SPROUTING OF A-BETA FIBERS INTO LAMINA-II OF THE RAT DORSAL HORN IN PERIPHERAL NEUROPATHY

Cholera toxin beta-subunit conjugated to horseradish peroxidase was us ed to label the large myelinated (A beta) fiber input to the dorsal ho rn in a model of peripheral neuropathy induced by tight ligation of th e L5 and L6 spinal nerves. Following induction of neuropathy, A beta f ibers were present in lamina II of the ipsilateral dorsal horn, a regi on normally devoid of A beta input. This reorganization of large fiber input to the superficial dorsal horn provides some anatomical basis f or sensory changes found in this model of neuropathic pain.