FACTORS INFLUENCING THE LENGTH CHANGE OF AN AUDITORY OUTER HAIR CELL IN A TIGHT-FITTING CAPILLARY

A membrane theory with area and shear moduli is used to interpret an e xperimental configuration used by Zenner et al. [Acta Otolaryngol. 112 , 248-253]. In that experiment an outer hair cell is drawn into a tigh t-fitting glass capillary and a negative pressure is applied to charac terize the elasticity of the cell. Various assumptions concerning memb rane permeability and wall friction, which cannot readily be evaluated , are needed to interpret the data obtained in that experiment. For th is reason only an upper bound of the elastic moduli, corresponding to vanishing wall friction and basal end flow conductance, can be obtaine d from their experimental design. In this limit, the experimental data obtained by Zenner et al. do not contradict the values of elastic mod uli previously determined by internal pressurization of the cell.