TY - JOUR T1 - Immunohistochemical Localization of the Acylases that Catalyze the Deacetylation of <em>N</em>-Acetyl-<span class="sc">l</span>-cysteine and Haloalkene-Derived Mercapturates JF - Drug Metabolism and Disposition JO - Drug Metab Dispos SP - 625 LP - 632 VL - 28 IS - 6 AU - Vinita Uttamsingh AU - Raymond B. Baggs AU - Daria M. Krenitsky AU - M. W. Anders Y1 - 2000/06/01 UR - http://dmd.aspetjournals.org/content/28/6/625.abstract N2 - Acylases catalyze the hydrolysis of a range ofS-substitutedN-acetyl-l-cysteines. The hydrolysis ofN-acetyl-l-cysteine is catalyzed by cytosolic acylase I, and activity is present in human endothelial cells and rat lung, intestinal, and liver homogenates. Many haloalkenes are metabolized to mercapturates, which also undergo acylase-catalyzed hydrolysis. The acylases that catalyze the deacetylation ofN-acetyl-l-cysteine and several haloalkene-derived mercapturates have been recently identified: acylase I catalyzes the deacetylation ofN-acetyl-l-cysteine and some haloalkene-derived mercapturates whereas an acylase purified from rat kidney cytosol catalyzes the deacetylation of a distinct set of substrates, including several haloalkene-derived mercapturates. The objective of these studies was to examine the tissue and subcellular localization of acylase I and purified rat kidney acylase. Immunoblotting showed the presence of immunoreactive acylase I and purified rat kidney acylase in rat kidney, liver, lung, and brain. Both acylases were identified by immunohistochemistry in several rat organs, including kidney, liver, lung, brain, stomach, intestines, adrenals, pancreas, and testis, indicating that acylase activity is widespread in rat tissues. The American Society for Pharmacology and Experimental Therapeutics ER -