Gibson N J, Nighorn A
Arizona Research Laboratories, Division of Neurobiology, The University of Arizona, Tucson, Arizona 85721, USA.
J Comp Neurol. 2000 Jun 26;422(2):191-205. doi: 10.1002/(sici)1096-9861(20000626)422:2<191::aid-cne4>3.0.co;2-c.
The gaseous messenger nitric oxide (NO), with its ability to mediate both intercellular and intracellular communication, can play important roles in mediating cellular communication in both the development and the function of the nervous system. The authors investigated the possible role of NO signaling in the developing olfactory system (antennal lobe) of the moth Manduca sexta. NO synthase (NOS), the enzyme that generates NO, was localized by using immunocytochemistry, in situ hybridization, and nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry. Although NADPH-d staining appears to be a poor indicator of the presence of NOS in this system, immunocytochemistry and in situ hybridization reveal that NOS is expressed in the axons of olfactory receptor neurons throughout development and in the perineurial sheath that covers the brain early in development. NOS is present in axon terminals as they form protoglomeruli, raising the possibility that NO mediates cell-cell interactions during antennal lobe development. NO-sensitive soluble guanylyl cyclase (sGC), one of the best characterized targets of NO, was localized in the developing olfactory system by using in situ hybridization and immunocytochemistry for the Manduca sexta sGCalpha1 subunit. The ability of the developing olfactory system to respond to exogenous NO also was examined by using cyclic guanosine monophosphate immunocytochemistry. sGC is expressed in mechanosensory neurons in the developing antenna and in many antennal lobe neurons in both the medial and lateral cell body clusters. Thus, NOS and sGC are expressed in a pattern that suggests that this signaling pathway may mediate intercellular communication during development of the olfactory system in Manduca sexta.
气态信使一氧化氮（NO）具有介导细胞间和细胞内通讯的能力，在神经系统的发育和功能中，它在介导细胞通讯方面发挥着重要作用。作者研究了NO信号在烟草天蛾发育中的嗅觉系统（触角叶）中可能发挥的作用。通过免疫细胞化学、原位杂交和烟酰胺腺嘌呤二核苷酸磷酸黄递酶（NADPH-d）组织化学方法，对产生NO的酶——一氧化氮合酶（NOS）进行了定位。尽管在该系统中，NADPH-d染色似乎并不能很好地指示NOS的存在，但免疫细胞化学和原位杂交显示，在整个发育过程中，NOS在嗅觉受体神经元的轴突中表达，并且在发育早期覆盖大脑的神经周鞘中也有表达。当轴突终末形成原小球时，NOS就已存在，这增加了NO在触角叶发育过程中介导细胞间相互作用的可能性。通过对烟草天蛾sGCalpha1亚基进行原位杂交和免疫细胞化学，在发育中的嗅觉系统中对NO敏感的可溶性鸟苷酸环化酶（sGC）进行了定位，sGC是NO最具特征的靶标之一。还通过环磷酸鸟苷免疫细胞化学方法，检测了发育中的嗅觉系统对外源性NO的反应能力。sGC在发育中的触角的机械感觉神经元以及内侧和外侧细胞体簇中的许多触角叶神经元中均有表达。因此，NOS和sGC的表达模式表明，该信号通路可能在烟草天蛾嗅觉系统发育过程中介导细胞间通讯。
