title: Depletion of intracellular Ca2+ by caffeine and ryanodine induces apoptosis of chinese hamster ovary cells transfected with ryanodine receptor.
abstract: Recent studies have suggested a central role for Ca(2+) in the signaling pathway of apoptosis and certain anti-apoptotic effects of Bcl-2 family of proteins have been attributed to changes in intracellular Ca(2+) homeostasis. Here we report that depletion of Ca(2+) from endoplasmic reticulum (ER) leads to apoptosis in Chinese hamster ovary cells. Stable expression of ryanodine receptor (RyR) in these cells enables rapid and reversible changes of both cytosolic Ca(2+) and ER Ca(2+) content via activation of the RyR/Ca(2+) release channel by caffeine and ryanodine. Sustained depletion of the ER Ca(2+) store leads to apoptosis in Chinese hamster ovary cells, whereas co-expression of Bcl-xL and RyR in these cells prevents apoptotic cell death but not necrotic cell death. The anti-apoptotic effect of Bcl-xL does not correlate with changes in either the Ca(2+) release process from the ER or the capacitative Ca(2+) entry through the plasma membrane. The data suggest that Bcl-xL likely prevents apoptosis of cells at a stage downstream of ER Ca(2+) release and capacitative Ca(2+) entry.
authors.affiliation: Departments of Physiology & Biophysics and Anatomy, Case Western Reserve University School of Medicine and the Center for Anesthesiology Research, Cleveland Clinic Foundation, Cleveland, Ohio 44106, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Pan
authors.forename: D
authors.initials: D
authors.lastname: Damron
authors.forename: A L
authors.initials: AL
authors.lastname: Nieminen
authors.forename: M B
authors.initials: MB
authors.lastname: Bhat
authors.forename: J
authors.initials: J
authors.lastname: Ma
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D016466:CHO Cells; D002110:Caffeine / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002614:Chelating Agents / Q000494:pharmacology; D002843:Chromatin / Q000187:drug effects; D006224:Cricetinae; D003600:Cytosol / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D018613:Microscopy, Confocal; D018482:Muscle, Skeletal / Q000378:metabolism; D009336:Necrosis; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D010957:Plasmids; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D011817:Rabbits; D012433:Ryanodine / Q000494:pharmacology*; D019837:Ryanodine Receptor Calcium Release Channel / Q000378:metabolism*; D013997:Time Factors; D014162:Transfection; D051020:bcl-X Protein
chemical_list: D015220:Calcium Channels; D002614:Chelating Agents; D002843:Chromatin; D018076:DNA, Complementary; D010726:Phosphodiesterase Inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2; D019837:Ryanodine Receptor Calcium Release Channel; D051020:bcl-X Protein; D012433:Ryanodine; D002110:Caffeine; D004533:Egtazic Acid; C025603:1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid; D002118:Calcium