title: Immunohistochemical analysis of angiotensin converting enzyme in Sardinian pterygium.
abstract: Pterygium is a common ocular surface disorder characterized by excessive cell proliferation, inflammation, fibrosis, angiogenesis and extracellular matrix remodeling. The Angiotensin converting enzyme (ACE or ACE I) is the major component of the Renin-angiotensin system (RAS) converting the inactive decapeptide Angiotensin I (Ang I) to the active octapeptide Angiotensin II (Ang II). Besides this 'classical role', it can act as transcriptional regulator in response to external stimuli that may lead to cell damage and tissue remodeling. Due to this role, it can be internalized into the nuclear compartment to act as transcriptional factor for proteins involved in the inflammatory response. The aim of the present study was to determine ACE expression and localization in pterygium and culture pterygium cells by immunohistochemistry. Our results are the first to demonstrate nuclear immunolocalization of ACE, more so in pterygium compared to conjunctiva epithelial cells in histological sections. ACE was not detected in the nuclei of subcultivated pterygium epithelial cells. The nuclear localization of ACE may be correlated with an anti-inflammatory path mediated by activation of its transcriptional role.
authors.affiliation: Department of Cytomorphology, University of Cagliari Medical School, Cagliari, Italy. pdemurtas@unica.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Demurtas
authors.forename: Nick
authors.initials: N
authors.lastname: Di Girolamo
authors.forename: Michela
authors.initials: M
authors.lastname: Corrias
authors.forename: Ignazio
authors.initials: I
authors.lastname: Zucca
authors.forename: Cristina
authors.initials: C
authors.lastname: Maxia
authors.forename: Andrea
authors.initials: A
authors.lastname: Diana
authors.forename: Franca
authors.initials: F
authors.lastname: Piras
authors.forename: Simone
authors.initials: S
authors.lastname: Lai
authors.forename: Paola
authors.initials: P
authors.lastname: Sirigu
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Perra
mesh_terms: D000328:Adult; D002467:Cell Nucleus / Q000201:enzymology / Q000473:pathology; D002478:Cells, Cultured; D003228:Conjunctiva / Q000201:enzymology / Q000473:pathology; D004847:Epithelial Cells / Q000201:enzymology / Q000473:pathology; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*; D011625:Pterygium / Q000201:enzymology* / Q000473:pathology / Q000601:surgery; D012084:Renin-Angiotensin System / Q000502:physiology*
chemical_list: D007703:Peptidyl-Dipeptidase A