The in vitro biosynthesis of collagen in bovine heart valves

Bovine heart valves of different ages were incubated with l -proline-3H for the study of collagen biosynthesis. The synthesis of collagen in the heart valves, especially in the young, is quite active. The specific activity of hydroxyproline in collagen in all heart valves decreased with increasing age. The biosynthetic activity in the mitral valve was higher than in that of the other cardiac valves. The specific activity of hydroxyproline in the fibroblast-rich portion of the old bovine heart valve was comparatively higher than in the chondroblast-rich portion. With the in vitro system, radioactivity was detected in insoluble fibrous collagen in the heart valve. The effect of several chelating agents on collagen biosynthesis was studied. BAL, neocuproine, and a,a′-dipyridyl inhibited collagen biosynthesis completely at high concentrations (10−3, m ). On the other hand, EDTA and semicarbazide had very little effect.