Figure 1: Sodium channel Nav1.5 expression in astrocytes within control tissue and active multiple sclerosis lesions. GFAP positive astrocyte (green) within control tissue does not exhibit Nav1.5 labelling. In contrast, GFAP positive astrocyte within an active multiple sclerosis lesion displays robust Nav1.5 labelling (red). Merged image of GFAP and Nav1.5 is yellow. GFAP is a biomarker for the visualization of reactive astrocytes (Courtesy Dr. Joel A. Black, Yale University).