title: A latent form of collagenase in the involuting rat uterus and its activation by a serine proteinase.
abstract: 1. The involuting rat uterus displays an extremely rapid breakdown of collagen. Collagenase activity can be assayed directly in the insoluble 6000g pellet of uterine homogenates. At 1 day post partum, about 85% of this collagenase activity is in a latent form. 2. This latent form can be activated by trypsin or by a serine proteinase present in the uterine pellets. 3. The activating enzyme of the tissue is inhibited by a wide spectrum of trypsin inhibitors, including Trasylol, soya-bean and lima-bean trypsin inhibitors, snail inhibitor and di-isopropyl phosphoro-fluoridate. Partial inhibition is produced by benzamidine, phenylmethanesulphonyl fluoride, epsilon-aminohexanoate, leupeptin, antipain and alpha1-antitrypsin. Ovomucoid, 7-amino-1-chloro-3-tosylamido-1-heptan-2-one and 1-chloro-4-phenyl-3-(N-benzyloxy-carbonyl)amino-L-butan-2-one are not inhibitory. 4. Extraction of uterine pellets with 0.1 M-CaCl2 at 60 degrees C releases both latent and active collagenase. Exclusion chromatography on Sephadex G-100 gives an apparent molecular weight of approx. 77000 for the latent form and 66000 for the active form. The latent form is suggested to be a zymogen of collagenase.
mesh_terms: D000818:Animals; D010450:Endopeptidases; D004789:Enzyme Activation; D005260:Female; D003012:Microbial Collagenase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008970:Molecular Weight; D011247:Pregnancy; D051381:Rats; D014357:Trypsin; D014361:Trypsin Inhibitors / Q000494:pharmacology; D014599:Uterus / Q000201:enzymology*
chemical_list: D014361:Trypsin Inhibitors; D010450:Endopeptidases; D014357:Trypsin; D003012:Microbial Collagenase