The mesenterial tissues play important roles in the interactions between the viscera and the rest of the organism. Among these roles, they serve as the physical substrate for nerves connecting the visceral nervous components to the central nervous system. Although the mesenterial nervous system component has been described in vertebrates, particularly in mammals, a description in other deuterostomes is lacking. Using immunohistochemistry in tissue sections and whole mounts, we describe here the nervous component of the intestinal mesentery in the sea cucumber Holothuria glaberrima. This echinoderm has the ability to regenerate its internal organs in a process that depends on the mesentery. Therefore, we have also explored changes in the mesenterial nervous component during intestinal regeneration. Extensive fiber bundles with associated neurons are found in the mesothelial layer, extending from the body wall to the intestine. Neuron-like cells are also found within a plexus in the connective tissue layer. We also show that most of the cells and nerve fibers within the mesentery remain during the regenerative process, with only minor changes: a general disorganization of the fiber bundles and a retraction of nerve fibers near the tip of the mesentery during the first days of regeneration. Our results provide a basic description of mesenterial nervous component that can be of importance for comparative studies as well as for the analyses of visceral regeneration.

中文翻译：

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正常和再生动物海参肠系膜的神经系统组成部分


肠系膜组织在内脏与生物体其他部分之间的相互作用中发挥着重要作用。在这些作用中，它们充当将内脏神经成分连接到中枢神经系统的神经的物理基质。尽管已在脊椎动物，特别是哺乳动物中描述了肠系膜神经系统成分，但缺乏对其他后口动物的描述。利用组织切片和整体免疫组织化学，我们在此描述了海参 Holothuria glaberrima 肠系膜的神经成分。这种棘皮动物具有依靠肠系膜再生其内脏器官的能力。因此，我们还探讨了肠再生过程中肠系膜神经成分的变化。在间皮层中发现了具有相关神经元的广泛纤维束，从体壁延伸到肠道。神经元样细胞也存在于结缔组织层的神经丛内。我们还表明，肠系膜内的大多数细胞和神经纤维在再生过程中仍然存在，只有微小的变化：在再生的第一天，纤维束普遍解体，肠系膜尖端附近的神经纤维回缩。我们的结果提供了肠系膜神经成分的基本描述，这对于比较研究以及内脏再生分析具有重要意义。