Pharmacokinetics of germanium after po beta-carboxyethylgermanium sesquioxide in 24 Chinese volunteers
Abstract
AIM: To compare the pharmacokinetics after po different doses of beta-carboxyethylgermanium sesquioxide (Ge-132).
METHODS: An atomic absorption spectrophotometric system was used to measure germanium concentrations in plasma and urine samples after po Ge-132 1 (low dose, LD), 2.5 (medium dose, MD), and 4 (high dose, HD) g.m-2 in 24 healthy volunteers (one dose per 8 subjects).
RESULTS: T1/2 alpha (LD, 1.2 +/- 0.7 h; MD, 1.1 +/- 0.6 h; HD, 1.2 +/- 0.5 h), T1/2 beta (LD, 5.2 +/- 1.2 h; MD, 5.8 +/- 2.5 h; HD, 5.5 +/- 1.4 h) and Cl/F (LD, 33 +/- 12 L.h-1; MD, 35 +/- 10 L.h-1; HD, 33 +/- 11 L.h-1) were not dose-related. Tmax was between 0.75 h and 2 h. Cmax (LD, 5.3 +/- 2.2 mg.L-1; MD, 13 +/- 5 mg.L-1; HD 18 +/- 8 mg.L-1, HD) and AUC (LD, 31 +/- 13 mg.h.L-1; MD, 60 +/- 16 mg.h.L-1; HD, 79 +/- 42 mg.h.L-1) were positive correlation to the dose of Ge-132. Urine-eliminated germanium within 24 h accounted for 11 +/- 3% of LD, 9 +/- 3% of MD, and 6 +/- 5% of HD (calculated from Ge/F) and showed a negative correlation to the dose.
CONCLUSION: 1) Intracorporal process of Ge after po Ge-132 coincided with the first-order absorption and elimination with two-compartment kinetic model; 2) The amount of germanium eliminated in urine was below 11%.
Keywords:
METHODS: An atomic absorption spectrophotometric system was used to measure germanium concentrations in plasma and urine samples after po Ge-132 1 (low dose, LD), 2.5 (medium dose, MD), and 4 (high dose, HD) g.m-2 in 24 healthy volunteers (one dose per 8 subjects).
RESULTS: T1/2 alpha (LD, 1.2 +/- 0.7 h; MD, 1.1 +/- 0.6 h; HD, 1.2 +/- 0.5 h), T1/2 beta (LD, 5.2 +/- 1.2 h; MD, 5.8 +/- 2.5 h; HD, 5.5 +/- 1.4 h) and Cl/F (LD, 33 +/- 12 L.h-1; MD, 35 +/- 10 L.h-1; HD, 33 +/- 11 L.h-1) were not dose-related. Tmax was between 0.75 h and 2 h. Cmax (LD, 5.3 +/- 2.2 mg.L-1; MD, 13 +/- 5 mg.L-1; HD 18 +/- 8 mg.L-1, HD) and AUC (LD, 31 +/- 13 mg.h.L-1; MD, 60 +/- 16 mg.h.L-1; HD, 79 +/- 42 mg.h.L-1) were positive correlation to the dose of Ge-132. Urine-eliminated germanium within 24 h accounted for 11 +/- 3% of LD, 9 +/- 3% of MD, and 6 +/- 5% of HD (calculated from Ge/F) and showed a negative correlation to the dose.
CONCLUSION: 1) Intracorporal process of Ge after po Ge-132 coincided with the first-order absorption and elimination with two-compartment kinetic model; 2) The amount of germanium eliminated in urine was below 11%.