Local Responses in Pacinian Corpuscles

Abstract

The potentials of single fibers from Pacinian corpuscles of the cat''s mesentery were recorded. Monophasic recording from the point of emergence of the axon from the corpuscle has shown that subthreshold mechanical stimuli produce a local negative depolarization that has all the characteristics of the local responses descr. by Hodgkin. The following facts were observed: The local response to 2 subthreshold stimuli may summate to evoke an action potential. The magnitude of the local response to a subthreshold stimulus is decreased during the refractory period following a previous action potential. "On" and "Off" responses are evoked by long stimuli of 50 msec. duration. Multiple responses to a single stimulus are produced only when the mesentery is distended or the corpuscle is by any other means submitted to a constant pressure. These results are compared with data presented previously by other authors, and the mechanism of initiation of action potentials in Pacinian corpuscles is discussed.