title: Role of caffeine-sensitive Ca2+ stores in Ca2+ signal termination in adult mouse DRG neurones.
abstract: The role of calcium stores in cytoplasmic calcium signal termination was studied in acutely isolated small and large DRG neurones from mice. Cytoplasmic calcium concentration ([Ca2+]in) was recorded using indo-1 microfluorometry and membrane potential was monitored by 'perforated' whole-cell patch-clamp. Depolarization-induced [Ca2+]in transients recovered significantly faster in large neurones than in small neurones. Caffeine was able to release Ca2+ from internal stores only in large neurones, while small neurones lacked caffeine-releasable calcium stores. Thapsigargin abolished caffeine-induced Ca2+ release and significantly slowed down recovery of depolarization-triggered [Ca2+]in transients in large neurones. We conclude that [Ca2+]in signals recover faster in large DRG neurones, at least in part due to the higher rate of Ca2+ sequestration by intracellular stores.
authors.affiliation: Bogomoletz Institute of Physiology, Kiev, Ukraine.
authors.forename: A
authors.initials: A
authors.lastname: Shmigol
authors.forename: P
authors.initials: P
authors.lastname: Kostyuk
authors.forename: A
authors.initials: A
authors.lastname: Verkhratsky
mesh_terms: D000818:Animals; D002110:Caffeine / Q000494:pharmacology*; D002118:Calcium / Q000502:physiology*; D005727:Ganglia, Spinal / Q000166:cytology / Q000187:drug effects*; D008564:Membrane Potentials / Q000502:physiology; D051379:Mice; D009475:Neurons, Afferent / Q000187:drug effects* / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D002110:Caffeine; D002118:Calcium