Ultrastructural evidence for transepithelial calcium transport in the anterior sternal epithelium of the terrestrial isopod Porcellio scaber (Crustacea) during the formation and resorption of CaCO3 deposits
Ultrastructural evidence for transepithelial calcium transport in the anterior sternal epithelium of the terrestrial isopod Porcellio scaber (Crustacea) during the formation and resorption of CaCO3 deposits
复制标题
陆生等足动物 Porcellio scaber（甲壳纲动物）胸骨前上皮在 CaCO3 沉积物形成和吸收过程中跨上皮钙转运的超微结构证据
DOI：
10.1007/s004410050606
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发表时间：
1996
影响因子：
3.6
通讯作者：
A. Ziegler
中科院分区：
文献类型：
--
作者：
A. Ziegler
摘要。在蜕皮之前，陆生等足类动物在前四个胸骨的上皮和旧角质层之间储存了大量的碳酸钙。为了检验胸骨前上皮是否具有指示上皮离子转运的特异性结构分化，我们使用电子显微镜技术研究了胸骨前上皮和作为对照的胸骨后上皮。在碳酸钙沉积形成过程中，胸骨前上皮的基底外侧质膜形成了一个复杂的相互连接的间质扩张和通道网络。在碳酸钙沉积物的吸收过程中，基底外侧的细胞间网络中出现了许多亲锇颗粒。亲锇颗粒的电子能量损失谱表明它们含有钙。在吸收碳酸钙沉积的过程中，胸骨前上皮的顶端质膜有许多表皮下褶皱。胸骨后上皮不存在间质网络、嗜锇颗粒和顶端、表皮下皱褶。综上所述，这些结构特征表明了经上皮离子运输，并且可能是胸骨前碳酸钙沉积形成和吸收所必需的。
Abstract.Before the molt, terrestrial isopods store large amounts of calcium carbonate between the epithelium and the old cuticle of the first four anterior sternites. In order to test whether the anterior sternal epithelium has specific structural differentiations indicative of transepithelial ion transport, the anterior sternal epithelium and, as a control, the posterior sternal epithelium were studied using electron-microscopical techniques. During the formation of calcium carbonate deposits, the basolateral plasma membrane of the anterior sternal epithelium forms an elaborate interconnected network of interstitial dilations and channels. Numerous osmiophilic granules occur within this basolateral intercellular network during resorption of the calcium carbonate deposits. Electron energy-loss spectroscopy of the osmiophilic granules indicates that they contain calcium. During the resorption of the calcium carbonate deposits, the apical plasma membrane of the anterior sternal epithelium has many subcuticular folds. An interstitial network, osmiophilic granules, and apical, subcuticular folds do not occur in the posterior sternal epithelium. Taken together, these structural features are indicative of transepithelial ion transport and are probably necessary for the formation and resorption of the anterior sternal calcium carbonate deposits.