Like in most Crustacea, the cuticle of terrestrial isopods is hardened by a calcareous mineral phase. This rigid cuticle is frequently shed during a process called moulting. To reduce calcium loss, Porcellio scaber eats the shed cuticle, the exuviae, and absorb the calcium from it through large tubular diverticula of the intestine, called the mid gut glands or hepatopancreas. After moulting the absorbed calcium should be transported immediately into the hemolymph from which it is used to rapidly mineralize the new cuticle. This suggests that the hepatopancreas epithelium transports calcium from the lumen to the hemolymph. We used TEM, energy-filtered TEM and electron-probe X-ray microanalysis to analyse the distribution of elevated calcium within the hepatopancreas cells of P. scaber. We used animals in the postmoult stage that have eaten their exuviae and, as a control, those that have not ingested the exuviae. To minimize calcium loss within the samples, we used high pressure frozen and freeze substituted samples and propane-1–3-diol as floatation medium for thin-sectioning. The results reveal intracellular dense deposits containing calcium, phosphorus and oxygen at the apical microvillus membrane, within the cytoplasm, attached to vesicles and to the basolateral membrane, as well as extracellular between cells and the basal lamina. Control animals were devoid of these deposits. The results indicate that calcium from the exuviae is absorbed and transported across the epithelium into the hemolymph. We propose that during transport, intracellular calcium is bound to phosphate avoiding toxic effects of high concentrations of ionized calcium.

与大多数甲壳类动物一样，陆生等足类动物的角质层被钙质矿物相硬化。这种坚硬的角质层经常在称为换羽的过程中脱落。为了减少钙流失，Porcellio scaber吃掉脱落的角质层，蜕皮，并通过肠道的大管状憩室（称为中肠腺或肝胰腺）从中吸收钙。蜕皮后吸收的钙应立即输送到血淋巴中，用于快速矿化新的角质层。这表明肝胰腺上皮将钙从管腔运输到血淋巴。我们使用 TEM、能量过滤 TEM 和电子探针 X 射线微量分析来分析P. scaber肝胰腺细胞内升高的钙的分布. 我们使用已经吃掉蜕皮的蜕皮后阶段的动物，以及那些没有摄取蜕皮的动物作为对照。为了最大限度地减少样品中的钙损失，我们使用高压冷冻和冷冻替代样品和丙烷-1-3-二醇作为薄切片的漂浮介质。结果显示，在顶端微绒毛膜、细胞质内、附着于囊泡和基底外侧膜以及细胞和基底层之间的细胞外，含有钙、磷和氧的细胞内致密沉积物。对照动物没有这些沉积物。结果表明，来自蜕皮的钙被吸收并通过上皮运输到血淋巴中。我们建议在运输过程中，