Oxidative damage of gastric mucosa induced by nonylphenol exposure in rats / 公共卫生与预防医学

ABSTRACT

Objective To investigate the effects of nonylphenol (NP) exposure on the activity of SOD and GSH-Px and the content of MDA in gastric tissue of SD rats. Methods Twenty-four clean SD rats were randomly divided into four groups, 6 in each group. The negative control group was given corn oil, and the exposure groups included low, medium and high doses of NP treatment groups. NP was prepared in corn oil and administrated intragastrically. The concentration of NP was 25, 50 and 100 mg/kg, respectively, given once a day. After 42 days of continuous intragastric administration, the animals were sacrificed under anesthesia and gastric tissues were collected. The pathological changes of gastric tissues were observed by HE staining. The activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and level of malondialdehyde (MDA) in gastric tissues were respectively detected by chemical colorimetry. Results No bleeding or necrosis was found in the gastric mucosa of all groups by naked eye view. Pinhole-sized pigmentation was found in the stomach wall fold and bulge of NP medium dose group, and the number of pigmentation spots was increased significantly in NP high dose group. HE staining showed that the epithelial cells and glands of gastric mucosa of rats in normal group were arranged neatly and intact, and no any defect or abnormality in mucosal myometrium was observed. In the low dose group, hyperemia and edema, and vasodilation in the mucosal glands were observed, while in the medium and high dose groups, the epithelial cells of the gastric mucosa were damaged and exfoliated, the glandular ducts were swollen and congested, and lymphocyte infiltration was observed in the mucosa and interstitium. Compared with the control group, SOD activity in the high dose group was significantly decreased (P0.05). SOD activity decreased gradually with the increase of the dose. Compared with the control group, there was no significant difference in GSH-Px content among the NP exposure groups. Compared with the control group, the MDA content in the low dose group was significantly increased (P<0.05), while there was no significant difference in the medium and high dose groups. Conclusion Short-term exposure to 25mg/kg nonylphenol caused oxidative damage to gastric mucosa.