Warm cells revealed by microfluorimetry of Ca2+ in cultured dorsal root ganglion neurons.
Warm cells were identified by Fura-PE3-based microfluorimetry of Ca2+ in cultured dorsal root ganglion (DRG) neurons. In response to a physiologically relevant stimulus temperature (43 degrees C), a subpopulation of small DRG neurons from new born rats increased the intracellular Ca2+ concentration ([Ca2+]i). Seven percent of the cells responded to the warm stimulus. The stimulus evoked elevation in [Ca2+]i from 52.5 +/- 9.5 nM (mean +/- S.D., n = 18) to 171.0 +/- 15.6 nM in cells between 15 and 25 microns in diameter. The depletion of extracellular Ca2+ diminished the Ca2+ elevation. The Na(+)-free condition also diminished the response. We concluded that the heat stimulation opens nonselective cation channels in putative warm cells from DRG neurons.
Gotoh
H
H
Department of Bioengineering, Faculty of Engineering, Soka University, Tokyo, Japan. hideki@t.soka.ac.jp
Akatsuka
H
H
Suto
K
K
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D005456:Fluorescent Dyes; D005470:Fluorometry; D016257:Fura-2 / Q000031:analogs & derivatives; D005727:Ganglia, Spinal / Q000166:cytology / Q000502:physiology*; D006358:Hot Temperature; D007425:Intracellular Membranes / Q000378:metabolism; D009474:Neurons / Q000502:physiology*; D009994:Osmolar Concentration; D051381:Rats; D012964:Sodium / Q000378:metabolism; D013697:Thermosensing / Q000502:physiology*
D005456:Fluorescent Dyes; C098106:fura-PE3; D012964:Sodium; D002118:Calcium; D016257:Fura-2