性激素对小鼠第三脑室壁表面微细结构的影响——扫描电镜观察

INFLUENCES OF SEX HORMONES ON THE SURFACE FINE STRUCTURES OF THE THIRD VENTRICLE WALL IN NMRI-MICE——A SCANNING ELECTRON MICROSCOPICAL INVESTIGATION

应用扫描电镜观察了NMRI小鼠第三脑室壁表面的微细结构和性激素对这些结构的影响。第三脑室壁可分为满布纤毛的背外侧部和以微绒毛为主的腹底部以及两者之间的过渡区。正中隆起区的室管膜表面缺乏纤毛和微绒毛,但有许多泡状结构,雌激素可使其明显增大,摘除卵巢则使之变小并与雄性者相似。泡状结构破裂后,向室腔排出微粒状物质,雌激素有促进此种微粒排出的作用。促垂体区的室管膜细胞具有较长的微绒毛,摘除卵巢可使其数目减少,给以雌激素则使其明显增多。微绒毛减少是细胞体积增大的结果,表明摘除卵巢可加强室管膜细胞的吸收功能。在乳头体前区,于微绒毛之间常有散在的小气球状结构,雌激素可使它们明显增大,数目增多,其机能意义不明。还见到一些室管膜上细胞的波浪状胞膜在细胞的一侧伸展很长,表明至少有一部分室管膜上细胞具有吞噬细胞功能,有迹象表明此种细胞穿过室管膜而进入脑室。

By using the scanning electron microscopical method,the influences of sex hormones on the surface fine structures of the third ventricle wall in female mice were investigated.Ovariectomy made the microvilli of the ependymal cell of the hypophysiotrophic area become obviously less in number and thinner in size like those of male mice when cbmpared with that of estradiol administration group.Injection of estrogen resulted in an increase in number and size of the microvilli.In the dorsal surface of median eminence,injection of estrogen made the bleb-like structures on the lumen surface of this area enlarge.The luminal surface of some blebs broke down and numerous small granules were secreted from inside to the ventricle lumen.The characteristic feature of the premammillary area was the presence of numerous balloon-like structures.Injecting estradiol to the gonadectomized female mice resulted in an increase of the balloon-like structure both in number and size.The content of the balloonlike structure was a mass of granule-like substance enveloped by membrane.Sometimes the granules appeared to be secreted into the ventricle lumen through an opening of the membrahe.In the dorsal partof lateral wall of third ventricle,within the cilia meadow there were some ciliafree"isles",on which a lot of debris distributed.Some isles had intimate relation to the supraependymal cells(SEC).Taking the intensifying of ramification and membrane folding of SEC as the criteria of activity,SEC seemed most active in the estrogen treatment group.There were evidence tending to indicate that SEC migrated from the subependymal layer or ependymal layer into the ventricle lumen.