Cox B A, Johnson S W
Department of Physiology and Pharmacology, Oregon Health Sciences University, Portland 97201, USA.
Neurosci Lett. 1998 Oct 23;255(3):131-4. doi: 10.1016/s0304-3940(98)00737-x.
Dopamine (DA) neurons in the ventral tegmental area and substantia nigra pars compacta were induced to fire in bursts with application of N-methyl-D-aspartate (NMDA, 20 microM) and apamin (100 nM) while recording intracellularly in the rat brain slice. L-Arginine (300 microM), a substrate for nitric oxide (NO) production, increased both the number of spikes per burst and the magnitude of interburst hyperpolarizations. Nitric oxide synthase inhibitors N-nitro-L-arginine methyl ester (L-NAME, 100 microM), N-nitro-L-arginine, and 7-nitroindazole inhibited NMDA-induced burst firing by reducing the number of spikes per burst. Moreover, L-arginine (100 microM) reversed the inhibition of burst firing produced by L-NAME. These findings suggest that NO facilitates NMDA-induced burst firing in DA neurons.
在大鼠脑片中进行细胞内记录时，腹侧被盖区和黑质致密部的多巴胺（DA）神经元在应用N-甲基-D-天冬氨酸（NMDA，20微摩尔）和蜂毒明肽（100纳摩尔）后被诱导成簇放电。L-精氨酸（300微摩尔）是一氧化氮（NO）生成的底物，它增加了每个簇的尖峰数量以及簇间超极化的幅度。一氧化氮合酶抑制剂N-硝基-L-精氨酸甲酯（L-NAME，100微摩尔）、N-硝基-L-精氨酸和7-硝基吲唑通过减少每个簇的尖峰数量来抑制NMDA诱导的簇状放电。此外，L-精氨酸（100微摩尔）逆转了L-NAME对簇状放电的抑制作用。这些发现表明，NO促进了DA神经元中NMDA诱导的簇状放电。
