Absorption and Metabolism of Pyridoxamine in Mice II. Transformation of Pyridoxamine to Pyridoxal in Intestinal Tissues

• Published in: Journal of Nutritional Science and Vitaminology Vol. 38; no. 3; pp. 227 - 233
• Main Authors: SAKURAI, Tae, ASAKURA, Tadashi, MIZUNO, Aritake, MATSUDA, Makoto
• Format: Journal Article
• Language: English
• Published: Japan Center for Academic Publications Japan 1992
• Subjects: Administration, Oral; Animals; Dose-Response Relationship, Drug; Hydrogen-Ion Concentration; Intestinal Absorption - physiology; Intestinal Mucosa - metabolism; intestine; Male; Mice; Pyridoxal - blood; pyridoxal kinase; pyridoxal phosphate; Pyridoxal Phosphate - blood; pyridoxamine; Pyridoxamine - administration & dosage; Pyridoxamine - pharmacokinetics; pyridoxine phosphate oxidase; Tritium
• ISSN: 0301-4800; 1881-7742
• DOI: 10.3177/jnsv.38.227

The absorption of pyridoxamine from the intestine of the mouse was studied in whole animals. [3H] Pyridoxamine was orally administered and the distribution of isotope between the six recognized forms of vitamin B6 was determined in portal blood after the administration. When small doses (1.4 or 14nmol) were administered, labeled pyridoxamine could hardly be found in the portal blood, although labeled pyridoxal and pyridoxal phosphate were found in the same blood. However, when a large amount (46 or 140nmol) was given, a significant amount of labeled pyridoxamine was found with labeled pyridoxal and pyridoxal phosphate in the portal blood. These results suggest that a physiological dose of pyridoxamine is rapidly transformed to pyridoxal in the intestial tissues and then released in the form of pyridoxal into the portal blood.