Quantitative microchemical imaging of calcium in Na-K pump inhibited heart cells.
Quantitative electron probe X-ray imaging techniques have been utilized to determine simultaneously the element content within a single cultured embryonic chick heart cell and its intracellular compartments as well as the average elemental content of several heart cells within a population. These features of microchemical imaging have permitted establishment of data regarding: (1) the heterogeneity of calcium accumulation in mitochondrial, cytoplasmic and nuclear compartments under conditions which elevate total cell calcium without producing irreversible cell injury; and (2) the variability of calcium accumulation from cell to cell within the population sampled. The results indicate that during Na-K pump inhibition (K-free HT-BSS, 10(-4) M ouabain, 60 min) elevation of mitochondrial calcium, measured in situ by electron probe X-ray microanalysis, to levels more than 100 times greater than in the basal state, may not cause irreversible mitochondrial uncoupling and cell death.
LeFurgey
A
A
Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina.
Ingram
P
P
Lieberman
M
M
D002118:Calcium / Q000032:analysis*; D004577:Electron Probe Microanalysis / Q000379:methods; D005615:Freezing; D006801:Humans; D008928:Mitochondria / Q000032:analysis / Q000378:metabolism; D009206:Myocardium / Q000032:analysis / Q000166:cytology*; D015388:Organelles / Q000032:analysis; D011309:Preservation, Biological; D000254:Sodium-Potassium-Exchanging ATPase / Q000494:pharmacology*
D000254:Sodium-Potassium-Exchanging ATPase; D002118:Calcium