Evaluation of the reticuloendothelial system function by the vascular clearance of chondroitin sulfate iron colloid.
Vascular clearance of chondroitin sulfate iron colloid (CSFe) was evaluated as a test for the reticuloendothelial system (RES) in rabbits. Injected CS59Fe was taken up by the RES in the liver (49%) and bone marrow (41%) after 60 min, suggesting its application for the RES function test. The clearance rate (K-value) of CSFe from the blood was calculated by measuring serum Fe concentrations after releasing iron from CSFe at certain intervals after injection. Depending upon different injected doses, K-values were varied and the phagocytic velocity, computed by multiplying K-values by corresponding injected doses, reached a plateau at high doses, indicating the phagocytosis of CSFe by the RES takes a saturation process. Double-reciprocal plotting of the dose and the phagocytic velocity showed a linear relationship, which provided the data on the maximum phagocytic velocity (Vmax), 0.122 mg/kg/min, and the CSFe concentration producing 1/2 Vmax (Kp), 0.426 mg/kg. Thus, this CSFe clearance test can be used for the evaluation of the RES function.
Ishida
H
H
Department of Surgery II, Osaka University Medical School, Japan.
Kido
Y
Y
Tsujinaka
T
T
Hayashida
Y
Y
Ogawa
A
A
Iijima
S
S
Homma
T
T
Yokota
M
M
Sakaue
M
M
Kurahori
T
T
D000818:Animals; D002809:Chondroitin Sulfates / Q000097:blood / Q000493:pharmacokinetics*; D007501:Iron / Q000097:blood; D008297:Male; D008657:Metabolic Clearance Rate; D012157:Mononuclear Phagocyte System / Q000502:physiology*; D010587:Phagocytosis; D011817:Rabbits; D014018:Tissue Distribution
D002809:Chondroitin Sulfates; D007501:Iron