壬基酚暴露对大鼠胃粘膜的氧化损伤作用

目的初步探讨壬基酚(Nonylphenol,NP)暴露对SD大鼠胃组织SOD、GSH-Px活性以及MDA含量的影响。方法将24只清洁级SD大鼠随机分为4组,每组6只。阴性对照组给予玉米油,剂量组分为低、中、高剂量组给予NP+玉米油灌胃染毒,NP浓度分别为25、50、100mg/kg,每天灌胃染毒1次,连续灌胃42d后麻醉处死取胃组织,通过HE染色观察胃组织的病理变化,利用化学比色法检测胃组织中超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活性及丙二醛(malondialdehyde,MDA)含量。结果胃粘膜肉眼观各组均未出现出血、坏死,NP中剂量组胃粘膜皱襞出现了针眼大小的色素沉着点,NP高剂量组明显增多;HE染色见正常组大鼠胃黏膜上皮细胞及黏膜腺体排列整齐、完整,未见脱落、缺损,黏膜肌层及间质未见异常;低剂量组上皮细胞和黏膜腺体充血水肿,有血管扩张;中、高剂量组胃黏膜上皮细胞破损、脱落,腺管肿胀、充血,可见黏膜及间质部有淋巴细胞浸润;与对照组比较,高剂量组SOD活性降低,差异有统计学意义(P<0.05),低、中剂量组与对照组比较差异无统计学意义(P>0.05),SOD活性随着染毒剂量的增加呈现逐渐下降的趋势;与对照组比较,各染毒组GSH-Px活性差异无统计学意义;与对照组比较,低剂量组MDA含量增高(P<0.05),中、高剂量组与对照组比较差异无统计学意义(P>0.05)。结论25 mg/kg壬基酚短期暴露对胃粘膜有一定氧化损伤作用。

Oxidative damage of gastric mucosa induced by nonylphenol exposure in rats

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 with 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,without any defect or abnormality in mucosal myometrium.In the low dose group,hyperemia and edema,and vasodilation in the mucosal glands were observed;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(P<0.05),while there was no significant difference between the low/medium dose groups and the control group(P>0.05).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 groups.Compared with the control group,the MDA content in the low dose group was increased significantly(P<0.05),while there was no significant difference in the middle and high dose groups.Conclusion Short-term exposure to 25 mg/kg nonylphenol can cause oxidative damage to gastric mucosa.