[Changes in the intervertebral disks in disorders of segmental blood supply of the spine].

In 50 mature Chinchilla rabbits a model of chronic insufficiency of blood supply in the lumbar vertebral bodies has been disturbed as a result of unilateral sectioning of the segmentary arteries and veins. By means of light and transmissive electron microscopy the dynamics of structural changes has been followed in tissue of the intervertebral discs for 3 months after the operative intervention. Under hypoxia in the ground substance of the pulposus++ nucleus even proteoglycans granular-filamentous network gradually develops and floccular material and transverse striated filamentous aggregates are accumulated. Notochord cells are subjected to certain degenerative changes and die. Simultaneously fibroblastic cells of the pulposus++ nucleus periphery become activated, they produce glycosaminoglycans and collagen. As a result the hydrated tissue of the pulposus++ nucleus is substituted for a newly formed fibrous cartilage. The process of fibroses in the intervertebral disc is completed in 3 months after blood circulation has been disturbed in the vertebral bodies.