Microphotographs showing von Willebrand factor, MECA 32 and vimentin immunoreactivities in coronal sections of the tuberal region of the hypothalamus. A: Low magnification photomontage of von Willebrand factor (green) and MECA 32 (blue) immunoreactivities. B: Low-magnification photomontage of the same section showing vimentin immunoreactivity (red) merged with A. As shown in B, vimentin is an intermediary filament protein of the cytoskeleton that is expressed in both brain vessels and cells lining the third ventricle, including tanycytes (characterized by their elongated body and long basal process) and “typical” ependymal cells (cuboidal cells without processes located in the dorsal part of the third ventricle). C: High magnification image showing the vimentin-labeled processes of dorsal tanycytes (red, empty arrows) contacting von Willebrand factor-positive brain vessels (green, arrow). D: High magnification image showing the vimentin-labeled processes of median eminence tanycytes (red, empty arrows) contacting MECA 32-positive pituitary portal vessels (blue, asterisk). 3V, third ventricle; ME, median eminence. Scale bar = 100μm in B; 20μm in C and D.