蓝氏贾第鞭毛虫滋养体有丝分裂的初步观察

目的观察体外培养的蓝氏贾第鞭毛虫滋养体有丝分裂。方法用改良的TYI-S-33培养基培养贾第虫。从培养第6h开始,每间隔2h取分裂的细胞直至第24h,制备涂片,Giemsa染液染色,用光镜和透射电镜观察细胞分裂状况。结果有丝分裂前期:染色质凝集形成细长的染色质丝;中期:形成大小约1μm的棒状染色体,且全部排列在细胞核中央,或分散在核内;后期:姐妹染色单体分开,向细胞核两极移动,核膜拉长;末期:核膜中间向内缢束呈葫芦状,细胞核缢裂成两个子核,随即进行胞质分裂。结论蓝氏贾第鞭毛虫滋养体有丝分裂与典型真核细胞相似,但分裂期核膜始终存在,为半开放式分裂。

Preliminary observation on the mitosis of Giardia lamblia trophozoites

To observe the mitosis of Giardia lamblia （G. lamblia） trophozoites in vitro, the trophozoites were cultured in modified TYI-S-33 medium at 37℃. Smears were made with cells collected at a two-hour interval from 6h to 24h and then stained by Giemsa staining technique. The smears were observed with both light microscopy and electron microscopy. This study reflected that there were four stages in the mitosis process： In prophase, the chromatins condensed into chromatin threads. In metaphase, the chromosomes formed short rods with 1μm in length and all of them were concentrated in the center of the nucleus. In anaphase, the sister chromatids separated from each other and the nuclear membrane stretched. In telophase, the midline of the cell envelope contracted to the inner side to make the cell become gourd shape and the nucleus split into two sister-nuclear then the cytoplasm divided. Results indicated that the formation of mitosis in G. lamblia was similar to that of typical division in eukaryotic cell. But the nuclear membrane was still intact during the period of the mitosis process, which suggested that the mitosis observed in G. lamblia was a semi-open type.