γ-氨基丁酸B（GABA(B)）受体的刺激会增加大鼠视交叉上核区域的血清素释放。

The stimulation of GABA(B) receptors increases serotonin release in the rat suprachiasmatic area.

作者信息

François-Bellan A M, Hery M, Barrit M C, Faudon M, Hery F

机构信息

INSERM-U6 and CNRS-UA634, 280, Bd Sainte-Marguerite, 13009 Marseille, France.

出版信息

Neurochem Int. 1987;11(1):55-62. doi: 10.1016/0197-0186(87)90148-3.

DOI:10.1016/0197-0186(87)90148-3

PMID:20501142

Abstract

The action of ?-aminobutyric acid (GABA) and related compounds on the spontaneous release of newly synthesized [(3)H]5-hydroxytryptamine ([(3)H]5-HT) was studied in the suprachiasmatic area (SCA) using a superfusion system. GABA (10 ?M) increased [(3)H]5-HT release from SCA by up to 190%. Bicuculline or picrotoxin (10 ?M) failed to inhibit the stimulatory effect of GABA. Muscimol (10 ?M), a GABA(A) agonist, was ineffective, however ?-p-chlorophenyl GABA, R(?)baclofen, enhanced over 200% the release of the indoleamine; this latter effect was stereospecific. RS baclofen was twice less potent than the R(?)isomer in increasing the [(3)H]5-HT release. S(+)baclofen failed to affect the release of the indoleamine, whereas it attenuated the effect of its enantiomer. The effect of R(?)baclofen was Ca(2+) dependent and was abolished by tetrodotoxin (TTX). Taken together these results suggest that in the SCA, [(3)H]5-HT release is facilitated by the stimulation of GABA(B) receptors. The possible localization of these receptors is discussed in the light of morphological data recently reported by Bosler et al. (1985) and results obtained after TTX application.

摘要

利用灌流系统，在视交叉上核区域（SCA）研究了γ-氨基丁酸（GABA）及相关化合物对新合成的[（3）H]5-羟色胺（[（3）H]5-HT）自发释放的作用。GABA（10 μM）可使SCA中[（3）H]5-HT的释放增加高达190%。荷包牡丹碱或印防己毒素（10 μM）未能抑制GABA的刺激作用。GABA（A）激动剂蝇蕈醇（10 μM）无效，然而，γ-对氯苯基GABA、R（-）巴氯芬可使吲哚胺的释放增加超过200%；后一种作用具有立体特异性。在增加[（3）H]5-HT释放方面，RS巴氯芬的效力比R（-）异构体低两倍。S（+）巴氯芬未能影响吲哚胺的释放，而它减弱了其对映体的作用。R（-）巴氯芬的作用依赖于Ca（2+），并被河豚毒素（TTX）消除。综上所述，这些结果表明在SCA中，[（3）H]5-HT的释放通过GABA（B）受体的刺激而促进。根据Bosler等人（1985年）最近报道的形态学数据以及TTX应用后获得的结果，讨论了这些受体可能的定位。