长爪沙鼠作为牛带绦虫终末宿主实验动物的初步研究

Preliminary study on Mongolian gerbil as an animal model for experimental infection of Taenia saginata

目的利用长爪沙鼠作为牛带绦虫终末宿主实验动物模型的探索。方法将牛带绦虫虫卵用酶法孵化后经皮下注射感染免疫抑制小鼠,不同时期获取的活囊尾蚴分别经灌胃感染沙鼠,同时皮下注射地塞米松1～2mg/d进行免疫抑制。感染后1～62d剖杀沙鼠,观察沙鼠的感染情况,从小肠检获的虫体经整体染色或作常规切片HE染色,观察其外部形态及内部结构。结果8只沙鼠被感染,分别在感染后1,2,3,10,30d从沙鼠小肠内检获4,4,4,6,1条虫体,其中11条完整虫体的长度为10.56(1.0～45.5)mm。感染后10,30d虫体分节,但节片较幼稚,未见原始生殖细胞和发育成熟的生殖器官。结论小鼠体内获取的囊尾蚴可以在免疫抑制的长爪沙鼠小肠内生长发育一段时间,但未发育成熟。

Attempts were carried out to establish experimental definitive host model for Taenia saginata in Mongolian gerbil. Every mouse was treated with dexamethasone （0. 5mg/d） one month through subcutaneous injection. Immunosuppressire mice were infected with oncospheres of Taenia saginata by subcutaneous injection. All the mice were still treated with dex- amethasone one month after infection. Taenia saginata cysticerci were collected from the mice on 176th,209th,243tho 280th, 298th day postinfection. The fresh cysticerci were incubated in physiological saline with 10% pig bile. Mongolian gerbils（from 23-day-old to 40-day-old）were infected with viable cysticerci after incubation via oral inoculation, every gerbil was treated with dexamethasone （1-2mg/d）. The gerbils were sacrificed were obtained , immersed in physiological saline ,and cut between 1 and 62 days postinfection. Small intestines of the gerbils open longitudinally with fine scissors. The worms from small intestines of the infected gerbils were examined , measured ,then fixed in 70% alcohol or Zenker＇s solution. The morphological char- acteristic of the worms were observed. The worms were found in 8 gerbils（from 27-day-old to 31-day-old）. The number of worms recovered from the gerbils were 4th, 4th, 4th, 6 and 1 on lth, 2th, 3th, 10th and 30th day postinfection, respectively. The mean length of 11 whole worms were 10. 56 （1.0-45.5） mm. Four suckers were found on the worms. The worms had several segments on 10th, 30th day postinfection. Genital primordia and sexually mature organ were not observed in these segments. It concluded that the cysticerci from immunosuppressive mice could develop to a certain extent in immunosuppressive Mongolian gerbils, none grew to the mature stage.