2.6. Histology and Morphometric Analysis of the Intestine

Intestinal villus height (VH) and crypt depth (CD) were measured in accordance with our previously reported method [23]. Fixed intestinal samples were dehydrated, embedded in paraffin wax, cut into serial 5 μm sections, and stained by hematoxylin and eosin. Histological sections were observed by a Nikon phase contrast microscope (Nikon Eclipse 80i, Nikon Co., Tokyo, Japan) at 40× magnification coupled with an integrated digital imaging analysis system. Five vertically crosscutting sections were selected for each sample. The vertical distances from the villous tip to villous–crypt junction level and from the villous–crypt junction to the lower limit of the crypt were taken as VH and CD, respectively. Ten well-orientated villi and their associated crypt per section were measured using an image analyzer (Lucia Software, Lucia, Za Drahou, Czechoslovakia). The mean value of 50 measurements per sample was submitted for statistical analysis.