[Study of individual Pacinian corpuscle mechanoreceptors following application of colchicine to a nerve].

Colchicine application to the cat caudal mesenteric nerve containing sensory fibers for single mechanoreceptors (Pacinian corpuscles) causes degeneration of the axis cast of the nerve endings. Ultrastructural changes in the receptors showed no difference from the axonal degeneration after the nerve section but the rate of degeneration was considerably slower. Ultrastructural, electrophysiological, and biochemical changes occurring in the Pacinian corpuscles were not the result of direct action of colchicine, but appeared to be realized through the nerve by the axoplasmic transport block. It is suggested that the receptor's structure is under the sensory neuron neurotrophic control.