Sphingosine 1-phosphate and sphingosine kinase activity during chicken embryonic development.

The chicken embryo has been well used in studies of the developmental process, and during development sphingosine and sphingosine 1-phosphate (So1P) are considered critical mediators of cell death and survival. In this study, we compared the sphingolipid contents of chicken embryos during the early embryonic development period from day 3 to day 6. HPLC analyses of sphingosine and So1P in chicken embryos revealed that sphingosine levels were greatly reduced on day 4 whereas So1P levels were not significantly changed. Sphingosine kinase (Sphk) activities, which require sphingosine as substrate to produce So1P, were also greatly reduced on day 4. Collectively, we found sphingosine levels and Sphk activities, but not So1P levels are changed in early stage of chicken embryos development.

High performance liquid chromatographic analysis an pharmacokinetic characteristics of ID-7181, a novel quaternary ammoniopropenyl cephalosporin, following intravenous and intramuscular injections to rats.

The purpose of the present study was to examine the pharmacokinetic characteristics of 7-[(z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-methoxyiminoacetamido]-3-[(E)-3-(E)-(1-carbamoyl-1-propene-3-yl) 3-ethylmethylammonio]-1-propene- 1-yl]-3-cepheme-4-carboxylate (CAS 206126-08-1, ID-7181), a novel quaternary ammoniopropenyl cephalosporin that contains two vinyl groups at the C-3 side chain, after being administered intravenously (i.v.) or intramuscularly (i.m.) to rats. An HPLC-based method was developed to analyze the ID-7181 levels in the plasma, bile, urine, feces, and tissue homogenates and validated in a pharmacokinetic study. The plasma concentration of ID-7181 decreased to below the quantifiable limit at 6 h after the i.v. administration to rats following doses of 2-10 mg/kg, yielding a t(1/2,beta) of 77.7-81.7 t(1/2) after i.m. doses of 10-50 mg/kg were 79.3-127 min. The total plasma clearance (CLt) decreased with the nonlinear pharmacokinetics with an increase in the i.m. dose from 10 to 50 mg/kg in rats, while it was not significantly altered after the i.v. dose. The bioavailability of the i.m. administered ID-7181 was 43-63 %. Of the various tissues tested, ID-7181 was mainly distributed in the kidney after the i.v. or i.m. administration. The ID-7181 concentrations in the kidney 0.5 h after being administered i.v. or i.m. were comparable to the plasma concentrations shortly after being administered i.v. or the Cmax after being administered i.m. However, the ID-7181 concentrations in the tissues 6 h after being administered i.v. or i.m. decreased to low i.m. were 35-45 % of the initial doses. The corresponding values in the bile 6 h after being administered i.v. or i.m. were 0.5-1% of the initial dose. In conclusion, ID-7181, administered i.v. or i.m., is mainly distributed to the kidney. By 6 h after i.v. or i.m. administration, the ID-7181 concentrations in the various tissues decreased to very low levels. Moreover, the majority of ID-7181 appeared to be excreted in the urine.

Pharmacokinetics of 11-hydroxyaclacinomycin X (ID-6105), a novel anthracycline, after i.v. bolus multiple administration in rats.

We investigated the pharmacokinetics of 11-hydroxyaclacinomycin X (ID-6105), a novel anthracycline, after intravenous (i.v.) bolus administration at a multiple dose every 24 h for 5 days in rats. To analyze ID-6105 levels in biological samples, we used an HPLC-based method which was validated in a pharmacokinetic study by suitable criteria. The concentrations of ID-6105 after the multiple administration for 5 days were not significantly different from the results after the single administration. The t1/2alpha, t1/2beta, Vdss, and CLt after the multiple administration were not significantly different from the values after the single administration. Moreover, the concentrations of ID-6105 1 min at day 1-5 after i.v. bolus multiple administration did not show the significant difference. Of the various tissues, ID-6105 mainly distributed to the kidney, lung, spleen, adrenal gland, and liver after i.v. bolus multiple administration. ID-6105 concentrations in the kidney or lung 2 h after i.v. bolus administration were comparable to the plasma concentration shortly after i.v. bolus administration. However, the ID-6105 concentrations in various tissues 48 h after i.v. bolus administration decreased to low levels. ID-6105 was excreted largely in the bile after i.v. bolus multiple administration at the dose of 3 mg/kg. The amounts of ID-6105 found in the bile by 12 h or in the urine by 48 h after the administration were calculated to be 14.1% or 4.55% of the initial dose, respectively, indicating that ID-6105 is mostly excreted in the bile. In conclusion, ID-6105 was rapidly cleared from the blood and transferred to tissues, suggesting that ID-6105 might not be accumulated in the blood following i.v. bolus multiple dosages of 3 mg/kg every 24 h for 5 days. By 48 h after i.v. bolus administration, ID-6105 concentrations in various tissues had decreased to very low levels. The majority of ID-6105 appears to be excreted in the bile.

HPLC analysis and pharmacokinetic characteristics of 11-hydroxyaclacinomycin X (ID-6105), a novel anthracycline, in rats and beagle dogs.

We investigated the pharmacokinetic characteristics of 11-hydroxyaclacinomycin X (ID-6105), a novel anthracycline, after intravenous (i.v.) bolus administration in rats and beagle dogs. We developed an HPLC-based method to analyze ID-6105 levels in plasma, bile, urine, feces, and tissue homogenates and validated the method in a pharmacokinetic study. The plasma concentration of ID-6105 decreased to below the quantifiable limit (0.02 microg/ml) at 4 and 8 h after i.v. administration in rats at doses of 2 and 10 mg/kg, respectively (t(1/2,alpha) and t(1/2,beta) of 0.78 and 17.8 min at a dose of 2 mg/kg, 0.91 and 176 min at a dose of 10 mg/kg, respectively). The AUC increased with nonlinear pharmacokinetics following the dosage increase from 2 to 10 mg/kg in rats, while the pharmacokinetics were not significantly altered in beagle dogs following a dosage increase from 0.5 to 2.5 mg/kg. Of the various tissues tested, ID-6105 was mainly distributed in the lung, spleen, kidney, adrenal gland, and liver after i.v. bolus administration. ID-6105 levels in the lung or kidney 2 h after i.v. bolus administration were comparable to the initial plasma concentration. However, the ID-6105 concentrations in various tissues 48 h after i.v. bolus administration became too small to measure. The cumulative amounts of ID-6105 found in the bile 48 h after the administration of 2 and 10 mg/kg were calculated to be 26.7 and 18.5% of the initial dose, respectively. The corresponding values in the urine 72 h after i.v. administration were 4.33 and 3.07% of the initial dose, suggesting that ID-6105 is mostly excreted in the bile. In conclusion, our observations indicate that ID-6105 was rapidly cleared from the blood and transferred to tissues such as the lung, spleen, kidney, and liver 2 h after i.v. bolus administration. Moreover, the majority of ID-6105 appears to be excreted in the bile by 24 h after i.v. bolus administration.