摘要
目的 :解释棕色田鼠 (Microtusmandarinus)消化道对其生活史特征的适应性调节机制。 方法 :用NADPH 黄递酶组织化学法对NOS在棕色田鼠胃肠肌间神经丛的分布进行比较研究。 结果 :棕色田鼠胃肠肌间神经丛NOS阳性神经元形态各异 ,大小悬殊数倍 ;神经节和阳性神经纤维构成网络结构 ,阳性神经元可呈“串珠”状和“U”形排列。NOS阳性神经元分布密度在胃肠道各段差异较大 :结肠密度最高 ,回肠次之 ,胃和盲肠比回肠低 ,比十二指肠和空肠高。结论 :棕色田鼠NOS阳性神经元在胃肠道各节段肌间神经丛的分布特点可能是与其食性和生理机能相适应的。
Objective: To interpret the adaptive regulating mechanism of the Microtus mandarinus digestive tract to its life history. Methods: The distribution of nitric oxide synthase (NOS)-containing neurons in the gastrointestinal tract of the Microtus mandarinus was studied with NADPH-diaphorase histochemistry. Results: 1) The shape and size of the NOS positive neurons were varied. 2) The ganglia and positive nerve fibers formed complex meshwork, and there existed beads-shaped and U-shaped structure. 3) There was a significant regional variation along the gastrointestinal axis in the density of NOS positive neurons: the highest was in the colon, the second was in the ileum, and the density in the stomach and the cecum was lower than that in the ileum, but higher than that in the duodenum and the jejunum. Conclusion: The feature of NOS positive neuron distribution in myenteric plexus of various segments of the Microtus mandarinus digestive tract probably adapts to its feeding habit and physiological function of digest.
