title: Immunohistochemical localization of the pro-peptide processing enzymes PC1/PC3 and PC2 in the human anal canal.
abstract: The distribution of prohormone/pro-peptide convertases PC1/PC3 and PC2 was investigated in the human anal canal by immunohistochemistry. Both prohormone convertases exhibited region-specific distribution patterns and were observed in neural and neuroendocrine cells and in nonneuroendocrine cellular elements. PC1/PC3 immunoreactivity was present in enteric neurons, subsets of nerve fibers, and neuroendocrine cells, and also in epithelial cells like intestinal stem cells, and a subpopulation of squamous cells. Enteric neurons were PC2 immunoreactive, whereas PC2 immunostaining in nerve fibers was slightly above background levels. Few neuroendocrine cells contained PC2 immunoreactivity, which were located predominantly in the anal transitional zone. In the squamous epithelium, the basal cell layer stained for PC2. The tissue-specific distribution of PC1/PC3 and PC2 indicates region-specific processing of peptides with regulatory functions in the anal canal and further supports the hypothesis that neuropeptides are important regulators of anal functions.
authors.affiliation: Institute of Anatomy, Johannes Gutenberg University, Mainz, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Hörsch
authors.forename: R
authors.initials: R
authors.lastname: Day
authors.forename: N G
authors.initials: NG
authors.lastname: Seidah
authors.forename: E
authors.initials: E
authors.lastname: Weihe
authors.forename: M K
authors.initials: MK
authors.lastname: Schäfer
mesh_terms: D001003:Anal Canal / Q000737:chemistry / Q000201:enzymology* / Q000276:immunology; D016282:Aspartic Acid Endopeptidases / Q000737:chemistry* / Q000276:immunology; D053379:Chromogranin A; D002864:Chromogranins / Q000737:chemistry / Q000276:immunology; D019085:Fluorescent Antibody Technique, Direct; D006801:Humans; D007124:Immunoenzyme Techniques; D009363:Neoplasm Proteins / Q000737:chemistry / Q000276:immunology; D009474:Neurons / Q000737:chemistry / Q000201:enzymology / Q000276:immunology; D009479:Neuropeptides / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D009490:Neurosecretory Systems / Q000737:chemistry / Q000201:enzymology / Q000276:immunology; D045706:Proprotein Convertase 2; D043484:Proprotein Convertases; D013381:Subtilisins / Q000737:chemistry* / Q000276:immunology
chemical_list: D053379:Chromogranin A; D002864:Chromogranins; D009363:Neoplasm Proteins; D009479:Neuropeptides; D043484:Proprotein Convertases; D013381:Subtilisins; D045706:Proprotein Convertase 2; D016282:Aspartic Acid Endopeptidases