title: Original method for the histochemical demonstration of tripeptidyl aminopeptidase I.
abstract: The original histochemical method for the visualization of tripeptidyl aminopeptidase I (TPP I, EC 3.4.14.9) is developed. The method is based on the new synthetic substrates Gly-L-Pro-L-Met(or L-Ala)-5-chloro-1-anthraquinonyl hydrazide (Gly-Pro-Met[Ala]-CAH). The final reaction product is represented as tripeptidyl-5-chloro-1 anthraquinonyl hydrazides (TPP-CAH). Upon the enzyme action the practically in aqueous media insoluble brown-reddish dye 5-chloro-1-anthraquinonyl hydrazine (CAH) is released, which reacts simultaneously with aromatic aldehydes as e.g. 4-anisaldehyde (p-AA) or 4-nitrobenzaldehyde (p-NBA), resulting in microcrystalline or amorphous deeply colored hydrazones. The last compounds mark accurately the locations of enzymatic activity. The biochemically suggested lysosomal localization of this collagen-degrading exopeptidase is thus confirmed on tissue sections. More information about the distribution of TPP I in different rat organs is presented as well.
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: I
authors.initials: I
authors.lastname: Ivanov
authors.forename: R
authors.initials: R
authors.lastname: Krieg
authors.forename: K J
authors.initials: KJ
authors.lastname: Halbhub
mesh_terms: D000626:Aminopeptidases; D000818:Animals; D000880:Anthraquinones / Q000737:chemistry / Q000378:metabolism; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; D010450:Endopeptidases / Q000032:analysis* / Q000378:metabolism*; D004822:Epididymis / Q000201:enzymology; D005260:Female; D006651:Histocytochemistry / Q000379:methods*; D006835:Hydrazones / Q000032:analysis / Q000378:metabolism; D007668:Kidney / Q000201:enzymology; D008099:Liver / Q000201:enzymology; D008168:Lung / Q000201:enzymology; D008297:Male; D015394:Molecular Structure; D051381:Rats; D017208:Rats, Wistar; D057057:Serine Proteases; D013154:Spleen / Q000201:enzymology; D000091346:Tripeptidyl-Peptidase 1; D014599:Uterus / Q000201:enzymology
chemical_list: D000880:Anthraquinones; D006835:Hydrazones; C000717269:Tpp1 protein, rat; D000091346:Tripeptidyl-Peptidase 1; D010450:Endopeptidases; D057057:Serine Proteases; D000626:Aminopeptidases; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases