Observations on Nutrition and Ultrastructure of Digestive Tract and Fat Body of the Giant Paranthurid Accalathura gigantissima Kussakin
Observations on Nutrition and Ultrastructure of Digestive Tract and Fat Body of the Giant Paranthurid Accalathura gigantissima Kussakin
复制标题
巨型金刚鹦鹉消化道和脂肪体营养及超微结构的观察
DOI：
--
复制
发表时间：
--
期刊：
影响因子：
--
通讯作者：
J. Wigele
中科院分区：
文献类型：
--
作者：
J. Wigele
南极洲的巨型仿甲纲动物Accalathura acutissima Kussakin（甲壳纲，等足目）适应于捕食端足类动物，端足类动物通过专门的口器刺穿并吸出。食管和胃首先将食物泵入高度可消化的后肠，随后食糜被运送到消化腺，由此较大的颗粒被胃的过滤器保留在肠中。后肠的超微结构显示了运输上皮的特征，没有发现消化酶分泌、细胞内消化或储存脂质或糖原的迹象。消化腺有非常活跃的细胞，负责吸收和分泌、细胞内消化和储存脂质（可能是甘油三酯）。脂质的代谢和运输没有SER的存在，它被RER取代。脂肪组织存在于肌肉之间，并在侧面和腹侧形成皮下脂肪体，在女性标本中可能相当庞大。所研究的未成熟雌性的脂肪细胞中除了脂质和糖原外，还含有大量的电子致密颗粒，这些颗粒可能由脂蛋白组成，可能是卵黄物质的前体。
The giant Antarctic paranthurid Accalathura gigantissima Kussakin (Crustacea, Isopoda) is adapted towards the predation of amphipods, which are pierced and sucked out by means of specialized mouthparts. Oesophagus and stomach pump the food first into the highly dilatable hindgut, later the chyme is transported into the digestive glands, whereby larger particles are retained in the intestine by the filters of the stomach. The ultrastructure of the hindgut shows the features of a transporting epithelium, no indications for secretion of digestive enzymes, intracellular digestion or storage of lipids or glycogen could be found. The digestive glands have very active cells which are responsible for resorption and secretion, intracellular digestion and storage of lipids (probably triglycerides). Lipids are metabolized and transported without the presence of SER, which is replaced by RER. Adipose tissue is present between muscles and forms laterally and ventrally a hypodermal fat body that can be rather voluminous in female specimens. The adipocytes of the studied immature females contained besides lipids and glycogen a large number of electron-dense granula probably composed of lipoproteins, which might be precursors of yolk material.