Collagenase production by adult rat hepatocytes in primary culture¹

Adult rat hepatocytes were evaluated after 8 days of primary culture for their ability to produce a latent collagenase which could be activated by limited proteolysis with trypsin. The activated collagenase, like other vertebrate interstitial collagenases, cleaved native collagen in solution at neutral pH at the specific site of three-quarter distance from the N-terminus of the collagen molecule and was inactivated by the presence of EDTA, cysteine or serum. The molecular weights of the hepatocyte collagenase in latent and active forms were estimated to be 73,000 and 45,000, respectively. In early periods (2~6 days) of culture, only a trace level of collagenase activity was detected.