[The cytoskeleton and mechanoreception thresholds].

Abstract

In order to analyse the mechanisms of high sensitivity of mechanoreceptors the role of cytoskeleton in the deformation of receptor membrane was considered. The later was considered as an elastic plate. Local relative deformations epsilon s near the attachment points of cytoskeleton filaments to the membrane were calculated. It is shown that at different types of deformation for small regions of the membrane with the size R of several scores of nm the epsilon s values are L/R where L is absolute displacement of the region under the effect of the force applied. For the hair cells of the corti organ the model including neighbor stereocilia connected by the skeleton filaments shows the values epsilon s approximately 10(-4). The latter by several orders exceed the values characteristic of the single stereocilium deflection. On the basis of the model calculations of epsilon s a hypothesis is advanced for Pacinian corpuscle concerning the existence of a bond between the membrane sensitive ending and the inner capsula via cytoskeleton filaments, which suggests high epsilon s values of this receptor. The cytoskeleton elements should be considered an intrinsic part of the sensitive centre.