The influence of calcium ions on the synthesis of collagen and glycosaminoglycans in human diploid cells in culture.

Synthesis of collagen and glycosaminoglycans of skin fibroblasts derived from an adult normal male in culture under different Ca2+ concentrations were investigated. Collagen synthesis was increased in hypocalcemic culture and decreased in hypercalcemic culture. Ca ionophore A23187 added to the medium caused reduction of collagen synthesis. From these results, it was suggested that intracellular Ca2+ controlled the collagen synthesis of fibroblasts. Uronic acid measurements of cell surface glycosaminoglycans (csGAGS) showed the reduction of uronic acid contents along with an increase of Ca2+ concentration in the medium. 3H-glucosamine and 35S-SO42-incorporation into csGAGS showed that glycosaminoglycans synthesis was reduced along with the increase of Ca2+ concentration in the medium. The results from the uronic acid measurement and the radio-isotope incorporation suggested that sulfated glycosaminoglycans, which contained isuronic acid in high proportions such as dermatan sulfate and heparan sulfate were increased in csGAGS in hypocalcemic culture.