Kimura T, Yu J G, Edvinsson L, Lee T J
Southern Illinois University School of Medicine, Department of Pharmacology, Springfield 62794-1222, USA.
Brain Res. 1997 Oct 31;773(1-2):117-24. doi: 10.1016/s0006-8993(97)00889-5.
Using immunoperoxidase labeling (IPL) and immunofluorescence labeling (IFL) methods, and each followed by NADPH diaphorase (NADPHd) histochemical staining in the same specimen, colocalization of choline acetyltransferase (ChAT) and NADPHd, indicative of nitric oxide synthase (NOS), in cerebral pial arteries and the sphenopalatine ganglia (SPG) of the cat was examined. In addition, retrograde axonal tracing using true blue was performed to determine if cerebral perivascular nerves containing ChAT and NADPHd originate in the SPG. Consistent results were obtained from IPL and IFL methods, indicating that the middle cerebral artery (MCA) and the circle of Willis received dense ChAT-immunoreactive (I) and NADPHd bundles and fine fibers. Almost all ChAT-I fibers and NADPHd fibers were found to be coincident in the arteries examined. A few fine fibers exhibited only NADPHd staining. In the SPG, approximately half of the ganglionic cells were both ChAT-I and NADPHd positive, while the remaining cells were positively only for NADPHd staining. One week after application of true blue on the middle cerebral arteries (MCA), the fluorescent true blue was found in the ganglionic cells of the SPG. Some of the true blue-positive cells contained both ChAT-immunoreactivity and NADPHd staining. These results provide morphological evidence indicating that all ChAT-I fibers in the MCA and the circle of Willis contain NOS, and that these fibers originate in the SPG, although not all NOS-I ganglionic cells in the SPG send fibers to pial vessels. These results also support the hypothesis that acetylcholine (ACh) and nitric oxide (NO) are synthesized and co-released in the same neurons in cerebral perivascular nerves. Based on the reported findings that NO mediates a major component of neurogenic vasodilation, and that ACh acts as a modulator, the present results demonstrate the presence of a cholinergic, nitric oxidergic innervation in cerebral arteries of the cat.
采用免疫过氧化物酶标记（IPL）和免疫荧光标记（IFL）方法，并在同一标本上依次进行NADPH黄递酶（NADPHd）组织化学染色，检测猫脑软膜动脉和蝶腭神经节（SPG）中胆碱乙酰转移酶（ChAT）与指示一氧化氮合酶（NOS）的NADPHd的共定位情况。此外，使用真蓝进行逆行轴突追踪，以确定含ChAT和NADPHd的脑周血管神经是否起源于SPG。IPL和IFL方法得到了一致的结果，表明大脑中动脉（MCA）和 Willis 环接受了密集的ChAT免疫反应性（I）和NADPHd束及细纤维。在所检查的动脉中，几乎所有ChAT-I纤维和NADPHd纤维都相互重合。少数细纤维仅显示NADPHd染色。在SPG中，约一半的神经节细胞ChAT-I和NADPHd均为阳性，而其余细胞仅NADPHd染色呈阳性。在大脑中动脉（MCA）上应用真蓝一周后，在SPG的神经节细胞中发现了荧光真蓝。一些真蓝阳性细胞同时含有ChAT免疫反应性和NADPHd染色。这些结果提供了形态学证据，表明MCA和Willis环中的所有ChAT-I纤维都含有NOS，且这些纤维起源于SPG，尽管SPG中并非所有NOS-I神经节细胞都向软膜血管发送纤维。这些结果还支持了乙酰胆碱（ACh）和一氧化氮（NO）在脑周血管神经的同一神经元中合成并共同释放的假说。基于已报道的发现，即NO介导神经源性血管舒张的主要成分，且ACh起调节剂作用，目前的结果证明了猫脑动脉中存在胆碱能、一氧化氮能神经支配。
