ENHANCED DENATURATION OF THE ALPHA-1(II) CHAINS OF TYPE-II COLLAGEN IN NORMAL ADULT HUMAN INTERVERTEBRAL DISCS COMPARED WITH FEMORAL ARTICULAR-CARTILAGE

The mechanical strength of connective tissues is dependent on the inte grity of their fibrillar collagen frameworks. The objective of the pre sent study was to assess type II collagen damage (denaturation) in the adult human intervertebral disc compared with articular cartilage, in order to determine whether damage to this molecule may vary in differ ent anatomical sites in the same person. A new immunochemical assay wa s used to measure the amounts of denatured and total type-II collagen in the annulus fibrosus and nucleus pulposus of the L5-S1 disc and in cartilage from the femoral condyles of the same individuals (n = 7). D enaturation of type-II collagen was significantly higher in both the a nnulus fibrosus and the nucleus pulposus than in articular cartilage. Such increased damage to type-II collagen in the adult disc may have r elevance to the more pronounced degenerative changes observed in this tissue compared with articular cartilage.