Lectin binding sites in the stria vascularis of normal and endolymphatic hydrops-bearing guinea pigs.

为了阐明豚鼠血管纹边缘细胞的功能，进行了以下三个实验：1.用凝集素在Lowicryl K4M包埋材料的薄片上确定了特定的碳水化合物的定位。SBA、HPA和RCA-II标记(Gal-NAC和RCA-II)见于许多顶端小泡、内小体和顶管以及边缘细胞腔质膜的微绒毛和微吞饮细胞内陷。LFA标记(唾液酸)位于边缘细胞基底层的质膜上。WGA(Glu-NAC)沿构成血管纹的所有类型细胞的质膜分布。边缘细胞的内化膜、许多顶端小泡、内小体和顶端小管具有相同的碳水化合物成分，这一事实表明这些结构。可以关联在一起。A…对阳离子铁蛋白的摄取在电子显微镜下观察到血管纹边缘细胞内有更多的硬膜小泡。CFs颗粒呈簇状分布，散布在面向内淋巴的游离面质膜和边缘细胞的小窝中。在顶端小泡、包被小泡和内小体中也检测到它们。这些发现表明，顶端小泡与自由表面质膜有关，并与内淋巴和边缘细胞之间有效的离子交换有关。实验诱导一年后，用细胞化学方法观察内淋巴积水对血管纹Na-K-ATPase活性的影响。形态观察显示边缘细胞基底部皱缩，细胞间肿胀，中间细胞萎缩消失。尽管有这样的形态变化，但在积水标本的血管纹和对照标本之间，Na-K-ATPase活性的定位没有明显的差异。较少

In order to clarify the function of the marginal cells in the guinea pig stria vascularis, the following three experiments were performed :1. Lectins were employed to determine the localization of specific carbohydorates on thin sections of Lowicryl K4M embedded materials. SBA, HPA and RCA-II labeling (Gal-NAc and Gal) was observed in many apical vesicles, endosomes and apical tubules as well as on the microvilli and micropinocytotic invaginations of the luminal plasma membrane of the marginal cells. LFA labeling (sialic acid) was found on the plasma membrane of the basal infoldings of the marginal cells. WGA (Glu-NAc) was detected along the plasma membrane of all types of cells constituting the stria vascularis. The fact that the membranes of internalization, many of the apical vesicles, endosomes and apical tubules in the marginal cells possess the same carbohydrate moieties suggested that these structures. may be associated together.2. The uptake of cationized ferritin (CF) by the a … More pical vesicles in the marginal cells of the stria vascularis was electron microscopically studied. CF particles were found in clusters, scattered on the free surface plasma membrane facing the endolymph and in the caveolae of the marginal cells. They were also detected in the apical vesicles, coated vesicles and endosomes. These findings suggested that the apical vesicles are associated with the free surface plasma membrane, and that they are related to the efficient exchange of ions between the endolymph and the marginal cells.3. The effect of endolymphatic hydrops on the Na-K-ATPase activity in the stria vascularis was cytochemically investigated one year after experimental induction. The morphological observations revealed intercellular dropsy and shrinkage of the basal infoldings of the marginal cells, and shrinkage and disappearance of intermediate cells. In spite of such morphological alterations, no remarkable difference was found, as regards the localization of the Na-K-ATPase activity, between the striae vasculares of hydrops and control specimens. Less