Measurement of ionized calcium in normal human blood platelets.
To measure the concentrations of cytosolic ionized calcium in platelets we used a calcium-sensitive fluorophor (Fura-2) with two different spectrofluorometers (Perkin-Elmer LS-5 and Fluorolog 222). Values obtained by these two instruments for the basal cytosolic ionized calcium concentration of resting platelets and those of agonist-activated platelets did not differ significantly. Both instruments were capable of monitoring the shifts in wavelengths induced by the dye-calcium complex, the ratio between absorbances at the two wavelengths (340/380 nm), and calcium concentrations continuously during agonist-induced platelet activation. We conclude that a relatively inexpensive instrument may be adequate for measuring ionized calcium in cells by this method, although sophisticated kinetic studies may require analytical or research-grade instruments.
Rao
G H
GH
Department of Laboratory Medicine and Pathology, University of Minnesota Hospital and Clinics, Minneapolis 55455.
D000328:Adult; D001792:Blood Platelets / Q000032:analysis*; D002118:Calcium / Q000097:blood*; D003600:Cytosol / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors; D012146:Rest; D013050:Spectrometry, Fluorescence; D013917:Thrombin / Q000037:antagonists & inhibitors / Q000494:pharmacology
D010972:Platelet Activating Factor; D013917:Thrombin; D002118:Calcium