Distribution of cathepsins B and H in rat tissues and peripheral blood cells.
The concentrations of cathepsins B and H in various tissues and peripheral blood cells of rats were determined by means of sensitive immunoassays. The minimum detectable amounts of cathepsins B and H were 30 pg and 20 pg/assay, respectively, and the presence of endogenous thiol proteinase inhibitors did not interfere with the immunoassays. Cathepsin B was found at high levels in the kidney, vagina, spleen, and adrenal gland, and cathepsin H at high levels in the kidney, vagina, liver, lung, and spleen. Low levels of cathepsins B and H were present in the heart, skeletal muscle, and testis. The ratios of cathepsins B and H in various organs were different: the brain and adrenal gland contained much higher levels of cathepsin B than of cathepsin H, whereas the lung and liver contained higher levels of cathepsin H than of cathepsin B. In several organs such as the kidney, spleen, liver, and lungs, the level of cathepsins B plus H was much higher than that of thiol proteinase inhibitors (TPI-alpha + TPI-beta), whereas in tissues containing large amounts of TPI-alpha, such as the skin, esophagus and stomach, the level of inhibitors was higher than that of cathepsins B plus H. Of the peripheral blood cells tested, macrophages had the highest contents of cathepsins B and H, and so their level of cathepsins B plus H was much higher than that of TPI-alpha plus TPI-beta, whereas lymphocytes and neutrophils contained comparable amounts of proteinases and inhibitors.(ABSTRACT TRUNCATED AT 250 WORDS)
D000818:Animals; D000918:Antibody Specificity; D001773:Blood Cells / Q000201:enzymology; D002401:Cathepsin B; D056655:Cathepsin H; D002403:Cathepsins / Q000378:metabolism*; D003546:Cysteine Endopeptidases; D007124:Immunoenzyme Techniques; D008099:Liver / Q000201:enzymology; D008297:Male; D011480:Protease Inhibitors / Q000378:metabolism; D051381:Rats; D014018:Tissue Distribution
D011480:Protease Inhibitors; D002403:Cathepsins; D003546:Cysteine Endopeptidases; D002401:Cathepsin B; D056655:Cathepsin H; C534128:Ctsh protein, rat