大鼠上丘一氧化氮合酶阳性神经元的发育

Ontogeny of the nitric oxide synthase positive neurons in rat superior colliculus

目的 :研究大鼠胚胎时期及生后早期一氧化氮合酶 ( NOS)阳性神经元在上丘的分布 ,进一步探讨一氧化氮 ( NO)在上丘发育过程中的作用。方法 :应用还原型尼克酰胺腺嘌呤二核苷酸脱氢酶 ( NADPH- d)组织化学方法观察孕 17d起至生后 14d大鼠上丘 NOS阳性神经元的发育。结果 :孕 2 0 d上丘深白层与深灰层出现 NOS阳性神经元。P0上丘中层也观察到 NOS阳性神经元。随着发育 ,阳性神经元增多 ,胞体增大 ,染色加深。到 P14,视神经层出现少许 NOS阳性神经元 ,浅灰层观察到大量的 NOS阳性神经元。结论 :胚胎 2 0天上丘深层首先出现 NOS阳性神经元并沿腹背方向发生 ,提示

Objective:In the present study,we observed the distribution of nitric oxide synthase(NOS) positive neurons in the developing rat superior colliculus(SC) to inquire into the possible roles of NO in SC development further.Methods:NADPH-d histochemical method was used to investigate the development of NOS positive neurons in rat SC from embryonic day 17(E17) to postnatal day 14(P14).Result:At E20,the first NOS positive neurons appeared in the deep white layer and deep gray layer.At P0,labeled neurons were also seen in the intermediate layer of SC.The number and intensity of the NOS positive neurons increased progressively during development.By P14,a few labeled neurons were present in the optic nerve layer and many positive neurons were observed in the superficial gray layer.Conclusion:NOS expression occurs in the deep layer of SC and progresses in a ventral to dorsal pattern,providing additional evidence that the NO may play an important role in the development of SC.