BACKGROUND/AIM: Alpha-2alpha adrenergic receptor (alpha(2)-AR) agonists are thought to be neuroprotective, preventing retinal ganglion cell death independent of pressure reduction. Previous studies have identified alpha(2)-ARs in rat retina. The authors aimed to demonstrate the presence and localisation of alpha(2)-ARs in human and rat retina and on the rat retinal ganglion cell line, RGC-5. METHODS: Seven postmortem human and three postmortem rat eyes were paraformaldehyde fixed and frozen. RGC-5 cells were also paraformaldehyde fixed. The expression of alpha(2A)-ARs was determined by antibody immunofluorescence. RESULTS: alpha(2A)-AR expression was identified in the human retina, on ganglion cells, and cells in the inner and outer nuclear layers (INL, ONL). Differential alpha(2A)-AR staining patterns in the INL and ONL suggest a further restriction to as yet unidentified neuronal subclasses. The RGC-5 cell line also expressed alpha(2A)-ARs in undifferentiated cells and an increased expression upon fully differentiated cells. CONCLUSION: alpha(2)-AR agonists in addition to their pressure lowering effects in the eye, may act directly upon retinal neurons, including retinal ganglion cells. The presence of alpha(2)-ARs on the RGC-5 cell line allows future investigation of these possible direct effects using in vitro glaucoma model systems.
BACKGROUND/AIM: Alpha-2alpha adrenergic receptor (alpha(2)-AR) agonists are thought to be neuroprotective, preventing retinal ganglion cell death independent of pressure reduction. Previous studies have identified alpha(2)-ARs in rat retina. The authors aimed to demonstrate the presence and localisation of alpha(2)-ARs in human and rat retina and on the rat retinal ganglion cell line, RGC-5. METHODS: Seven postmortem human and three postmortem rat eyes were paraformaldehyde fixed and frozen. RGC-5 cells were also paraformaldehyde fixed. The expression of alpha(2A)-ARs was determined by antibody immunofluorescence. RESULTS: alpha(2A)-AR expression was identified in the human retina, on ganglion cells, and cells in the inner and outer nuclear layers (INL, ONL). Differential alpha(2A)-AR staining patterns in the INL and ONL suggest a further restriction to as yet unidentified neuronal subclasses. The RGC-5 cell line also expressed alpha(2A)-ARs in undifferentiated cells and an increased expression upon fully differentiated cells. CONCLUSION: alpha(2)-AR agonists in addition to their pressure lowering effects in the eye, may act directly upon retinal neurons, including retinal ganglion cells. The presence of alpha(2)-ARs on the RGC-5 cell line allows future investigation of these possible direct effects using in vitro glaucoma model systems.
Authors: M Vidal-Sanz; M P Lafuente; S Mayor-Torroglosa; M E Aguilera; J Miralles de Imperial; M P Villegas-Pérez Journal: Eur J Ophthalmol Date: 2001 Jul-Sep Impact factor: 2.597
Authors: James R Johnson; Brandon Kocher; Edward M Barnett; Jayne Marasa; David Piwnica-Worms Journal: Bioconjug Chem Date: 2012-08-30 Impact factor: 4.774
Authors: R Scott Duncan; Daryl L Goad; Michael A Grillo; Simon Kaja; Andrew J Payne; Peter Koulen Journal: Molecules Date: 2010-03-03 Impact factor: 4.411
Authors: Leoné Malan; Mark Hamer; Roland von Känel; Konstantin Kotliar; Roelof D van Wyk; Gavin W Lambert; Walthard Vilser; Tjalf Ziemssen; Markus P Schlaich; Wayne Smith; Martin Magnusson; Annemarie Wentzel; Carlien E Myburgh; Hendrik S Steyn; Nico T Malan Journal: Cardiovasc J Afr Date: 2020-10-26 Impact factor: 1.167