CELL LOSS IN SENSORY GANGLIA AFTER PERIPHERAL-NERVE INJURY - AN ANATOMICAL TRACER STUDY USING LECTIN-COUPLED HORSERADISH-PEROXIDASE IN CATS

In 33 adult cats the lateral superficial branch of the radial nerve wa s exposed and transsected on one side. In one group of animals (n = 22 ) the nerve-stumps were re-approximated with epineural sutures and in the other group (n = 11) the proximal nerve stump was enclosed to prev ent regeneration. After survival periods ranging from 4-17 months the same nerve on both sides was exposed to an intra-axonal nerve tracer t o label the dorsal root ganglion neurones projecting into the nerve be ing investigated. In each animal the opposite side was used as control . When the transsection was followed by a nerve suture the mean propor tion of labelled sensory neurones in the dorsal root ganglion, compare d with the control side, was 61% at eight months after operation, but by 17 months it had increased to 70%. When regeneration was prevented by the proximal nerve stump being enclosed in a plastic envelope, the reduction in labelled cells was 45% after a survival period of 17 mont hs.