COLLAGENOLYTIC ACTIVITY OF INTACT AND NECROTIC CONNECTIVE TISSUE.

Isotonic saline extracts of both intact and necrotic skin of the rat were capable of releasing over 50 percent of the hydroxyproline content of soluble collagen as dialyzable, peptide-bound amino acid only after prior, limited proteolytic activation of trypsin. These "activated" extracts could also solubilize insoluble collagen to release dialyzable hydroxyproline containing peptides. This collagenolytic activity was maximal at pH 5.5 and was not inhibited by soybean trypsin inhibitor, ethyl-enediaminetetraacetic acid, or heavy metal salt. The "activated" extracts showed no general proteolytic activity toward denatured hemoglobin. The collagenolytic activity was destroyed both by heat and by extensive tryptic proteolysis.