Stimulation of the ventral subiculum of the hippocampus evokes glutamate receptor-mediated changes in dopamine efflux in the rat nucleus accumbens
Stimulation of the ventral subiculum of the hippocampus evokes glutamate receptor-mediated changes in dopamine efflux in the rat nucleus accumbens
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DOI：
10.1111/j.1460-9568.1997.tb01441.x
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发表时间：
1997-05-01
影响因子：
3.4
通讯作者：
Phillips, AG
中科院分区：
文献类型：
--
作者：
Blaha, CD;Yang, CR;Phillips, AG
采用硬脂酸-石墨糊电极在体计时电流法研究了电刺激海马腹侧下托/CA 1区对延髓核多巴胺氧化电流（对应于多巴胺流出）变化的影响。爆发模式的双相脉冲（10-100 Hz/0.8-4 Hz的爆发）诱发了延髓核多巴胺流出的三种成分变化，多巴胺信号最初短暂增加高于基线，随后立即降低低于基线，此后多巴胺信号延长增加高于基线。6-羟多巴胺损伤中脑多巴胺通路或切断穹窿海马伞阻断了多巴胺信号的所有诱发变化。第一和第三组分的增强多巴胺流出被阻断的离子型谷氨酸受体拮抗剂（+/-）-2-氨基-5-膦戊酸，6，7-二硝基喹喔啉-2，3-二酮和犬尿酸的微输注到脑桥核。向延髓核微量注入代谢型谷氨酸受体拮抗剂（+）-α-甲基-4-羧基苯甘氨酸后，猝发刺激诱发的多巴胺信号降低被消除。这些结果表明，腹侧下托/CA 1神经递质输入到丘脑核可能突触前调节多巴胺流出的突触激活的亲离子型和亲代谢型谷氨酸受体在丘脑核。这些谷氨酸-多巴胺相互作用可能构成海马信号通过选择性调节在生理和病理条件下丘脑核中多巴胺释放而整合的机制的一部分。
The effects of electrical stimulation of the ventral subiculum/CA1 region of the hippocampus on changes in dopamine oxidation current (corresponding to dopamine efflux) in the nucleus accumbens were examined using in vivo chronoamperometry with stearate-graphite paste electrodes in urethane-anaesthetized rats. Burst-patterned monophasic pulses (10-100 Hz/burst delivered at 0.8-4 Hz) evoked a three-component change in dopamine efflux in the nucleus accumbens with an initial transient increase in the dopamine signal above baseline, followed by an immediate decrease below baseline, and thereafter by a prolonged increase in the dopamine signal above baseline. 6-Hydroxydopamine lesions of the mesoaccumbens dopamine pathway or transection of the fimbria-fornix blocked all of the evoked changes in the dopamine signal. Both the first and third components of enhanced dopamine efflux were blocked by microinfusion into the nucleus accumbens of the ionotropic glutamate receptor antagonists (+/-)-2-amino-5-phosphonopentanoic acid, 6,7-dinitroquinoxaline-2,3-dione and kynurenate. Burst stimulation-evoked decreases in the dopamine signal were abolished following microinfusions into the nucleus accumbens of the metabotropic glutamate receptor antagonist (+)-alpha-methyl-4-carboxyphenylglycine. These results suggest that ventral subiculum/CA1 glutamatergic inputs to the nucleus accumbens may presynaptically modulate dopamine efflux by synaptic activation of both ionotropic and metabotropic glutamate receptors in the nucleus accumbens. These glutamate-dopamine interactions may constitute part of the mechanisms by which hippocampal signals are integrated through selective modulation of dopamine release in the nucleus accumbens in both physiological and pathological conditions.