[Regulation of the biosynthesis of macromolecules of the intercellular corneal matrix].

The influence of a 1M CaCl2 extract and of a collagenase digest of corneal stroma of the biosynthesis of the macromolecules of corneal stroma was investigated. Calf corneas were incubated "in vitro" with radioactive tracers (14C-L-proline; 3H-D-glucosamine or 35SO4) in the presence or absence of the above extracts. After incubation the corneas are submitted to a fractional extraction in order to separate the major macromolecular fractions of the stroma. An increase in incorporation of all tracers is observed in the 1M CaCl2 (CTC), TCA and urea-extracts (containing resp. the diffusible macromolecules, proteoglycans, polymeric collagen and structural glycoproteins) in the presence of the macromolecular extracts and also with the collagenase-hydrolysate of cornea. These results show the existence of a stimulation of the biosynthesis of intracellular matrix macromolecules of the cornea by corneal extracts, probably through positive "feedback" type of mechanism.