       Document 0007
 DOCN  M9460007
 TI    Enzymatic assay for measurement of zidovudine triphosphate in peripheral
       blood mononuclear cells.
 DT    9404
 AU    Robbins BL; Rodman J; McDonald C; Srinivas RV; Flynn PM; Fridland A;
       Department of Infectious Diseases, St. Jude Children's Research;
       Hospital, Memphis, Tennessee 38101.
 SO    Antimicrob Agents Chemother. 1994 Jan;38(1):115-21. Unique Identifier :
       AIDSLINE MED/94190034
 AB    In this report, we describe a new method to measure intracellular
       zidovudine triphosphate (ZDV-TP) levels in peripheral blood mononuclear
       cells (PBMCs) from patients treated with ZDV by utilizing inhibition of
       human immunodeficiency virus type 1 reverse transcriptase activity by
       ZDV-TP. Intracellular levels of ZDV-TP were determined with our
       enzymatic assay in PBMCs isolated from the blood of healthy individuals
       incubated with different concentrations of labeled ZDV and were
       validated by high-performance liquid chromatography separation and
       liquid scintillation counting of the radioactive ZDV-TP. These methods
       gave virtually identical results over a range of ZDV-TP concentrations
       from 150 to 900 fmol. ZDV-TP recoveries were over 90%, and the limit of
       quantitation of ZDV-TP by this method was 20 to 50 fmol. To demonstrate
       the utility of the method, plasma ZDV and intracellular ZDV-TP
       concentrations were measured at serial time points over 6 h in 12 human
       immunodeficiency virus-infected volunteers following a single 100- or
       500-mg oral dose of ZDV. Systemic oral clearance rates were similar to
       those in previous studies with adults but were highly variable (range,
       0.86 to 2.75 liters/h/kg of body weight). The area under the plasma
       concentration versus time curve increased significantly (P < 0.0005)
       with the dose from a median value of 1.2 mg.h/liter at the lower dose to
       4.2 mg.h/liter at the higher dose.(ABSTRACT TRUNCATED AT 250 WORDS)
 DE    Antiviral Agents/*BLOOD/IMMUNOLOGY/PHARMACOKINETICS  Cells, Cultured
       Chromatography, High Pressure Liquid  Half-Life  Human  HIV
       Seropositivity/BLOOD  HIV-1/ENZYMOLOGY  Monocytes/*CHEMISTRY
       Radioimmunoassay  Reverse Transcriptase/ANTAGONISTS & INHIB  Support,
       Non-U.S. Gov't  Support, U.S. Gov't, P.H.S.  T-Lymphocytes/CHEMISTRY
       Zidovudine/*ANALOGS & DERIVATIVES/BLOOD/IMMUNOLOGY/  PHARMACOKINETICS
       JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

