Changes in permeability of articular cartilage in experimental lathyrism.

Articular cartilage does not contain blood vessels, the nutrition of chrondrocytes being derived mainly by diffusion of synovial fluid (Stockwell and Barnett, 1964; Ekholm, 1951). It has been demonstrated that the permeability of articular cartilage diminishes with ageing (Stockwell and Barnett, 1964; Tsaltsas and Kyriazis, 1967). This change has been attributed not only to the physical changes brought about by the passage of time, but also to modifications of the chemical constituents of the matrix (Kaplan and Meyer, 1959). Verzar (1963), using mechanical and chemical means, suggested that one of the principal changes associated with ageing is the increase in cross-linking of collagen fibres. He interprets this to mean that there is an increase in the degree of maturation of this protein. Experimental lathyrism, on the other hand, is characterized by a lack in the degree of maturation of collagen. This has been demonstrated by an increase in lathyritic tissues of immature neutral salt-soluble collagen (Levene and Gross, 1959; Gross and Levene, 1959). On the basis of these observations, it has been suggested that experimental lathyrism is the apparent antithesis of ageing in connective tissue (Bickley, 1964). The purpose of this study was to test this hypothesis, that lathyrism is indeed the antithesis of ageing, and to determine what implications a change in cartilage permeability in experimental lathyrism might have on the pathogenesis of this disease.