Figure 4.

OPA1 mutation triggers activation of NMDA receptors in Opa1^enu/+ mice. (a) Opa1^enu/+ mice significantly increased NR1, NR2A, and NR2B protein expression compared with wild-type control mice. Values are mean±S.D. (n=4 retinas/group). ^*Significant at P<0.05 compared with wild-type control mice. (b–d) NR1 immunohistochemistry. When the primary antibody for NR1 was omitted, there was no binding of the secondary antibody (b). Compared with wild-type control mouse (c), Opa1^enu/+ mouse showed increased NR1 immunoreactivity in the IPL and GCL (arrowheads, d). (e–g) NR2A immunohistochemistry. When the primary antibody for NR2A was omitted, there was no binding of the secondary antibody (e). Compared with wild-type control mouse (f), Opa1^enu/+ mouse showed increased NR2A immunoreactivity in the GCL (arrowheads, g). ONL, outer nuclear layer; OPL, outer nuclear layer; INL, inner nuclear layer; GCL, ganglion cell layer; NR, NMDA receptor. Scale bar, 20 μm (b–g)