大鼠长期摄入贫铀后的病理形态学特点观察

Pathological changes of rats after chronic ingestion of depleted uranium (DU)

目的观察大鼠长期食入不同剂量的贫铀后,亲代(F0)和子代(F1)大鼠各组织器官的病理形态改变。方法给F0和F1 Wistar大鼠共64只喂食贫铀饲料,分为F0代低、中、高剂量组和F1代中、高剂量组,另取10只大鼠做对照。给低、中、高剂量组大鼠喂食的贫铀含量分别为0.4mg/(kg·d)、4mg/(kg·d)和40mg/(kg·d)。F0代大鼠分别于7、14和20个月后处死,F1代大鼠分别于5、10和15个月后处死,分别取睾丸(卵巢)、脾脏、肾脏、肝脏、骨髓等脏器进行病理形态学观察。结果F0代的中、高剂量组大鼠摄入贫铀14个月后可见雄性的精曲小管萎缩,管壁增厚呈空虚网状,生精细胞层次减少,间质细胞增生,但仍见有精子生成;高剂量组可见到精子呈异型性改变,细胞核浓缩深染,且随着摄入时间延长改变愈趋明显;F1代大鼠摄入贫铀5个月后就有上述改变且更为严重。F0代中、高剂量组大鼠摄入贫铀14个月后肾小球轻度萎缩,间质增生明显,20个月时肾小球萎缩纤维化;F1代大鼠摄入贫铀5个月后就有上述改变。F0代中、高剂量组摄入贫铀7个月时脾脏生发中心和淋巴鞘增生,淋巴母细胞增生活跃,20个月时脾小体减少,生发中心稀疏;F1代大鼠摄入贫铀早期和晚期有类似改变。F0和F1代高剂量组摄入贫铀早期肝脏有炎症细胞浸润,晚期骨髓有核细胞减少,脂肪细胞增加。其余脏器未见明显的病理形态学改变。结论长期摄入贫铀对大鼠组织脏器的损伤具有一定的时间性和组织特异性,主要损伤集中在雄性生殖系统、免疫系统和造血系统,而对其他组织的损伤不明显。

Objective To observe the pathological changes of maternal and filial rats after chronic ingestion of depleted uranium （DU）in food. Methods Seventy four Wistar rats exposed to DU in food at doses of 0. 4, 4 and 40mg/（kg · d） for 15 to 20 months were divided as small dose group, medium dose group and high dose group. Animals of maternal generation （F0） were killed in 7, 14 and 20 months, of filial generation （F1） were killed in 5, 10 and 15 months. The pathological changes were then observed of testis （ovary）, spleen, heart, lung, kidney, liver, bone marrow and other organs. Results In the medium and high dose F0 groups, it was observed that the atrophy and incrassation of seminiferous tubule, decrease of spermatogenesis, hyperplasia of interstitial tissue, especially in high dose groups spermatozoon abnormality and nucleolus concentration in the rats testis after DU ingestion for 14 months. The changes became more severe with the prolongation of DU ingestion. Such changes occurred in filial rats （F1） after DC ingestion for 5 months. In the medium and high dose F0 groups, it was observed that a little atrophy of kidney glomerulus, hyperplasia of interstitial tissue after DC ingestion for 14 months, and kidney glomerulus fibrosis happened after DC ingestion for 20 months, such changes occurred in filial rats （F1） after DC ingestion for 5 months. In the medium and high dose F0 groups, splenic germinal center and periarterial lymphatic sheaths were hyperplasia, companies with lympbopoiesis after DC ingestion for 7 months, splenic white pulp became more small and sparse after DC ingestion for 20 months. The inflammatory cells infiltrated liver, hematopoietic cells of bone marrow decreased, while fat cells increased. Conclusion When Wistar rats are exposed to DU in food for a long time, the damage happened mainly in male reproductive system, immune system and hempatopietic system, and the pathological changes in other tissues and organs are not quite evident.