Possible antiapoptotic and neuroprotective effects of magnesium sulphate on retina in a preterm hypoxic-ischemic rat model

BACKGROUND/AIM: The effects of systemic magnesium sulfate (MgSO(4)) on retina in preterm hypoxic-ischemic (HI) rat model are not known. Our aim was to investigate the effects of MgSO(4) on retinal ganglion cell (RGC) count, retinal ganglion cell (RGC) apoptotic index, retinal vascular endothelial growth factor receptor-2 (VEGFR-2), and glial fibrillary acidic protein (GFAP) expressions in preterm HI rat model. MATERIALS AND METHODS: Fifteen, postnatal day (PND) 7 rat pups were divided into 3 groups: 1. Sham-operated group, 2. HI group, and 3. MgSO(4)-treated HI group. The second and third groups underwent ischemia followed by exposure to hypoxia for 2 h (Vannucci model). The first and second groups received intraperitoneal saline and the third group received intraperitoneal MgSO(4). On PND 10, eyes of the pups were evaluated for RGC count, apoptotic index, VEGFR-2, and GFAP expressions. RESULTS: In both HI and MgSO(4)-treated HI group, the mean total RGC counts were found to be significantly decreased. However, the mean total RGC count in the MgSO(4)-treated HI group was significantly higher than that of the HI group. The mean apoptotic index was found to be significantly increased in the HI group. Retinal VEGFR-2 and GFAP expressions were found to be significantly higher in the HI group. CONCLUSIONS: Magnesium sulfate preconditioning andtreatment in preterm HI rat model might diminish apoptosis, relatively preserve RGCs, and reduce retinal VEGFR-2 and GFAP expressions.