The pars distalis is highly vascular. The cells are arranged in cords, or clusters, which are surrounded by large fenestrated capillaries (clear areas, some of which contain RBCs) and a small amount of reticular (blue) connective tissue (HA7). Because of this organization of cells and vasculature, most cells lie directly adjacent to a capillary. As you look at HA7 more carefully, you can distinguish three classes of cells based on subtle differences in staining. The cytoplasm of the acidophils (A) stain orange or brick red, the basophil (B) cytoplasm stains reddish blue and the chromophobe (C) cytoplasm stains very poorly.