Mechanisms of Electrical Membrane Responses in Sensory Receptors, Illustrated by Mechanoreceptors

Abstract

Biochemical investigation of sensory transduction within receptor cells has to envisage the fact that these processes are performed by functional systems consisting of a number of sub-mechanisms of quite different nature. This diversity corresponds to a highly differentiated structural organization of the transducing region of the cell. In a type of receptor cell in which the functional and structural organization had originally appeared rather “isotropic”, i.e. in the Pacinian corpuscle, further investigation has also revealed a high level of structural complexity (Fig. 5A) [1]. The structural heterogeneity of the transducing regions need not handicap biochemical investigation but may actually be advantageous, since a spatial separation of the submechanisms facilitates a dissection of the functional complex so that the submechanisms can be studied separately. The following contribution is an attempt to outline principles of the functional organization of sensory receptor cells in order to give a framework of understanding for further investigation of the various functional elements and their interrelationship.