GROWTH-RELATED PRODUCTION OF PROTEOGLYCANS AND HYALURONIC-ACID IN SYNCHRONOUS ARTERIAL SMOOTH-MUSCLE CELLS

1. The growth-stimulating effect of serum on the proteoglycan and hyaluronic acid production in arterial smooth muscle cells was investigated, using cells synchronized by serum deprivation. 2. After stimulation, synthesis of [S-35]sulfated proteoglycans and [C-14]hyaluronic acid increased during G1 and G2 phases (about 2- and 5-fold, respectively, in the culture medium), in comparison with quiescent cells. 3. Neither the size, nor the charge, nor the relative proportions of [S-35]glycosaminoglycans of the proteoglycans were modified. 4. However, when the cells were stimulated to divide, increased synthesis of large [C-14]hyaluronic acid was observed concomitantly with the production of higher hydrodynamic size [S-35]proteoglycans, which aggregated with hyaluronic acid (20%).