Effect of cyclosporin A on Ca2+ fluxes and the rate of respiration in Ehrlich ascites tumour cells.
Cyclosporin A at micromolar concentration decreases the respiration of Ehrlich ascites tumour cells (with pyruvate as substrate) but prevents the inhibition of oxygen uptake produced by glucose or deoxyglucose (the Crabtree effect). Cyclosporin A also diminishes the increase of cytoplasmic free Ca2+ concentration elicited by deoxyglucose and almost completely abolishes this increase induced by extracellular ATP and thapsigargin but does not decrease the size of endoplasmic reticulum Ca2+ stores as revealed after addition of ionomycin. It is concluded that cyclosporin A inhibits the inositol trisphosphate-sensitive Ca2+ channel and the passive permeability of the endoplasmic reticulum to Ca2+ in Ehrlich ascites tumour cells.
Evtodienko
Y V
YV
Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region.
Teplova
V V
VV
Duszyński
J
J
Wojtczak
L
L
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002286:Carcinoma, Ehrlich Tumor / Q000188:drug therapy / Q000473:pathology*; D002412:Cations; D016572:Cyclosporine / Q000494:pharmacology*; D003847:Deoxyglucose / Q000494:pharmacology; D004140:Dinitrophenols / Q000494:pharmacology; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D011522:Protons; D014407:Tumor Cells, Cultured
D002412:Cations; D004140:Dinitrophenols; D007476:Ionophores; D011522:Protons; D016572:Cyclosporine; D003847:Deoxyglucose; D005947:Glucose; D002118:Calcium