title: Immunohistochemical localization of angiotensin-converting enzyme, angiotensin II and AT1 receptor in human ocular tissues.
abstract: We investigated the immunohistochemical distribution of 3 components of the renin-angiotensin system (RAS), angiotensin-converting enzyme (ACE), angiotensin II (AngII) and AT1 receptor (AT1), in the human eye. ACE and AngII were localized to nonpigmented epithelial cells of the ciliary body, to endothelial and epithelial cells of the cornea, to epithelial cells of the conjunctiva and to trabecular meshwork cells in the anterior part of the eye. In the posterior part of the eye, ACE and AngII were localized to ganglion cells, some cells in the inner nuclear layer, photoreceptor cells and to endothelial cells of the retinal and choroidal vessels. The overall intensity of AT1 immunoreactivity was weak in all ocular tissues, but the main localization was in ganglion cells. As a preliminary investigation, we were able to include 2 Alzheimer's disease (AD) cases. In AD, no differences from controls were found in the cellular distribution and staining intensity of all 3 antigens. The manifold localization sites of the observed antigens point to rather generalized functions of the RAS in human ocular tissues, such as regulatory effects on neuronal cells, vessels and vitreous humor homeostasis.
authors.affiliation: Psychiatric University Clinic, University of Basel, Basel, Switzerland. egemen.savaskan@pukbasel.ch
authors.forename: Egemen
authors.initials: E
authors.lastname: Savaskan
authors.forename: Karin U
authors.initials: KU
authors.lastname: Löffler
authors.forename: Fides
authors.initials: F
authors.lastname: Meier
authors.forename: Franz
authors.initials: F
authors.lastname: Müller-Spahn
authors.forename: Josef
authors.initials: J
authors.lastname: Flammer
authors.forename: Peter
authors.initials: P
authors.lastname: Meyer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism*; D000804:Angiotensin II / Q000378:metabolism*; D005123:Eye / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*; D044140:Receptor, Angiotensin, Type 1 / Q000378:metabolism*; D012084:Renin-Angiotensin System; D014018:Tissue Distribution
chemical_list: D044140:Receptor, Angiotensin, Type 1; D000804:Angiotensin II; D007703:Peptidyl-Dipeptidase A