大鼠中缝背核一氧化氮合酶神经元投射纤维在大脑皮质微血管的分布

Distribution of nitric oxide synthase neurons projecting fibers of dorsal raphe nucleus in rat cortex microvessels

目的:研究通过损毁脑干中缝背核(DR),探讨中缝背核NOS阳性神经元是否投射分布于大脑皮质微血管。方法:将16只SD雄性成年大鼠分为实验组与对照组。对实验组大鼠中缝背核微量注射喹啉酸,饲养1w,灌注固定,然后将大脑及脑干作冠状冰冻切片,NADPH-d组化染色。结果:实验组大鼠的中缝背核被有效损毁,其NOS阳性神经元的数量减少了59.1％(P<0.001)。额、顶叶皮质NOS阳性纤维终末减少了32.1％(P<0.05),其中附着于皮质微血管的NOS阳性纤维终末了减少了37.8％(P<0.01)。而枕颞叶皮质NOS阳性纤维终末也减少了32.8％(P<0.05),其中附着于皮质微血管的阳性纤维终末减少了39.4％(P<0.01)。结论:位于中缝背核的NOS阳性神经元投射分布于大脑皮质微血管,可能参与大脑皮质血流量的调节。

Objective:To study the distribution of nitric oxide synthase (NOS) containing fibers from the dorsal raphe nucleus projecting to the cerebral microvessels. Methods:Totally 16 male adult SD rats were divided into 2 groups. The experimental group were microinjected with quisqualic acid,and raised for a week, then they were perfusion-fixed, the brain were sectioned and stained by the NADPH-d histochemistry. Results: The NOS-positive neurons in dorsal raphe nucleus decreased significantly by 59.1% (P < 0.001). The NOS positive terminals decreasd by 32.1% (P < 0.05) in the frontal-parietal cortex,and the NOS positive terminals associated with microvessels decreased by 37.8%(P<0.01), 32.8%(P<0.05) and 39.4%(P<0.01) in occipital,temporal cortex,respectively. Conclusiomlt is suggested that the NOS-containing neurons in dorsal raphe nucleus projecting to the microvessels in cerebral cortex.