Abstract | PURPOSE: RESULTS: The effects of inhibition of the ENT inhibitors, nitrobenzylthioinosine ( NBMPR) and nitrobenzylthioguanosine, on THP and DOX uptake by Ehrlich cells was negligible. THP uptake, but not DOX uptake, partially depended on an inwardly directed Na(+) gradient, and the uptake was inhibited by all the inhibitors of CNT examined. Furthermore, efflux of [(3)H] uridine from Ehrlich cells was stimulated by the addition of THP to the extracellular compartment, which was definitive evidence of CNT-mediated uptake of THP. The mRNA for CNT2, but not that for CNT3, was detected in Ehrlich cells, which is consistent with the characteristics of [(3)H] uridine uptake. In the cells, formycin B, a representative CNT2 ligand, had cis-inhibitory and trans-stimulatory effects on THP uptake. CONCLUSION: These results demonstrate that THP, but not DOX, is taken up into Ehrlich cells partially via a uridine-transportable CNT.
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Authors | Katsuhito Nagai, Kazuki Nagasawa, Atsushi Ishimoto, Sadaki Fujimoto |
Journal | Cancer chemotherapy and pharmacology
(Cancer Chemother Pharmacol)
Vol. 51
Issue 6
Pg. 512-8
(Jun 2003)
ISSN: 0344-5704 [Print] Germany |
PMID | 12679883
(Publication Type: Journal Article)
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Chemical References |
- Antibiotics, Antineoplastic
- Formycins
- Nucleoside Transport Proteins
- RNA, Messenger
- formycin B
- Doxorubicin
- Sodium
- pirarubicin
- Uridine
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Topics |
- Animals
- Antibiotics, Antineoplastic
(metabolism)
- Carcinoma, Ehrlich Tumor
(metabolism)
- Doxorubicin
(analogs & derivatives, metabolism)
- Formycins
(pharmacology)
- Mice
- Nucleoside Transport Proteins
(antagonists & inhibitors, metabolism)
- RNA, Messenger
(biosynthesis, genetics)
- Reverse Transcriptase Polymerase Chain Reaction
- Sodium
(physiology)
- Tumor Cells, Cultured
- Uridine
(metabolism)
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