Stimulation of Collagen Synthesis in Embryonic Chick Skin by Insulin

The effect of insulin on collagen biosynthesis was studied using 14C proline and 14C lysine in 10 day embryonic chick skin. Insulin stimulated (in vitro) the total incorporation of both amino acids as well as the formation of 14C hydroxyproline and 14C hydroxylysine. The stimulatory effect of insulin was more pronounced with 14C proline when a 2-fold increase in 14C hydroxyproline synthesis was observed. When 14C lysine was present in the incubating medium, a 50% increment in 14C hydroxylysine formation was noted when insulin was added. Insulin had no effect on the glycosylation of newly formed hydroxylysine. Maximum stimulation by insulin occurred at 6 hours.