Figure 1.

(A) Immunoblot of membrane fractions from spinal cord, cerebellum, and cerebral cortex (plus hippocampus). The blot was probed with affinity-purified anti-AQP4 and shows 29- and 31-kDa bands (splice variants) and a higher molecular mass band (undissociated-AQP4 oligomers). (B) Thin cryosection (0.9 μm) of spinal cord. Extensive AQP4-immunolabeling is observed on glial processes adjacent to capillaries (arrows) and adjacent to neurons (arrowhead). (×670.) (C) Ultrathin Lowicryl section of cerebellum. AQP4-labeling is associated with the glial process (G) on the side directly facing the capillary endothelium (E). (×72,000.)