Document Detail

Rapid and steady-state amino acid transport in perfused human fibroblasts and colon adenocarcinoma cells: effects of methotrexate.
MedLine Citation:
PMID:  2112948     Owner:  NLM     Status:  MEDLINE    
Initial and steady-state uptakes of serine and phenylalanine by human fibroblasts and human colon tumour cells were studied applying a double isotope dilution technique to perfused populations of cultivated cells retained on microcarrier beads. This new method permits the differentiation of the unidirectional transport parameters and can also distinguish between membrane-associated processes and independently intracellular events in isolated cells. High initial L-serine uptake values in colon adenocarcinoma cells became negative under steady-state conditions. To determine if the observed negative L-serine uptake was produced by the rapid efflux of intracellular L-[3H]serine, the cells were treated with methotrexate (MTX) (an inhibitor of cytosolic dihydrofolate reductase). The modified curve of L-[3H]serine uptake after MTX treatment suggests that, under these experimental conditions, net serine transport is non concentrative in colon tumour cells and could be modulated by the rate of intracellular serine metabolism; it also suggests that MTX does not directly affect serine transport in perfused human colon adenocarcinoma cells. Initial and steady-state uptakes of phenylalanine were high in both fibroblasts and tumour cells and were unaffected by MTX treatment.
S Perán; M Muñoz; M T Saiz
Related Documents :
9045638 - A protein-tyrosine kinase-regulated, ph-dependent, carrier-mediated uptake system for f...
2615558 - Increase of poly(l-lysine) uptake but not fluid phase endocytosis in neuraminidase pret...
3208618 - Flow cytofluorometric analysis of the uptake of the fluorescent fatty acid pyrene-dodec...
19962438 - Transport of phenylethylamine at intestinal epithelial (caco-2) cells: mechanism and su...
8534368 - Molecular cloning and cell cycle-dependent expression of a novel gene that is homologou...
851268 - Increased sensitivity of canine sarcoma cells to lysis with alloantiserum and complemen...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Biochimica et biophysica acta     Volume:  1024     ISSN:  0006-3002     ISO Abbreviation:  Biochim. Biophys. Acta     Publication Date:  1990 May 
Date Detail:
Created Date:  1990-07-26     Completed Date:  1990-07-26     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0217513     Medline TA:  Biochim Biophys Acta     Country:  NETHERLANDS    
Other Details:
Languages:  eng     Pagination:  233-40     Citation Subset:  IM    
Department of Biochemistry and Molecular Biology, University of Málaga, Spain.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Adenocarcinoma / drug therapy,  metabolism*
Amino Acids / metabolism*
Biological Transport
Colonic Neoplasms / drug therapy,  metabolism*
Fibroblasts / drug effects,  metabolism*
Methotrexate / pharmacology*
Phenylalanine / metabolism
Serine / metabolism
Tumor Cells, Cultured
Reg. No./Substance:
0/Amino Acids; 56-45-1/Serine; 59-05-2/Methotrexate; 63-91-2/Phenylalanine

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Kinetics and mechanism of transfer of reduced and carboxymethylated apolipoprotein A-II between phos...
Next Document:  Identification and reconstitution of the nucleoside transporter of CEM human leukemia cells.