title: Histochemical method for dipeptidyl aminopeptidase II with a new anthraquinonyl hydrazide substrate.
abstract: A new method for the histochemical visualization of lysosomal aminopeptidase dipeptidyl peptidase II activity (DPP II) is developed. The substrate L-Lys-L-Ala-5-chloro-1-anthraquinonylhydrazide-2HBr (Lys-Ala-CAH) is readily hydrolyzed by the enzyme to release 5-Cl-1-anthraquinonylhydrazine (CAH). The last compound is simultaneously coupled to an aromatic aldehyde, e.g. 4-nitrobenzaldehyde (p-NBA) or piperonal (3,4-methylenedioxybenzaldehyde; PPL), to form a highly insoluble deeply colored hydrazone, marking the enzyme locations. Using the new method, DPP II is successfully localyzed in tissue sections from different rat organs.
authors.affiliation: Institute of Experimental Morphology and Anthropology, Bulgarian Academy of Sciences, Sofia.
authors.forename: A
authors.initials: A
authors.lastname: Dikov
authors.forename: M
authors.initials: M
authors.lastname: Dimitrova
authors.forename: T
authors.initials: T
authors.lastname: Pajpanova
authors.forename: R
authors.initials: R
authors.lastname: Krieg
authors.forename: K J
authors.initials: KJ
authors.lastname: Halbhuber
mesh_terms: D000818:Animals; D000880:Anthraquinones / Q000737:chemistry / Q000378:metabolism*; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000032:analysis / Q000378:metabolism*; D020895:Enterocytes / Q000201:enzymology; D004822:Epididymis / Q000201:enzymology; D005260:Female; D006651:Histocytochemistry / Q000379:methods*; D006835:Hydrazones / Q000032:analysis / Q000378:metabolism; D007668:Kidney / Q000201:enzymology; D008099:Liver / Q000201:enzymology; D008264:Macrophages / Q000201:enzymology; D008297:Male; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000880:Anthraquinones; D006835:Hydrazones; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; C100151:dipeptidyl peptidase II