Histology of gastric fundic mucosa in sham-, VSG- and RYGB- operated rats.

<p><b>Panel A.</b> Post-mortem representative macroscopic photomicrographs of stomach of sham-, VSG- or RYGB-operated rats. <i>(top)</i> normal stomach showing fundus (1) and antrum (2); <i>(middle)</i> residual stomach after VSG with fundus (1), antrum (2), duodenum (3) and, pylorus <i>(arrow)</i>; <i>(bottom)</i> excluded stomach in RYGB and gastric pouch (1) directly anastomosed to the jejunum (4). <b>Panel B:</b> representative Hematoxylin and Eosin staining (H&E) of fundic mucosa. Note the hyperplasia of mucous neck cells <i>(black arrow heads)</i> after VSG and RYGB. <b>Panel C:</b> fundic mucosa sections stained with periodic acid Schiff (PAS)/Alcian blue (AB). Mucous neck cells are PAS/AB positive <i>(black arrows)</i>. <b>Panel D:</b> immunostaining of Ki67-proliferating cells <i>(brown nuclei)</i> in formalin-fixed fundic mucosa section from sham <i>(top)</i>, remaining stomach after VSG <i>(middle)</i>, and GP after RYGB <i>(bottom)</i>.