Clearance rates of biotinylated ferritins in canine: a possible physiological role of canine serum ferritin as an iron transporter.
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.
Orino
Koichi
K
Laboratories of Biochemistry, School of Veterinary Medicine and Animal Sciences, Kitasato University, Aomori 034-8628, Japan. orino@vmas.kitasato-u.ac.jp
Terada
Ayumi
A
Yoshida
Akiko
A
Okano
Shozo
S
Higuchi
Seiichi
S
Natsuhori
Masahiro
M
Watanabe
Kiyotaka
K
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
D005293:Ferritins; D007501:Iron