title: Evaluation of the protective effects of PACAP with cell-specific markers in ischemia-induced retinal degeneration.
abstract: Pituitary adenylate cyclase activating polypeptide (PACAP) is a neurotrophic and neuroprotective peptide that has been shown to exert protective effects in different neuronal injuries, such as traumatic brain injury, models of neurodegenerative diseases and cerebral ischemia. We have provided evidence that PACAP is neuroprotective in several models of retinal degeneration in vivo. In our previous studies we showed that PACAP treatment significantly ameliorated the damaging effects of permanent bilateral common carotid artery occlusion (BCCAO). In the present study cell-type-specific markers were used in the same models in order to further specify the protective effects of PACAP. In rats BCCAO led to severe degeneration of all retinal layers that was attenuated by PACAP (100 pmol) administered unilaterally immediately following BCCAO into the vitreous body of one eye. Retinas were processed for immunohistochemistry after 3 weeks. Immunolabeling was executed for vesicular glutamate transporter 1 (VGLUT 1), vesicular gamma-aminobutyric acid transporter (VGAT), protein kinase Calpha (PKCalpha), glial fibrillary acidic protein (GFAP) and calcium-binding proteins, such as calbindin, calretinin, parvalbumin. In BCCAO retinas, intensity of immunopositivity for all antisera was dramatically decreased, except in the case of GFAP. In PACAP-treated retinas, immunostaining was similar to that of the control animals. In summary, our study presented immunohistochemical identification of cell types sensitive to chronic retinal hypoperfusion and the protective effects of PACAP. This analysis revealed that the retinoprotective effects of PACAP are not phenotype-specific, but it rather influences general cytoprotective pathways irrespective of the neuronal subtypes in the retina subjected to chronic hypoperfusion.
authors.affiliation: Department of Experimental Zoology and Neurobiology, University of Pecs, Pecs, Hungary. attam@gamma.ttk.pte.hu
authors.forename: Tamas
authors.initials: T
authors.lastname: Atlasz
authors.forename: Krisztina
authors.initials: K
authors.lastname: Szabadfi
authors.forename: Peter
authors.initials: P
authors.lastname: Kiss
authors.forename: Andrea
authors.initials: A
authors.lastname: Tamas
authors.forename: Gabor
authors.initials: G
authors.lastname: Toth
authors.forename: Dora
authors.initials: D
authors.lastname: Reglodi
authors.forename: Robert
authors.initials: R
authors.lastname: Gabriel
mesh_terms: D000818:Animals; D002340:Carotid Artery Diseases / Q000150:complications / Q000188:drug therapy / Q000378:metabolism; D017536:Carotid Artery, Common; D004195:Disease Models, Animal; D007150:Immunohistochemistry; D007511:Ischemia / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D018696:Neuroprotective Agents / Q000627:therapeutic use*; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D012160:Retina / Q000187:drug effects / Q000378:metabolism; D012162:Retinal Degeneration / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D016896:Treatment Outcome; D014822:Vitreous Body / Q000187:drug effects
chemical_list: D018696:Neuroprotective Agents; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide