Stretch Responses of Cutaneous RA Afferent Neurons in Mouse Hairy Skin

Abstract

Rapidly adapting (RA), stretch-sensitive neurons were recorded in vitro, using an isolated preparation of skin and nerve from mouse hindlimb. The skin was stretched uniaxially using a pseudo-Gaussian noise stimulus. Loads and displacements were recorded as were spike responses of single RA afferent neurons. The goal was to determine what components of the mechanical stimulus were associated with spike responses. The association between stimuli and spike responses was measured using multiple logistic regression. Spike responses were strongly associated with the rate of change of stress and weakly associated with the rate of change of strain and with stress. There was no association between spike responses and strain. There were significant memory effects associated with each variable, and memory effects differed for each variable. The maximal effect of the rate of change of stress was observed 8–12 ms prior to a spike.