title: Inhibition of cysteine proteinase activity by Z-Phe-Phe-diazomethane and of aspartic proteinase activity by pepstatin in different organs from some animals and isolated cells from rat liver.
abstract: Two methods have been developed to discriminate simultaneously between the main part of cysteine proteinase activity (cathepsin L) and all aspartic proteinase activity (mainly cathepsin D) in rat organs, using Z-Phe-Phe-CHN2 which at 5 mumol/l completely inhibits cathepsin L from rat liver and, on the other hand, pepstatin which at 0.5 mumol/l completely inhibits cathepsin D. Substrates are double-labeled cytosol proteins from rat liver at pH 3.0 or azocasein in 3 mol/l urea at pH 5.0. Several organs from rat, pigeon, frog and carp have been investigated using these methods. Especially kidneys from rat, frog and carp contain a high Z-Phe-Phe-CHN2 inhibited activity. Investigating the different liver cell types we could confirm earlier findings that Kupffer cells and endothelial cells contain more pepstatin inhibited activity than parenchymal cells.
mesh_terms: D000818:Animals; D016282:Aspartic Acid Endopeptidases; D002347:Carps; D002401:Cathepsin B; D056668:Cathepsin L; D002403:Cathepsins / Q000037:antagonists & inhibitors; D010856:Columbidae; D003546:Cysteine Endopeptidases; D003978:Diazomethane / Q000031:analogs & derivatives* / Q000494:pharmacology; D010450:Endopeptidases / Q000378:metabolism*; D007668:Kidney / Q000201:enzymology; D008099:Liver / Q000201:enzymology*; D009206:Myocardium / Q000201:enzymology; D009842:Oligopeptides / Q000494:pharmacology*; D010436:Pepstatins / Q000494:pharmacology*; D011480:Protease Inhibitors; D011898:Ranidae; D051381:Rats; D013154:Spleen / Q000201:enzymology; D014018:Tissue Distribution
chemical_list: D009842:Oligopeptides; D010436:Pepstatins; D011480:Protease Inhibitors; D003978:Diazomethane; C022922:carbobenzoxycarbonyl-L-phenylalanyl-L-alanine-D-diazomethane; D002403:Cathepsins; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; D002401:Cathepsin B; D056668:Cathepsin L; C534280:Ctsl protein, rat; D016282:Aspartic Acid Endopeptidases