Thermal Influence on Intracellular Calcium Concentration in Vestibular Hair Cells Isolated from the Guinea Pig: A preliminary report

Abstract

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°. 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.

Key Words:

• Fura-2
• caloric
• heat
• temperature.