[A compartment model of Tc-99m-DTPA-galactosyl-human serum albumin for evaluating liver function].
Technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin (99mTc-GSA) is a new liver scintigraphy agent which binds to asialoglycoprotein receptor in hepatocyte. Studies were performed in three normal volunteers and 11 patients with liver cirrhosis. Time-activity curves for the heart and liver were obtained for 60 min following an i.v. injection of 99mTc-GSA (1 mg/185 MBq). We introduced five compartments to describe 99mTc-GSA: 1) extrahepatic blood, 2) hepatic blood, 3) receptor, 4) interstitial fluid and 5) urine. The %ID of 99mTc-GSA in blood and the hepatic blood volume were obtained from the extrapolation of the biexponential fitting for the heart and liver curves. Michaelis-Menten type saturation kinetics was applied to the process of receptor-ligand binding. Numerical analysis solved the simultaneous differential equations that were introduced from the compartment model. Hepatic blood flow was 1,651 +/- 131 ml/min, maximal removal rate for the ligand was 0.547 +/- 0.069 mg/min in normal controls. Both results were significantly decreased in patients with liver cirrhosis compared with normal controls. Present study may provide a novel method for the diagnosis of liver function that allows independent quantification of the hepatic blood flow and the receptor population.
Ha-Kawa
S K
SK
Department of Radiology, Kansai Medical University.
Kojima
M
M
Tanaka
Y
Y
D000328:Adult; D001825:Body Fluid Compartments; D005260:Female; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging*; D008102:Liver Circulation; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging; D008111:Liver Function Tests; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D011877:Radionuclide Imaging; D013668:Technetium Tc 99m Aggregated Albumin / Q000493:pharmacokinetics; D016284:Technetium Tc 99m Pentetate / Q000493:pharmacokinetics
D013668:Technetium Tc 99m Aggregated Albumin; C070561:technetium Tc 99m DTPA-galactosyl-human serum albumin; D016284:Technetium Tc 99m Pentetate