Synthesis and turnover of collagen precursors in rabbit skin.
1. The rate of synthesis of [(14)C]hydroxyproline by rabbit skin was studied in vitro and in vivo. 2. The soluble collagen fractions were shown to have a very rapid turnover. The 0.15m-sodium chloride-extractable collagen showed t((1/2)) values of 1.2hr. in vitro and 12hr. in vivo. The 0.5m-sodium chloride-extractable collagen exhibited a t((1/2)) value of 20hr. in vivo. 3. Under the conditions used it was not possible to obtain radioactive insoluble collagen in vitro. 4. A significant amount of soluble collagen is lost before it becomes insoluble. 5. These observations may help to explain why large amounts of peptide-bound hydroxyproline appear in the urine during periods of rapid collagen synthesis.
D000818:Animals; D002247:Carbon Isotopes; D003094:Collagen / Q000096:biosynthesis*; D006909:Hydroxyproline / Q000096:biosynthesis*; D066298:In Vitro Techniques; D008297:Male; D011392:Proline / Q000378:metabolism*; D011817:Rabbits; D012867:Skin / Q000378:metabolism*; D012965:Sodium Chloride
D002247:Carbon Isotopes; D012965:Sodium Chloride; D003094:Collagen; D011392:Proline; D006909:Hydroxyproline