Figure 4

Transmission electron micrograph of an intestinal villus (ileum) from a silver nanoparticle exposed rat. Transmission electron micrographs of ultra-thin sections (stained with uranyl acetate and lead citrate) showing a) overview of an intestinal villus (LU = lumen) highlighting two regions of interest (I and II) in the lamina propria (LP) as well as in a region between lamina propria and the epithelium (E), respectively; b-c) details of region I showing granules in a lysosome (Ly) within a macrophage (M); d-f) details of region II showing granules in close proximity to a capillary (C) within the lamina propria and in the basal lamina (BL) of the epithelium. The region of interest highlighted in d) is presented in e), whereas f) is showing the basal lamina in more detail.