Wagner C, Batiz L F, Rodríguez S, Jiménez A J, Páez P, Tomé M, Pérez-Fígares J M, Rodríguez E M
Instituto de Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.
J Neuropathol Exp Neurol. 2003 Oct;62(10):1019-40. doi: 10.1093/jnen/62.10.1019.
Two phases may be recognized in the development of congenital hydrocephalus in the hyh mutant mouse. During embryonic life the detachment of the ventral ependyma is followed by a moderate hydrocephalus. During the first postnatal week the cerebral aqueduct becomes obliterated and a severe hydrocephalus develops. The aim of the present investigation was to elucidate the cellular phenomena occurring at the site of aqueduct obliteration and the probable participation of the subcommissural organ in this process. Electron microscopy, immunocytochemistry, and lectin histochemistry were used to investigate the aqueduct of normal and hydrocephalic hyh mice from embryonic day 14 (E-14) to postnatal day 7 (PN-7). In the normal hyh mouse, the aqueduct is an irregularly shaped cavity with 3 distinct regions (rostral, middle, and caudal) lined by various types of ependyma. In the hydrocephalic mouse, these 3 regions behave differently; the rostral end becomes stenosed, the middle third dilates, and the caudal end obliterates. The findings indicate that the following sequence of events lead to hydrocephalus: 1) denudation of the ventral ependyma (embryonic life); 2) denudation of dorsal ependyma and failure of the subcommissural organ to form Reissner fiber (first postnatal week); 3) obliteration of distal end of aqueduct; and 4) severe hydrocephalus. No evidence was obtained that NCAM is involved in the detachment of ependymal cells. The process of ependymal denudation would involve alterations of the surface sialoglycoproteins of the ependymal cells and the interaction of the latter with macrophages.
在hyh突变小鼠先天性脑积水的发展过程中可识别出两个阶段。在胚胎期，腹侧室管膜脱离后会出现中度脑积水。在出生后的第一周，中脑导水管闭塞，严重脑积水形成。本研究的目的是阐明中脑导水管闭塞部位发生的细胞现象以及联合下器官在此过程中可能的参与情况。采用电子显微镜、免疫细胞化学和凝集素组织化学方法，对正常和脑积水的hyh小鼠从胚胎第14天（E-14）到出生后第7天（PN-7）的中脑导水管进行研究。在正常的hyh小鼠中，中脑导水管是一个形状不规则的腔，有3个不同区域（头端、中间和尾端），由不同类型的室管膜衬里。在脑积水小鼠中，这3个区域表现不同；头端变窄，中间三分之一扩张，尾端闭塞。研究结果表明，以下一系列事件导致脑积水：1）腹侧室管膜剥脱（胚胎期）；2）背侧室管膜剥脱和联合下器官未能形成赖氏纤维（出生后第一周）；3）中脑导水管远端闭塞；4）严重脑积水。未获得NCAM参与室管膜细胞脱离的证据。室管膜剥脱过程将涉及室管膜细胞表面唾液糖蛋白的改变以及后者与巨噬细胞的相互作用。
