PURPOSE: Nitric oxide synthase (NOS) plays an essential role in neuronal function and is critical in the brain for normal and pathologic responses to glutamate. The role of NOS in the retina is less well understood. The retina provides an experimental system in which the intrinsic circuitry is well defined; retinal excitotoxic damage has been well characterized. METHODS: To determine whether neuronal NOS (nNOS) and endothelial NOS (eNOS) are critical in excitotoxic damage in the retina, nNOS- and eNOS-deficient mice were subjected to intravitreal injections of N-methyl-D-aspartate (NMDA) or to arterial occlusions. RESULTS: Retinal ganglion cells in the nNOS-deficient mouse were relatively resistant to NMDA and to arterial occlusion. In contrast, the damage in the eNOS-deficient mouse retina was not distinguishable from that in control animals. Preinjection with an NOS inhibitor was partially protective. CONCLUSIONS: The presence of nNOS is a prerequisite for the full expression of excitotoxicity in the retina; eNOS does not appear to play a significant role.
PURPOSE:Nitric oxide synthase (NOS) plays an essential role in neuronal function and is critical in the brain for normal and pathologic responses to glutamate. The role of NOS in the retina is less well understood. The retina provides an experimental system in which the intrinsic circuitry is well defined; retinal excitotoxic damage has been well characterized. METHODS: To determine whether neuronal NOS (nNOS) and endothelial NOS (eNOS) are critical in excitotoxic damage in the retina, nNOS- and eNOS-deficient mice were subjected to intravitreal injections of N-methyl-D-aspartate (NMDA) or to arterial occlusions. RESULTS: Retinal ganglion cells in the nNOS-deficient mouse were relatively resistant to NMDA and to arterial occlusion. In contrast, the damage in the eNOS-deficient mouse retina was not distinguishable from that in control animals. Preinjection with an NOS inhibitor was partially protective. CONCLUSIONS: The presence of nNOS is a prerequisite for the full expression of excitotoxicity in the retina; eNOS does not appear to play a significant role.
Authors: Giselle Foureaux; José C Nogueira; Bárbara S Nogueira; Gustavo O Fulgêncio; Gustavo B Menezes; Simone O A Fernandes; Valbert N Cardoso; Renata S Fernandes; Gabriel P Oliveira; Juçara R Franca; André A G Faraco; Mohan K Raizada; Anderson J Ferreira Journal: Invest Ophthalmol Vis Sci Date: 2013-06-21 Impact factor: 4.799
Authors: Nanna Vestergaard; Lasse Jørgensen Cehofski; Bent Honoré; Kristian Aasbjerg; Henrik Vorum Journal: Transl Vis Sci Technol Date: 2019-08-15 Impact factor: 3.283
Authors: Mi Sun Sung; Hwan Heo; Gwang Hyeon Eom; So Young Kim; Helong Piao; Yue Guo; Sang Woo Park Journal: Int J Mol Sci Date: 2019-10-17 Impact factor: 5.923