title: Clearance rates of biotinylated ferritins in canine: a possible physiological role of canine serum ferritin as an iron transporter.
abstract: To elucidate the physiological role of canine serum ferritin, we measured clearance rates of biotinylated ferritins in beagle. Biotinylated canine tissue ferritins were cleared rapidly from circulation. The clearance time (T 1/2) of liver ferritin (H/L subunit ratio = 0.43) was 6.8 to 11.8 min, and that of heart ferritin (H/L = 3.69) was 9.3 to 25.0 min. T 1/2 of biotinylated canine liver ferritin was independentof iron content, whereas canine heart apoferritin (T 1/2 = 31.2 and 32.7 min) was more slowly removed from circulation than the holoferritin. On the other hand, biotinylated recombinant bovine H-chain ferritin homopolymer show a much slower rate of removal (T 1/2 = 153.8 and 155.0 min) compared with the L-chain ferritin homopolymer (T 1/2 = 26.4 and 31.3 min). The rapid clearance of canine tissue ferritin suggests that serum ferritin is an iron transporter in canines.
authors.affiliation: Laboratories of Biochemistry, School of Veterinary Medicine and Animal Sciences, Kitasato University, Aomori 034-8628, Japan. orino@vmas.kitasato-u.ac.jp
authors.forename: Koichi
authors.initials: K
authors.lastname: Orino
authors.forename: Ayumi
authors.initials: A
authors.lastname: Terada
authors.forename: Akiko
authors.initials: A
authors.lastname: Yoshida
authors.forename: Shozo
authors.initials: S
authors.lastname: Okano
authors.forename: Seiichi
authors.initials: S
authors.lastname: Higuchi
authors.forename: Masahiro
authors.initials: M
authors.lastname: Natsuhori
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Watanabe
mesh_terms: D000818:Animals; D001692:Biological Transport; D019921:Biotinylation; D001835:Body Weight; D004285:Dogs; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005293:Ferritins / Q000097:blood* / Q000378:metabolism / Q000493:pharmacokinetics*; D007501:Iron / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D008297:Male; D008657:Metabolic Clearance Rate
chemical_list: D005293:Ferritins; D007501:Iron