Spatial and dye correlation analysis of intracellular Ca2+ distribution.
Intracellular Ca2+ is an important regulator of many cellular processes. Besides ion channels and transporters in the plasmalemma, changes in [Ca]i can be mediated by uptake and release mechanisms of internal organelles. Theoretical and experimental procedures are developed aiming to reveal the distribution of internal Ca2+ pools and their role in generating complicated spatial patterns of [Ca]i gradients. Cultured pyramidal neurons from rat hippocampus were loaded with Ca(2+)-sensitive fluorescent dyes, fura-2 and fluo-3. Cell images were partitioned according to pixel amplitude and highlighted pictures were characterized by their intensity, relative area and connectivity. This approach facilitates the localization of the sites of Ca2+ release from internal stores induced by application of different agents. After each trial, neurons were stained with dyes, acridine orange or DiOC6, which bind preferentially to nucleus and endoplasmic reticulum. A correlation between images confirmed the spatial localization of Ca2+ release sites. Application of the partition procedure also gave a clear evidence for the importance of Ca2+ influx in the mechanism of [Ca]i oscillations.
Mironov
S L
SL
University of Salzburg, Department of Animal Physiology, Austria.
Hermann
A
A
D000814:Aniline Compounds; D000818:Animals; D000831:Animals, Newborn; D002110:Caffeine / Q000494:pharmacology; D002118:Calcium / Q000032:analysis / Q000378:metabolism*; D002232:Carbocyanines; D002478:Cells, Cultured; D004622:Embryo, Mammalian; D005456:Fluorescent Dyes; D016257:Fura-2; D006624:Hippocampus / Q000378:metabolism*; D018613:Microscopy, Confocal / Q000379:methods; D017966:Pyramidal Cells / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D014966:Xanthenes
D000814:Aniline Compounds; D002232:Carbocyanines; D005456:Fluorescent Dyes; D014966:Xanthenes; C059715:Fluo-3; D002110:Caffeine; C007392:3,3'-dihexyl-2,2'-oxacarbocyanine; D002118:Calcium; D016257:Fura-2