大鼠肠道内ACh能、SP、VIP-肽能和NO能神经的分布模式及相互关系

目的 比较观察大鼠肠道内乙酰胆碱酯酶(acetylcholinesterase,ACHE)、P物质(substance P,SP)、血管活性肠肽(vasoactive intestinal polypeptide,VIP)和一氧化氮合酶(nitric oxide synthase,NOS)4种阳性神经元的分布特征及其相互关系.方法 应用酶组织化学和免疫组织化学技术,分别观察AChE、NOS、SP、VIP阳性神经元在大鼠十二指肠、空肠、回肠、结肠和直肠的分布.结果 4种阳性神经元(胞体和纤维)遍布肠壁各层,其分布状态有相随性和相似性规律,即从十二指肠、空肠到回肠逐渐增多,从结肠到直肠逐渐减少;AChE阳性神经元在肠壁各层都十分丰富,NOS和sP阳性神经元以肠肌丛较为丰富,VIP阳性神经元以黏膜下神经丛和黏膜层较为丰富;分布密度依次为AChE>NOS>VIP>SP.4种神经元彼此有共染(递质共存)现象,肠肌丛内神经元互相有突触样联系.结论 AChE、SP、VIP和NOS阳性神经元胞体及神经纤维在不同肠段的分布密度有明显差异,而肠肌丛内各种神经元在形态学上有密切联系,由此推论在肠动力功能调节上它们可能起协调作用.

A Comparative Study on the Distribution and Relationship of Cholinergic,SP, VIP-Peptidergic and Nitroergic Nerves in Intestinal Tract of Rats

Objective To study the distribution characteristics and relationship of acetylcholinesterase (AChE) .substance P(SP), vasoactive intestinal polypeptide (VIP) and nitric oxide synthase ( NOS)-positive neurons in intestinal tract of rats. Methods The distributions of AChE,SP, VIP and NOS-positive neurons in duodenum,jejunum,ileum,colon and rectum of rats were respectively observed by using enzyme histochemical and immunohistochemical methods. Results Four types of positive neurons distributed throughout in each laminae of intestinal tract of rats,and there was accompanying and resemble distribution regularity. From duodenum,jejunum to ileum,four types of positive neurons showed gradual increase tendency in quantity, while from colon to rectum, they showed gradual decrease tendency in quantity. There were extremely abundant AChE-posi-tive neurons in each laminae of intestinal tract of rats,comparatively rich NOS and SP-positive neurons in Auerbach'myenteric plexus(AMP) ,and comparatively rich VIP-ir positive neurons in the Meissner's submucosal plexus(MSP)and mucosa. Density on the distribution of four types of positive neurons was AChE>NOS>VIP>SP. There was coexistence of four types of neurons, and there were synapse-like contacts in four types of neurons in AMP. Conclusion There were significant differences in the density on the distribution of AChE,SP, VIP and NOS-positive neurons in different segments of intestinal tract of rats,and there was close morphological relationship among four types of neurons in AMP. It was deduced that they exerted synergistic effects in regulating motility of the intestine.