Fig. 4.

Co-expression of Kir4.1 and Kir5.1 in optic nerve oligodendrocytes and astrocytes. Co-immunolocalization of Kir4.1 and Kir5.1 in optic nerve explant cultures, in astrocytes identified by GFAP immunolabelling (A) and oligodendrocytes identified by PLP-DsRED (B). The overlay and individual channels are illustrated, together with the co-localisation channel for Kir4.1/Kir5.1 (Aii, Bii). Boxed areas on overlay images (Ai, Bi) are enlarged in Avi–Aviii and Bvi–Bviii, to illustrate punctate colocalization of Kir4.1 and Kir5.1 along processes (some indicated by arrows). Scale bars 20 μm. Quantification of the number of voxels that were positive for Kir4.1 and Kir5.1 alone and of Kir4.1/Kir5.1 together, in astrocytes (C, n = 15) and oligodendrocytes (D, n = 13); data are mean ± SEM. Co-immunoprecipitation of Kir4.1 with Kir5.1 (E) and of Kir5.1 with Kir4.1 (F) from total brain and optic nerve (ON) lysates; negative controls were Kir4.1 knock-out mice (−/−) for Kir4.1, and using the blocking peptide for Kir5.1