A new morphological aspect of the brush cells of the mouse gallbladder epithelium.

The brush cells of the gallbladder epithelium of the mouse have microvilli not only at their luminal border but also on their lateral surface, from the level of the nucleus to the junctional complex. The lateral microvilli radiate from the brush cell in all directions, contain a core of filaments, and penetrate up to 3 mum into the adjacent cells. The microvilli in these locations display small desmosomes at their base.