Effects of 3-acetylpyridine on the central nervous system of the rat, as demonstrated by silver methods

The effects of acute intoxication by 3-acetylpyridine on the central nervous system of rats were investigated by means of the so-called suppressive silver impregnation methods. Consequential to a single intraperitoneal injection of this nicotinamide antagonist, partial degeneration of the facial and hypoglossal nuclei was observed, as well as total destruction of the inferior olivary complex and an almost complete destruction of the nucleus ambiguus. Accordingly, the fiber tracts originating in these structures contained degenerating fibers. All the degenerating fibers originating in the inferior olives were found to take the course of the olivo-cerebellar tracts. Degenerating fibers were also found in the solitary tracts, indicating lesions in the ganglia of origin of the visceral afferent components of the cranial nerves VII, IX and X. Discrete lesions were also detected in the substantia nigra, the nucleus of the basal optic root, and the nucleus dorsalis of the raphe in the midbrain. These observations were discussed in the light of previous data from the literature. It was concluded that the clinical symptoms observed in the treated animals were due mainly to cerebellar function impairment following inferior olive destruction. © 1974.SCOPUS: ar.j