Ding Kui, Zhang Libin, Fan Xinhao, Guo Xueying, Liu Xiang, Yang Hongsheng
CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
Front Physiol. 2020 Oct 22;11:559348. doi: 10.3389/fphys.2020.559348. eCollection 2020.
Neuropeptides are endogenous active substances that are present in nervous tissues and participate in behavioral and physiological processes of the animal system. Locomotor behavior is basic to predation, escape, reproduction in animals, and neuropeptides play an important role in locomotion. In this study, the function of pedal peptide-type neuropeptide (PDP) in the process of locomotor behavior of the sea cucumber was evaluated. The locomotor behavior of was recorded by infrared camera before and after PDP administration, and muscle physiology was studied by ultra performance liquid chromatography and quadrupole time-off-light mass spectrometry (UPLC-Q-TOF-MS) to clarify the potential physiological mechanisms. The results showed that PDP enhanced the cumulative duration of moving significantly at the 7th h after injection, and reduced the mean and maximum velocity by 16.90 and 14.22% in . The data of muscle metabolomics suggested that some significantly changed metabolites were related to locomotor behavior of sea cucumbers. The decreases of phosphatidylethanolamine (PE) and phosphatidylcholine (PC) might result in the increases of lysophosphatidylcholines (lysoPC) and lysophosphatidylethanolamine (lysoPE), and suggested the change of fluidity and permeability in the muscle cell membrane, which would affect the physiology and function of muscle cells, and finally alter the locomotor behavior. In addition, the increased level of arachidonic acid (ARA) might activate K ion channels and then affect the signaling of muscle cells, or promote the sensitivity of muscle cells to Ca and then result in the contractility of longitudinal muscles in sea cucumbers. ARA was also involved in the linoleic acid metabolism which was the only pathway that disturbed significantly after PDP administration. In conclusion, PDP participated in the regulation of locomotor behavior in the sea cucumber, and the decreased PE and PC, increased lysoPC, lysoPE and ARA might be the potential physiological mechanisms that responsible for behavioral effects of PDP in .
神经肽是存在于神经组织中并参与动物系统行为和生理过程的内源性活性物质。运动行为是动物捕食、逃避、繁殖的基础，神经肽在运动中发挥重要作用。本研究评估了踏板肽型神经肽（PDP）在海参运动行为过程中的功能。在给予PDP前后，用红外摄像机记录海参的运动行为，并通过超高效液相色谱和四极杆飞行时间质谱（UPLC-Q-TOF-MS）研究肌肉生理学，以阐明潜在的生理机制。结果表明，PDP在注射后第7小时显著延长了移动的累积持续时间，并使海参的平均速度和最大速度分别降低了16.90%和14.22%。肌肉代谢组学数据表明，一些显著变化的代谢物与海参的运动行为有关。磷脂酰乙醇胺（PE）和磷脂酰胆碱（PC）的减少可能导致溶血磷脂酰胆碱（lysoPC）和溶血磷脂酰乙醇胺（lysoPE）的增加，提示肌肉细胞膜流动性和通透性的改变，这将影响肌肉细胞的生理和功能，最终改变运动行为。此外，花生四烯酸（ARA）水平的升高可能激活钾离子通道，进而影响肌肉细胞的信号传导，或提高肌肉细胞对钙的敏感性，进而导致海参纵肌的收缩性。ARA还参与了亚油酸代谢，这是给予PDP后唯一显著紊乱的途径。总之，PDP参与了海参运动行为的调节，PE和PC的减少、lysoPC、lysoPE和ARA的增加可能是PDP在海参中产生行为效应的潜在生理机制。
