Biochemical properties of canine serum ferritin: iron content and nonbinding to concanavalin A.
A sandwich enzyme-linked immunosorbent assay using H-subunit-rich canine heart ferritin as a standard has been developed for measuring canine serum ferritin which is H-subunit-rich. Serum ferritin concentrations in 51 normal dogs ranged from 143 to 1766 ng ml(-1), with a mean value of 479 +/- 286 (SD) ng ml(-1). Serum ferritin iron concentrations as determined by an immunoprecipitation technique ranged from 30.4 to 115.9 ng ml(-1) in 15 normal dogs with serum ferritin protein levels of 298 to 959 ng ml(-1). There was a significant linear correlation between the serum ferritin iron and protein levels (r=0.9441, P<0.001), and the mean iron/protein ratio of serum ferritin was 0.112 +/- 0.017. When canine sera were incubated with concanavalin A-Sepharose 4B, we observed the apparent binding of serum ferritin to concanavalin A. However, ferritin obtained by heat-treating the sera at pH 4.8 to remove the ferritin-binding proteins did not bind to the lectin. These results suggest that canine serum ferritin contains a considerable amount of iron but no concanavalin A-binding G subunit present in human serum ferritin.
Laboratory of Biochemistry, School of Veterinary Medicine and Animal Sciences, Kitasato University, Towada, Aomori, Japan. watanabe@vmas.kitasato-u.ac.jp
K
K
Watanabe
N
N
Muranishi
Y
Y
Murata
K
K
Orino
S
S
Okano
S
S
Yamamoto
D000818:Animals; D003208:Concanavalin A / Q000378:metabolism; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000592:standards; D005293:Ferritins / Q000097:blood* / Q000737:chemistry* / Q000276:immunology; D007120:Immunochemistry; D066298:In Vitro Techniques; D007501:Iron / Q000032:analysis / Q000097:blood; D008099:Liver / Q000737:chemistry; D009206:Myocardium / Q000737:chemistry; D011485:Protein Binding; D021122:Protein Subunits; D012015:Reference Standards
D021122:Protein Subunits; D003208:Concanavalin A; D005293:Ferritins; D007501:Iron