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Jonathan Ashmore

Department of Neuroscience, Physiology & Pharmacology

Cochlear hair cells and hearing

This laboratory has wide ranging interest in cellular mechanisms of the inner ear. The research includes investigation of mechanical sound amplification in the cochlea arising from a specialized class of cellular motors, the outer hair cells; the pharmacology of a novel cholinergic synapse, the efferent synapse; the neuromodulatory action of purines in the auditory and vestibular systems and techniques of cell immortalization applied to the inner ear. The emphasis of the laboratory is on the application to hearing of biophysical methods, linked to modern cell biology.


Synaptic processing in the mammalian cochlea. The purpose of this project is to study the synaptic mechanisms in auditory hair cells, which in the case of mammalian inner hair cells, are specialised to signal sound frequencies up to 4kHz (critical for sound localization). How this fast synapse operates and how mechano-transduction processes are linked to transmitter release is not known. The technologies employed will include patch clamp and membrane capacitance measurement to study secretion processes, and fluorescence imaging to localize protein recycling


Tunstall MJ., Gale JE and Ashmore JF., (1995)
Action of salicylate on membrane capacitance of outer hair cells from the guinea pig cochlea.
Journal of Physiology 485, 739-752.

Mammano F., Kros CJ., and Ashmore JF., (1995)
Patch-clamped responses from outer hair cells in the intact organ of Corti.
Pflugers Archive - European Journal of Physiology 430: 745 - 750.

Mammano F and Ashmore JF., (1993)
Reverse transduction measured in the isolated cochlea by laser Michelson interferometry.
Nature 365 838-841

Bouvier, M., Szatkowski, M., Amato, A. & Attwell, D., (1992)
The glial cell glutamate uptake carrier counter-transports pH-changing anions.
Nature 360, 471-474.


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