title: Multiple protracted cauda equina constrictions cause deep derangement in the lumbosacral spinal cord circuitry in the dog.
abstract: Neuropathological changes of the neuronal pools and spinal cord circuitry in the lumbosacral segments were studied in a canine model of multiple protracted cauda equina constrictions. Anterograde degeneration of all sacrococcygeal and L7 dorsal root fibers was detected in S1-S3 and lower lumbar segments. A narrow degenerated gracile fascicle was found in all thoracic and cervical segments terminating in the gracile nucleus. Transneuronal degeneration of middle-sized and large neurons, located in S1-S3 and sporadically in L7 segments, was noted. Identical transneuronal degeneration was seen in a group of small neurons located in the ventralmost part of lamina VII in S1-S3 segments. Simultaneously, a terminal degeneration was detected in the lateral cervical nucleus and in the ventral posterior lateral nucleus of the ventrobasal thalamic complex. Concomitantly, a fully developed retrograde degeneration affecting motoneurons in the ventrolateral portion of the anterior horn in S1-S3 segments appeared.
mesh_terms: D000818:Animals; D002420:Cauda Equina / Q000473:pathology*; D003251:Constriction, Pathologic / Q000150:complications; D004195:Disease Models, Animal; D004285:Dogs; D007796:Laminectomy; D008161:Lumbosacral Region / Q000473:pathology*; D009408:Nerve Compression Syndromes / Q000473:pathology; D009410:Nerve Degeneration / Q000502:physiology; D013116:Spinal Cord / Q000502:physiology*; D013126:Spinal Nerve Roots / Q000473:pathology