卡氏肺孢子虫发育增殖过程的超微结构研究

Ultra-structural Study on the Process of Development and Reproduction of Pneumocystis Carinii

目的 :研究卡氏肺孢子虫发育增殖过程的超微结构。方法 :用地塞米松诱导大鼠卡氏肺孢子虫肺炎 ,取肺组织制成透射电镜标本 ,观察肺内虫体的超微结构和发育增殖过程。结果 :肺内卡氏肺孢子虫有滋养体、囊前期和包囊三个发育阶段。滋养体的生殖方式有二分裂、外出芽、内出芽及接合生殖 ,并见到囊前期和包囊内的囊内小体的分裂增殖过程。此外 ,虫体内有丰富的线粒体 ,且随虫体的发育和分裂 ,线粒体的数量、大小和形状也发生明显的变化。严重感染时虫体以滋养体为主。结论 :卡氏肺孢子虫的生活史由滋养体、囊前期和包囊三个发育阶段构成 。

Objective: To study the ultra-structure of Pneumocystis carinii(PC) on the process of development and reproduction in lung tissue. Methods: PC pneumonia of Wistar rats using dexamethasone were induced. Then the lung tissues of the rats to observe the ultra-structure of PC on the process of development and reproduction with transmission electron microscopy were made. Results: In the lungs, there are three developmental stages of PC, that is trophozoites, precysts and cysts. The reproductive forms of trophozoites include the binary fission, endogenous budding, exogenous budding and conjugation. We also observed the fissive process of the precysts and tiny body within cysts. The mitochondria are rich and variable in size, shape and number with the development and division of PC. More trophozoites are in the alveolar cavity as severe infection. Conclusion: The life cycle of Pneumocystis carinii is composed of three developmental stages, namely, trophozoite, precyst and cyst, and its types of reproduction includes asexual and sexual reproductions.