Alteration of cytosolic calcium levels in PC12 cells by potassium cyanide.
The effect of KCN on cytosolic Ca2+ levels was measured in PC12 cells using Quin II/AM, a fluorometric calcium indicator. The resting cytosolic Ca2+ concentration, 115.0 +/- 4.9 nm, increased gradually and steadily over a 30-min time period following addition of 10(-4), 10(-3), or 10(-2)M KCN to the cells. After 15 min, 10(-3) and 10(-2)M KCN produced a three- and sixfold increase in the cytosolic Ca2+ concentration, respectively. In K+-depolarized cells, KCN induced a more rapid rise of intracellular calcium than in cells treated with KCN or KCI alone. KCN and/or K+-induced accumulation of cytosolic Ca2+ was blocked when the cells were pretreated with 10(-5)M diltiazem (a calcium channel blocker). These results demonstrate in a cell model that cyanide induces an accumulation of cytosolic Ca2+ and this additional cytosolic Ca2+ load appears to originate primarily from the extracellular compartment. This study supports previous reports implicating calcium as an intracellular mediator of cyanide toxicity.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003486:Cyanides / Q000494:pharmacology*; D003600:Cytosol / Q000187:drug effects* / Q000378:metabolism; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D011189:Potassium Chloride / Q000494:pharmacology; D011190:Potassium Cyanide / Q000494:pharmacology*; D013050:Spectrometry, Fluorescence
D003486:Cyanides; D011189:Potassium Chloride; D011190:Potassium Cyanide; D002118:Calcium