Thermal influence on intracellular calcium concentration in vestibular hair cells isolated from the guinea pig. A preliminary report.
Caloric responses to intracellular calcium homeostasis of vestibular hair cells isolated from the guinea pig were examined. An increase in intracellular free calcium ion concentration ([Ca2+]i) in the isolated cells was observed by direct heat stimulation. The cells, dissociated enzymatically or mechanically, were stimulated by perfusion of solution, in the temperature range of 2.2-5.2 degrees C. The [Ca2+]i was analysed using a digital imaging microscope and the Ca2+ sensitive dye, Fura-2. There was an increase in [Ca2+]i in both Types I and II vestibular hair cells with this heat stimulation. The direct thermal influence on vestibular sensory cells is discussed in relation to mechanisms involved in caloric nystagmus.
Department of Otolaryngology, Kansai Medical University, Osaka, Japan.
M
M
Ohtani
T
T
Yamashita
H
H
Amano
N
N
Kubo
T
T
Kumazawa
D000818:Animals; D001833:Body Temperature Regulation / Q000502:physiology*; D002118:Calcium / Q000502:physiology*; D015220:Calcium Channels / Q000502:physiology*; D002150:Caloric Tests; D006168:Guinea Pigs; D007424:Intracellular Fluid / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology; D009760:Nystagmus, Physiologic / Q000502:physiology*; D014725:Vestibular Nerve / Q000502:physiology*; D014722:Vestibule, Labyrinth / Q000294:innervation*
D015220:Calcium Channels; D002118:Calcium