Hearn C, Newgreen D
The Murdoch Childrens Research Institute, Parkville, Victoria, Australia.
Dev Dyn. 2000 Jul;218(3):525-30. doi: 10.1002/1097-0177(200007)218:3<525::AID-DVDY1003>3.0.CO;2-7.
Most of the avian enteric nervous system is derived from the vagal neural crest, but a minority of the neural cells in the hindgut, and to an even lesser extent in the midgut, are of lumbo-sacral crest origin. Since the lumbo-sacral contribution was not detected or deemed negligible in the absence of vagal cells, it had been hypothesised that lumbo-sacral neural crest cells require vagal crest cells to contribute to the enteric nervous system. In contrast, zonal aganglionosis, a rare congenital human bowel disease led to the opposite suggestion, that lumbo-sacral cells could compensate for the absence of vagal cells to construct a complete enteric nervous system. To test these notions, we combined E4 chick midgut and hindgut, isolated prior to arrival of neural precursors, with E1. 7 chick vagal and/or E2.7 quail lumbo-sacral neural tube as crest donors, and grafted these to the chorio-allantoic membrane of E9 chick hosts. Double and triple immuno-labelling for quail cells (QCPNA), neural crest cells (HNK-1), neurons and neurites (neurofilament) and glial cells (GFAP) indicated that vagal crest cells produced neurons and glia in large ganglia throughout the entire intestinal tissues. Lumbo-sacral crest contributed small numbers of neurons and glial cells in the presence or absence of vagal cells, chiefly in colorectum, but not in nearby small intestinal tissue. Thus for production of enteric neural cells the avian lumbo-sacral neural crest neither requires the vagal neural crest, nor significantly compensates for its lack. However, enteric neurogenesis of lumbo-sacral cells requires the hindgut microenvironment, whereas that of vagal cells is not restricted to a particular intestinal region.
大多数鸟类的肠神经系统起源于迷走神经嵴，但后肠中的少数神经细胞，中肠中的则更少，起源于腰骶嵴。由于在没有迷走神经细胞的情况下未检测到腰骶部的贡献或认为其可忽略不计，因此有人推测腰骶神经嵴细胞需要迷走神经嵴细胞才能对肠神经系统做出贡献。相比之下，一种罕见的先天性人类肠道疾病——带状无神经节症则提出了相反的观点，即腰骶部细胞可以弥补迷走神经细胞的缺失，构建完整的肠神经系统。为了验证这些观点，我们将在神经前体到达之前分离的E4鸡中肠和后肠，与E1.7鸡迷走神经和/或E2.7鹌鹑腰骶神经管作为嵴供体相结合，并将其移植到E9鸡宿主的绒毛尿囊膜上。对鹌鹑细胞（QCPNA）、神经嵴细胞（HNK-1）、神经元和神经突（神经丝）以及神经胶质细胞（GFAP）进行双重和三重免疫标记表明，迷走神经嵴细胞在整个肠道组织的大神经节中产生神经元和神经胶质细胞。无论有无迷走神经细胞，腰骶嵴都贡献了少量的神经元和神经胶质细胞，主要在结肠直肠，但不在附近的小肠组织中。因此，对于肠神经细胞的产生，鸟类的腰骶神经嵴既不需要迷走神经嵴，也不能显著弥补其缺失。然而，腰骶部细胞的肠神经发生需要后肠微环境，而迷走神经细胞的肠神经发生并不局限于特定的肠道区域。
