Antonakopoulos G N, Turton J, Whitfield P, Newman J
Department of Histology, University of Crete Medical School, Greece.
Int J Parasitol. 1991 Apr;21(2):187-93. doi: 10.1016/0020-7519(91)90009-v.
The urinary bladders of rats infected with Trichosomoides crassicauda were studied by light, scanning and transmission electron microscopy. The bladder epithelium of infected rats showed a diffuse, mild, flat hyperplasia, four to six cells thick. The anterior parts of adult female worms were embedded in tunnels within the hyperplastic epithelium with the posterior portions of the parasites lying free in the bladder lumen. The hyperplastic epithelial cells forming the inner layer of the tunnel wall, adjacent to the parasite, showed degenerative changes. These cells contained single or multiple pycnotic nuclei. Their cytoplasm was fibro-granular in appearance, with few distinct organelles, and the luminal surfaces of the cells were not limited by plasma membranes. Small numbers of granular cells, similar in appearance to mast cells, were seen in, and possibly crossing, the epithelium. There was no infection-related increase in the number or type of inflammatory cells in the lamina propria. Questions of interest emerging from this study relate to the nutrition of an adult nematode occupying an intra-epithelial location, and the absence of a significant chronic inflammatory response to the mature worm. It is suggested that the avascular hyperplastic epithelium of the bladder is an immunologically 'protected site' for the mature female T. crassicauda.
利用光学显微镜、扫描电子显微镜和透射电子显微镜对感染粗尾毛滴虫的大鼠膀胱进行了研究。感染大鼠的膀胱上皮呈现弥漫性、轻度扁平增生，厚四到六层细胞。成年雌虫的前部嵌入增生上皮内的隧道中，虫体后部游离于膀胱腔内。形成隧道壁内层、与寄生虫相邻的增生上皮细胞呈现退行性变化。这些细胞含有单个或多个固缩核。其细胞质呈纤维颗粒状，几乎没有明显的细胞器，细胞的腔面不受质膜限制。在膀胱上皮内可见少量外观类似于肥大细胞的颗粒细胞，且这些细胞可能穿过上皮。固有层中炎症细胞的数量或类型并未因感染而增加。该研究中出现的有趣问题涉及占据上皮内位置的成年线虫的营养问题，以及对成熟虫体缺乏显著的慢性炎症反应。有人提出，膀胱的无血管增生上皮是成熟雌性粗尾毛滴虫的免疫“保护位点”。
