Reid M S, Herrera-Marschitz M, Kehr J, Ungerstedt U
Department of Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Acta Physiol Scand. 1990 Dec;140(4):527-37. doi: 10.1111/j.1748-1716.1990.tb09030.x.
The levels of extracellular striatal dopamine and glutamate were measured simultaneously in halothane-anaesthetized rats using microdialysis. Unilateral injections of substance P (0.07 nmol) into the substantia nigra, pars reticulata enhanced the levels of dopamine and glutamate in the ipsilateral striatum. Intranigral injections of neurokinin A (0.09 nmol) enhanced the levels of striatal dopamine, and intranigral injections of gamma-aminobutyric acid (300 nmol) or dynorphin A (0.5 nmol) decreased the levels of striatal dopamine, but none of these had any effect on the levels of striatal glutamate. Local perfusion with the dopamine agonists apomorphine (D1/D2), SKF 38393 (D1) or pergolide (D2) (each at 10(5) M) decreased the levels of striatal dopamine and enhanced the levels of striatal glutamate. In unilateral 6-hydroxydopamine-lesioned rats, basal striatal glutamate levels were decreased bilaterally. Furthermore, on the denervated side intranigral substance P stimulation of striatal glutamate levels was enhanced, while on the intact side intranigral substance P stimulation of striatal dopamine and glutamate levels was similar to that seen in normal rats. These findings suggest that striatonigral substance P provides a stimulatory regulation of ipsilateral striatal glutamate release. Furthermore, it is indicated that striatal glutamate release can also be regulated by dopamine terminals.
使用微透析技术，在氟烷麻醉的大鼠中同时测量细胞外纹状体多巴胺和谷氨酸的水平。向黑质网状部单侧注射P物质（0.07 nmol）可提高同侧纹状体中多巴胺和谷氨酸的水平。向黑质内注射神经激肽A（0.09 nmol）可提高纹状体多巴胺水平，而向黑质内注射γ-氨基丁酸（300 nmol）或强啡肽A（0.5 nmol）可降低纹状体多巴胺水平，但这些对纹状体谷氨酸水平均无影响。用多巴胺激动剂阿扑吗啡（D1/D2）、SKF 38393（D1）或培高利特（D2）（均为10⁻⁵ M）进行局部灌注可降低纹状体多巴胺水平并提高纹状体谷氨酸水平。在单侧6-羟基多巴胺损伤的大鼠中，双侧基底纹状体谷氨酸水平降低。此外，在去神经侧，黑质内P物质刺激可增强纹状体谷氨酸水平，而在完整侧，黑质内P物质刺激纹状体多巴胺和谷氨酸水平与正常大鼠相似。这些发现表明，纹状体黑质P物质对同侧纹状体谷氨酸释放具有刺激调节作用。此外，表明纹状体谷氨酸释放也可受多巴胺终末的调节。
