PhyMedExp, University of Montpellier, INSERM, CNRS, 34295 Montpellier, France.
IPAM, Biocampus Montpellier, CNRS, INSERM, University of Montpellier, 34295 Montpellier, France.
Development. 2022 Aug 15;149(16). doi: 10.1242/dev.200625. Epub 2022 Aug 30.
Gastrointestinal motor activity has been extensively studied in adults; however, only few studies have investigated fetal motor skills. It is unknown when the gastrointestinal tract starts to contract during the embryonic period and how this function evolves during development. Here, we adapted a non-invasive high-resolution echography technique combined with speckle tracking analysis to examine the gastrointestinal tract motor activity dynamics during chick embryo development. We provided the first recordings of fetal gastrointestinal motility in living embryos without anesthesia. We found that, although gastrointestinal contractions appear very early during development, they become synchronized only at the end of the fetal period. To validate this approach, we used various pharmacological inhibitors and BAPX1 gene overexpression in vivo. We found that the enteric nervous system determines the onset of the synchronized contractions in the stomach. Moreover, alteration of smooth muscle fiber organization led to an impairment of this functional activity. Altogether, our findings show that non-invasive high-resolution echography and speckle tracking analysis allows visualization and quantification of gastrointestinal motility during development and highlight the progressive acquisition of functional and coordinated gastrointestinal motility before birth.
胃肠道运动在成人中已经得到了广泛的研究；然而，只有少数研究调查了胎儿的运动技能。目前还不清楚胃肠道在胚胎期何时开始收缩，以及这种功能在发育过程中是如何演变的。在这里，我们采用了一种非侵入性的高分辨率超声技术结合斑点跟踪分析，来研究鸡胚发育过程中胃肠道运动活动的动力学。我们首次在没有麻醉的活体胚胎中记录了胎儿的胃肠道蠕动。我们发现，尽管胃肠道收缩在发育过程中很早就出现了，但它们只在胎儿期末才变得同步。为了验证这种方法，我们在体内使用了各种药理学抑制剂和 BAPX1 基因过表达。我们发现，肠神经系统决定了胃同步收缩的开始。此外，平滑肌纤维组织的改变导致了这种功能活动的损伤。总之，我们的研究结果表明，非侵入性高分辨率超声和斑点跟踪分析可以在发育过程中可视化和定量胃肠道运动，并强调了在出生前功能性和协调性胃肠道运动的逐渐获得。
