Abstract
There is evidence that isoprostanes (IsoPs) can regulate exogenously applied excitatory amino acid neurotransmitters in bovine retina in vitro. However, the regulation of retinal morphology and endogenous neurotransmitter levels by IsoPs is unknown. We examined the effects of intravitreally injected 8-iso-PGE2 on retinal tissue integrity and viability and amino acid neurotransmitters in bovine eye organ culture ex vivo. Exposure of bovine eyeballs to simulated experimental conditions revealed no retinal apoptosis and necrosis in TUNEL and DAPI staining and hematoxylin and eosin staining assays, respectively, and no changes in basal levels of amino acids in retina and vitreous humor Furthermore, intravitreal injection of 8-iso-PGE2 into bovine eyeballs had no effect on retinal apoptosis and integrity. Interestingly, 8-iso-PGE2 caused a concentration-dependent attenuation of retinal glutamate and its metabolite glutamine and glycine levels, while GABA was unaffected. 8-Iso-PGE2 (1 and 100 μM) significantly (P <0.001) attenuated glutamate levels by 33.9% and 48.0%, respectively. 8-Iso-PGE2 (100 μM) inhibited (P 2 can regulate retinal amino acids without inducing cell death in bovine retina ex vivo.