Chevalier N R, Fleury V, Dufour S, Proux-Gillardeaux V, Asnacios A
Laboratoire Matière et Systèmes Complexes, Université Paris Diderot/CNRS UMR 7057, Sorbonne Paris Cité, Paris, France.
INSERM, U955, Equipe 6, France & Université Paris Est, Faculté de médecine, Créteil, France.
PLoS One. 2017 Feb 21;12(2):e0172511. doi: 10.1371/journal.pone.0172511. eCollection 2017.
The gastrointestinal tract transports the food bolus by peristalsis. Gut motility starts at an early age in the developing embryo, well before it is required for nutrition of the organism. We present a comprehensive kinematic study of the emergence and physiological development of gut motility in all regions of the lower digestive tract of the chicken embryo from embryonic days E5 through E9. We characterized motility emergence time, propagation patterns, speed, frequency and amplitude of peristalsis waves. We found that the emergence of an uninterrupted circular ring of smooth muscle correlated with the appearance of propagative contractile waves, at E6 in the hindgut and midgut, and at E9 in the caecal appendix. We show that peristalsis at these stages is critically dependent on calcium and is not mediated by neurons as gut motility is insensitive to tetrodotoxin and takes place in the hindgut in the absence of neurons. We further demonstrate that motility also matures in ex-vivo organ culture. We compare our results to existing literature on zebrafish, mouse and human motility development, and discuss their chronological relationship with other major developmental events occurring in the chicken embryonic gut at these stages. Our work sets a baseline for further investigations of motility development in this important animal model.
胃肠道通过蠕动运送食团。肠道蠕动在发育中的胚胎早期就开始了，远早于机体营养所需的时间。我们对鸡胚从胚胎第5天（E5）到第9天（E9）下消化道所有区域肠道蠕动的出现及生理发育进行了全面的运动学研究。我们对蠕动出现的时间、传播模式、速度、频率和蠕动波幅度进行了表征。我们发现，在E6时后肠和中肠出现连续的平滑肌环，这与传播性收缩波的出现相关，而盲肠附件在E9时出现这种情况。我们表明，这些阶段的蠕动严重依赖于钙，且不是由神经元介导的，因为肠道蠕动对河豚毒素不敏感，并且在没有神经元的后肠中也会发生。我们进一步证明，在体外器官培养中蠕动也会成熟。我们将我们的结果与关于斑马鱼、小鼠和人类运动发育的现有文献进行比较，并讨论它们与这些阶段鸡胚肠道中发生的其他主要发育事件的时间关系。我们的工作为进一步研究这个重要动物模型中的运动发育奠定了基础。
