Effects of sesamol on morphological and histological changes in water immersion restraint- (WIR-) treated rats. Rats were divided into three groups: Group I, non-WIR (normal) group ((a), (d)); Group II, WIR (control) group rats were subjected to WIR ((b), (e)); and Group III, sesamol-plus-WIR group rats were orally given sesamol (1 mg/kg) 30 min before WIR ((c), (f)). Morphological ((a)–(c)) and histological ((d), (e)) changes were assessed after WIR. Non-WIR ((a), (d)) and WIR-plus-sesamol (c, f) groups appeared normal in both morphological and histological examinations. WIR group showed a large hemorrhagic ulcerated area (b) and a loss of the histological structure and a deep alteration of glandular epithelium serious lesions on mucosa (e) (hematoxylin-eosin, original magnification ×100). Arrow indicates disruption of surface epithelial cells of mucosa.