MOLECULAR MOTOR AND ELECTROKINETIC CONTRIBUTIONS TO OUTER HAIR CELL ELECTROMOTILITY

Molecular motor and electrokinetic contributions to outer hair cell el ectromotility. J. Neurophysiol. 79: 471-473, 1998. The outer hair cell of the inner ear is believed to be responsible for the high sensitivi ty and selectivity of mammalian hearing. Molecular motors are generall y believed to cause the electrically-driven length change (electromoti lity) of the outer hair cell. It has been suggested that electrokineti c effects might also play a significant role in electromotility, along with the molecular motors. This paper describes a new technique that can be used to experimentally determine the percentage of the electrom otile response that is caused by electrokinetic effects. The technique is based on the novel idea that molecular motor activity cannot in it self generate a net force on the cell, but that electrokinetic effects can. Our method is the first that can separate molecular motor behavi or from electrokinetic behavior, during experiments on the outer hair cell.