Rates of DNA and protein syntheses by fibroblast cultures in the presence of various glucose concentrations.

Fibroblast cells derived from human derm used between the 5th and 10th passage and submitted to an increase of over 16.5 mM in the glucose concentration of the medium, react by a decrease in the incorporation of [3H] thymidine into DNA. The intracellular proline pool is largely increased by the rise in glucose concentration while the incorporation of [U-14C] proline into total proteins and proteins digested by purified bacterial collagenase is also significantly enhanced. There is no specific effect on collagen synthesis and the apparent activation of total protein synthesis may depend on the enhancement of the free proline pool.