Figure 5. Ground squirrel NCX2 expression in rat primary neurons increased the viability of neurons exposed to glutamate.

(A) Expression of ground squirrel NCX2 in rat primary neurons. Neurons transfected with ground squirrel NCX2 were labeled by EGFP, and neuronal survival was determined 6 hours after glutamate treatment. Scale bar, 25 µm. The results show that neurons transfected with ground squirrel NCX2 (EGFP positive cells identified by red arrows) are less susceptible to glutamate injury than were untransfected neurons (identified by white arrows). In addition, the effect of overexpressing NCX1, NCX2 and NCX3 from both rat and ground squirrel neurons were tested. The results are shown in the bar graph (B). The data suggest that the expression of ground squirrel NCX2 promotes survival under glutamate toxicity conditions, whereas overexpression of rat NCX1 enhances cell death. In contrast, overexpression of other rat and ground squirrel NCXs has no effect. n = 5 separate experiments, P<0.01.