Reduced store-operated Ca(2+) currents in rat basophilic leukaemia cells cultured under serum-free conditions.
Influx of Ca(2+) represents an important regulatory signal in the process of cell proliferation. However, little is known about how Ca(2+) entry changes during the cell-cycle. Patch-clamp experiments and microfluorimetry show that store-operated Ca(2+) entry was substantially reduced in rat basophilic leukaemia cells cultured for 24h under serum-free conditions. Likewise, retinoic acid treatment blocked Ca(2+) influx activated by store depletion via inositol 1,4,5-trisphosphate. Both procedures are known to arrest cells at the G0/G1 boundary of the cell-cycle and induced a reduction in 5-bromo 2'-deoxyuridine incorporation into DNA. Ca(2+) release from the stores remained unaltered and two types of K(+) currents were not affected in cells after serum starvation. The specific reduction in Ca(2+) entry was not detected when using aphidicolin, 5-fluorouracil or thymidine to synchronise the cell-cycle. These data suggest that store-operated Ca(2+) influx changed during cell-cycle progression which might have important implications for cell growth.
Bödding
M
M
University Laboratory of Physiology, Parks Road, Oxford, UK. matthias.boedding@med-rz.uni-sb.de
D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology; D016590:Aphidicolin / Q000494:pharmacology; D001973:Bromodeoxyuridine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D016895:Culture Media, Serum-Free / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005472:Fluorouracil / Q000494:pharmacology; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000378:metabolism; D015544:Inositol 1,4,5-Trisphosphate / Q000494:pharmacology; D007938:Leukemia / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D011188:Potassium / Q000494:pharmacology; D015221:Potassium Channels / Q000378:metabolism; D051381:Rats; D013997:Time Factors; D014212:Tretinoin / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D000964:Antimetabolites, Antineoplastic; D000970:Antineoplastic Agents; D016895:Culture Media, Serum-Free; D004791:Enzyme Inhibitors; D015221:Potassium Channels; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D016590:Aphidicolin; D014212:Tretinoin; D015544:Inositol 1,4,5-Trisphosphate; D001973:Bromodeoxyuridine; D011188:Potassium; D002118:Calcium; D005472:Fluorouracil