REGULATION OF DEVELOPMENT OF PEPTIDE NEURONS IN GUT

在肠道中发现了大量的肽能神经元。证据来自 我们和其他人最近的实验表明，环境 一般说来，尤其是肠道可以影响到 多肽表型。我们建议研究肠道中的元素 环境是影响多肽表达的关键因素。 利用体内和体外培养技术，我们将研究生产 在鹌鹑睫状神经节-雏鸡的神经肠道组合中神经肽的研究。 睫状神经节神经元原位仅含乙酰胆碱 神经肽生长抑素。我们将用体内培养的方法来研究 神经肠对纤毛神经肽表达的促进作用 绒毛尿囊膜上生长的神经节-肠组织复合体 寄养小鸡胚胎。这种方法将允许对 肠道年龄、肠道区域和肠道神经支配的变量对胃肠道功能的影响 神经肽在这样的环境中，三维组织完整性和 胚胎的荷尔蒙环境被保存下来。使用体外方法我们 将分析神经肽在生长的睫状神经节中的表达 不同年龄段的肠道文化媒体。这种方法将使我们能够 确定可溶性因子或细胞间接触是否对 多肽表达。在最后一组实验中，肠道的能力 组织提取物对中脑神经肽表达的影响 将对冠层培养进行研究。中脑神经的一部分 CREST是睫状神经节的前身。多肽包括 血管活性肠肽、生长抑素、脑啡肽和P物质 将通过免疫细胞化学进行定位，并通过放射免疫分析进行测量。 因为神经肽和胆碱能之间可能有联系 表达，我们将研究神经肽和 ChAT是胆碱能神经元特有的酶标记物。有了这个 结合各种技术，我们将阐明肠道中的元素 影响神经肽表达的环境。这些信息 在这里获得的信息将有助于理解 导致临床症状，如先天性巨结肠和 假性梗阻。

Peptidergic neurons are found in great numbers in the gut. Evidence from our recent experiments and those of others indicates that the environment in general and the gut in particular can influence the expression of peptide phenotypes. We propose to investigate the elements in the gut environment that are critical for influencing peptide expression. Using in vivo and in vitro culture techniques, we will study the production of neuropeptides in quail ciliary ganglion-chick aneural gut combinations. Ciliary ganglion neurons in situ contain only acetylcholine and the neuropeptide somatostatin. We will study with in vivo culture methods the ability of aneural gut to promote expression of neuropeptides in ciliary ganglion-gut tissue combinations grown on the chorioallantoic membrane of host chick embryos. This approach will permit an evaluation of the variables of gut age, gut region, and gut innervation on the production of neuropeptides in a setting where the three-dimensional tissue integrity and the hormonal milieu of the embryo are preserved. Using in vitro methods we will analyze the expression of neuropeptides in ciliary ganglia grown in culture media with gut of different ages. This approach will permit us to determine if a soluble factor or cell-to-cell contact is important to peptide expression. In a last set of experiments the ability of the gut and tissue extracts to influence peptide expression in mesencephalic neural crest cultures will be studied. A portion of the mesencephalic neural crest is a precursor for the ciliary ganglion. Peptides including vasoactive intestinal peptide, somatostatin, enkephalin and substance P will be localized by immunocytochemistry and measured by radioimmunoassay. Because there may be a link between neuropeptide and cholinergic expression, we will study the possible co-localization of neuropeptides and ChAT, an enzyme marker specific for cholinergic neurons. With this combination of techniques, we will elucidate the elements in the gut environment that influence neuropeptide expression. The information obtained here will be useful in understanding the underlying defects that lead to clinical conditions such as Hirschsprung's disease and pseudo-obstruction.