Changes in macromolecular components of prolapsed intervertebral discs.

Significant quantitative differences between macromolecular components of the nuclei pulposi of prolapsed human intervertebral discs and those taken at necropsy were found. The nuclei pulposi of prolapsed discs contained about twice more collagen in comparison to control tissues. The amount of type I and type III collagens grew in a higher degree in comparison to type II of this protein. A distinctly higher solubility of the prolapsed discs collagen, together with an increased aldehyde content in solubilized collagen fractions were observed. A distinct decrease in the amount of glycosaminoglycans, especially CH-4-S and CH-6-S were found. Furthermore, a significant increase in elastin content and its susceptibility to the proteolytic action of elastase were found. The significance of these phenomena for pathobiochemistry of disc prolapse is discussed.