Calcium signalling in outer hair cells

Deafness Research UK awarded an equipment grant to Dr Michael Evans at Keele University to shed light on the inner-workings of sensory hair cells inside the cochlea.

[Equipment grant]

Fluorescence microscopy is a technique used in medical and biological sciences to enable high-quality images of proteins and molecules to be taken. Dr Evans is using the technique to learn more about the role of calcium, a crucial part of the chemical signalling pathway that enables cells in the inner ear to process sound.

Previous research has shown that calcium modifies the ability of outer hair cells to amplify sound signals. The main aim of this project is to assess the part played by calcium in down-regulating the outer hair cell response at the synapse (the point at which communication occurs between a cell and its neighbour).

A secondary aim is to discover whether this process has any effect on the “hairs” of the hair cell during the conversion from mechanical sound signal into electrical impulse.

Finally, the amount of calcium present in the cells during prolonged activity will be monitored. Calcium can be toxic to cells if it is present inside the cell at relatively high concentration and there is some evidence that this could be a factor in age-related hearing loss.