A comparative study of the distribution of the stable crosslink, pyridinoline, in bone collagens from normal, osteoblastoma, and vitamin D-deficient chicks

Tryptic peptides of bone collagens from 4-week-old normal, osteoblastoma and vitamin D-deficient chicks were studied using gel filtration chromatography. Absorbance at 230 nm and fluorescence (excitation at 330 nm, emission at 390 nm) of each fraction were measured. The relative quantities of each peak from the absorbance and fluorescence patterns were semiquantified by planimetry. Osteoblastoma bone collagen had a prominent, fluorescent, crosslinked peptide that contained pyridinoline. Fluorescence of this pyridinoline-containing peak in AO collagen was much greater than in the vitamin D-deficient and normal bone collagen counterparts. A comparison of fluorescence patterns clearly showed that the distribution of pyridinoline in collagen from normal and diseased bone was totally dissimilar. The dissimilarities in distribution of pyridinoline in these bone collagens may be attributed to differences in the degree of lysine hydroxylation, to the degree of mineralization, or some other factor.