γ-氨基丁酸（GABA）和L-谷氨酸对大鼠纹状体和黑质中钾离子诱发的P物质和神经激肽A样免疫反应性体外释放的影响不同。

Effects of GABA and L-glutamic acid on the potassium-evoked in vitro release of substance P- and neurokinin A-like immunoreactivities are different in the rat striatum and substantia nigra.

作者信息

Humpel C, Saria A

机构信息

Department of Psychiatry, University Hospital Innsbruck, Austria.

出版信息

Neurosci Lett. 1989 Oct 23;105(1-2):159-63. doi: 10.1016/0304-3940(89)90029-3.

DOI:10.1016/0304-3940(89)90029-3

PMID:2484728

Abstract

Slices of the rat substantia nigra and striatum were superfused in vitro to measure release of tachykinins (TKs). Potassium (30 and 60 mM) infusion caused a 3- to 10-fold outflow of both substance P-like immunoreactivity (SP-LI) and neurokinin A-like immunoreactivity (NKA-LI) in the substantia nigra as well as in the striatum as measured by radioimmunoassay. The potassium-evoked release of SP-LI and NKA-LI was significantly, but not completely (by 25-70%) inhibited by simultaneous perfusion with L-glutamic acid (50 microM) and gamma-aminobutyric acid (GABA, 50 microM) in the substantia nigra. No significant inhibition was, however, observed in the striatum. The present data indicate a differential regulation of tachykinins in the striatum and substantia nigra by L-glutamic acid and GABA. The presynaptic regulation of TK release may therefore differ in the dendritic and terminal region of the striatonigral pathway.

摘要

将大鼠黑质和纹状体切片进行体外灌流，以测量速激肽（TKs）的释放。通过放射免疫测定法测得，灌注钾（30和60 mM）导致黑质以及纹状体中P物质样免疫反应性（SP-LI）和神经激肽A样免疫反应性（NKA-LI）流出量增加3至10倍。在黑质中，同时灌注L-谷氨酸（50 microM）和γ-氨基丁酸（GABA，50 microM）可显著但不完全（25%-70%）抑制钾诱发的SP-LI和NKA-LI释放。然而，在纹状体中未观察到显著抑制作用。目前的数据表明，L-谷氨酸和GABA对纹状体和黑质中的速激肽有不同的调节作用。因此，速激肽释放的突触前调节在纹状体黑质通路的树突和终末区域可能有所不同。