor, Intrinsic
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D010770	Phosphotransferases	A rather large group of enzymes comprising not only those transferring phosphate but also diphosphate, nucleotidyl residues, and others. These have also been subdivided according to the acceptor group. (From Enzyme Nomenclature, 1992) EC 2.7.	Kinases,Phosphotransferase,Phosphotransferases, ATP,Transphosphorylase,Transphosphorylases,Kinase,ATP Phosphotransferases
D011955	Receptors, Drug	Proteins that bind specific drugs with high affinity and trigger intracellular changes influencing the behavior of cells. Drug receptors are generally thought to be receptors for some endogenous substance not otherwise specified.	Drug Receptors,Drug Receptor,Receptor, Drug
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D014366	Tryptophan Oxygenase	A dioxygenase with specificity for the oxidation of the indoleamine ring of TRYPTOPHAN. It is a LIVER-specific enzyme that is the first and rate limiting enzyme in the kynurenine pathway of TRYPTOPHAN catabolism.	Tryptophan Pyrrolase,TDO Dioxygenase,Tryptophan 2,3-Dioxygenase,2,3-Dioxygenase, Tryptophan,Dioxygenase, TDO,Oxygenase, Tryptophan,Pyrrolase, Tryptophan,Tryptophan 2,3 Dioxygenase
D014805	Vitamin B 12	A cobalt-containing coordination compound produced by intestinal micro-organisms and found also in soil and water. Higher plants do not concentrate vitamin B 12 from the soil and so are a poor source of the substance as compared with animal tissues. INTRINSIC FACTOR is important for the assimilation of vitamin B 12.	Cobalamin,Cyanocobalamin,Cobalamins,Eritron,Vitamin B12,B 12, Vitamin,B12, Vitamin