Abstract:
BACKGROUND:Intravenous and subcutaneous microdialysis was performed to compare the free concentrations and pharmacokinetics of L-3, 4-dihyroxyphenylalanine (L-dopa) in blood and tissue in healthy subjects and in patients with Parkinson disease. METHODS:Nine healthy volunteers and 10 patients with Parkinson disease, stage 1. 5-2 according to the Hoehn-Yahr rating scale, took part of the study. In the patient group subcutaneous microdialysis and ordinary blood sampling were performed, whereas in the control group intravenous microdialysis was also performed. Microdialysis samples were collected in fractions of 15 min. The first two fractions were collected for analysis of basal concentrations. A blood sample was also taken. The patients were then given one tablet of Madopar((R)) (100 mg of L-dopa and 25 mg of benserazide), and the microdialysis was continued for another 210 min. Blood samples were obtained at 30-min intervals. RESULTS:The serum samples gave a significantly higher mean area under the curve (AUC; 491 +/- 139 micromol. min/L) than that for intravenous dialysates (235 +/- 55.3 micromol. min/L), suggesting a protein binding of 50%. The L-dopa concentrations from the subcutaneous dialysates matched those from the intravenous dialysates, indicating rapid distribution of L-dopa to the tissues. CONCLUSIONS:Parkinsonian patients in early stages of the disease have a pharmacokinetic pattern of free L-dopa similar to that of healthy subjects. Comparison of AUCs from microdialysis with ordinary serum analysis revealed data indicating significant protein binding. Microdialysis is a suitable and easily applied tool in pharmacokinetic studies.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Dizdar N,Kullman A,Norlander B,Olsson JE,Kagedal Bsubject
Has Abstractpub_date
1999-10-01 00:00:00pages
1813-20issue
10eissn
0009-9147issn
1530-8561journal_volume
45pub_type
临床试验,杂志文章abstract::We describe the sensitive and precise determination 5-hydroxytryptophan in plasma from patients treated with this compound. The method is based on solvent extraction of plasma, high-performance liquid chromatography and continuous fluorometric detection after reaction with phthaldialdehyde in strong acid. The combined...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1978-02-01 00:00:00
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journal_title:Clinical chemistry
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更新日期:1987-10-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/49.7.1133
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-03-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
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journal_title:Clinical chemistry
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doi:
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-08-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1996-08-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-05-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1993-01-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1981-07-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1979-08-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1986-02-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1997-09-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1997-05-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1998-12-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1990-02-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1976-03-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
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journal_title:Clinical chemistry
pub_type: 杂志文章
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journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1994-11-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章,meta分析
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1984-07-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
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