Interferometric evaluation of collagen concentration in tendon fibers

The dry mass concentration of collagen in native rat tail tendon fibers was studied by interferometric techniques. It could be shown that the collagen concentration of rat tail tendon fibers is not constant nor does it vary uniformly with the fiber diameter. Evidence is presented that the collagen concentration shows significant oscillations as a function of diameter. In order to explain the experimental findings, a layered model is proposed for the fiber structure; age dependent changes were also studied. It seems that the fiber structure is unaltered by ageing at the supramolecular level but its functional capacities are affected and swelling is inhibited.