田鼠巴贝虫(Babesia mocroti)的超微结构观察

目的 观察田鼠巴贝虫的超微结构,了解田鼠巴贝虫在宿主红细胞中发育的形态变化。方法 运用扫描电镜观察田鼠巴贝虫侵入宿主红细胞的过程,运用透射电镜观察田鼠巴贝虫发育的形态变化过程及宿主红细胞形态变化情况。结果 扫描电镜下观察到田鼠巴贝虫裂殖子大小在406~981nm之间,虫体发育过程分为裂殖子、分裂中的裂殖子、滋养体3个阶段,裂殖子是通过红细胞膜上微孔进入宿主红细胞,分裂中的裂殖子可使红细胞变形,滋养体是通过溶解红细胞膜游离红细胞。透射电镜观察到田鼠巴贝虫裂殖子的核膜为双层膜结构,虫体中有核糖体、微管、内质网、线粒体和溶酶体等完整的细胞器,分裂中的裂殖子在侵入后期可见食物空泡,滋养体的外膜和核不规则,胞浆中含有颗粒和空泡,宿主红细胞的电子密度随着虫体的发育而逐渐变稀疏。结论 田鼠巴贝虫是含有完整细胞器的单细胞有机体,具有一般细胞所有的基本结构,它能完成多细胞动物所具有的生命机能,并以宿主红细胞中的血红蛋白作为生存氧料。

Ultramicrostructure observation of Babesia mocroti

The aim of this study is to observe the ultramicrostructure of Babesia mocroti and comprehend the morpholog- ic change of B. rnocroti developing in host＇s red cell. Scanning electron microscope （SEM） was used to observe the process that B. rnocroti invaded into the host＇s red cell; transmission electron microscope （TEM） was applied to view the morphologic change of B. rnocroti development as well as the morphologic alternation of host＇s red cell. The size of B. rnocroti merozoite was 406 981 nm with the observation by SEM. There were three stages in development process--dividing into merozoite, divid- ing merozoite, and trophozoite. Merozoite entered into host＇s red cell through micropore on erythrocyte membrane; dividing merozoite could split the red blood cell deformability; trophozoite was able to dissociate red cell by dissolving erythrocyte mere brane. When it comes to the observation by TEM, the nuclear membrane structure of merozoite was bilayer, with intact organ elles such as ribosomes, microtubules, endoplasmic reticulum, mitochondria and lysosomes etc. inside. Food vacuoles could be found at late stage of invasion in dividing merozoite. The outer membrane and nuclear of trophozoite were irregular. Granules and vacuoles contained in kytoplasm. The electron density of the host erythrocyte was gradually thinning with the development of B. mocroti. It＇s indicated that B. rnocroti is single-celled organisms which contains intact organelles and with general basic structure as common cell. This protozoa has the capability of life functions as multi-cellular animal and the host erythrocyte he- moglobin as the survival of oxygen feed.