Involvement of mGluR I in EphB/ephrinB reverse signaling activation induced retinal ganglion cell apoptosis in a rat chronic hypertension model.

Involvement of mGluR I in EphB/ephrinB reverse signaling activation induced retinal ganglion cell apoptosis in a rat chronic hypertension model. Brain Res. 2018 Jan 20;: Authors: Zhao Y, Li Q, Li XY, Cui P, Gao F, Zhu K, Li LZ, Sun XH, Wang Z Abstract EphB/ephrinB reverse signaling is involved in retinal ganglion cell (RGC) apoptosis in experimental glaucoma. Here, we further investigated the mechanisms underlying EphB/ephrinB reverse signaling activation induced RGC apoptosis in a rat chronic ocular hypertension (COH) model, using patch-clamp techniques in retinal slices. In COH retinas, RGCs showed higher spontaneous firing frequency and much more depolarized membrane potential as compared to control, which was mimicked by intravitreally injection of EphB2-Fc, an activator of ephrinB2. The changes in RGC spontaneous firing and membrane potential could be reversed by the tyrosine kinase inhibitor PP2, suggesting that EphB/ephrinB reverse signaling activation induced RGC hyperexcitability. Intravitreal pre-injection of either LY367385 or MPEP, selective mGluR1 and mGluR5 antagonists, also blocked the changes in RGC spontaneous firing and membrane potential. Co-immunoprecipitation experiments showed an interaction between ephrinB2 and group I metabotropic glutamate receptor (mGluR I) (mGluR1/mGluR5). Furthermore, intravitreal pre-injection of the mixture of L-NAME (an NO synthase inhibitor) and XPro1595 (a selective inhibitor of solub...
Source: Brain Research - Category: Neurology Authors: Tags: Brain Res Source Type: research