Fig. 6.

Stereoscopic images of astrocyte gap junctions in the suprachiasmatic nucleus after labeling for Cx43 and AQP4 (A), in the supraoptic nucleus after labeling for Cx30 (B), in the supraoptic nucleus after double labeling for Cx43 and Cx30 (C), and in the paraventricular nucleus after triple labeling for Cx30, Cx32, and Cx43 (D). A, Two astrocyte-to-astrocyte gap junctions labeled for Cx43 (20 nm beads;large arrows) beneath their E-faces (E) and P-faces (P). Square arrays in P-faces were labeled for AQP4 (10 nm gold beads; small arrow and inset). B, Astrocyte-to-astrocyte gap junction labeled for Cx30 (10 nm gold).C, A gap junction linking two astrocyte processes after double labeling for Cx30 (10 nm gold beads) and Cx43 (20 nm gold beads). Astrocytes were positively identified by the presence of AQP4 square arrays in both P-faces (white arrows) and E-faces (black arrows), as well as by the high density of IMPs on both P- and E-faces. D, Two astrocyte gap junctions triple-labeled for Cx30 (20 nm gold), Cx43 (30–40 nm gold), and Cx32 (10 nm gold; none present). Cx32 was not detected in astrocyte-to-astrocyte gap junctions but was detected in astrocyte-to-oligodendrocyte gap junctions (Fig. 5).