Peterson S L, St Mary J S, Harding N R
Brain Res Bull. 1987 Jun;18(6):723-9. doi: 10.1016/0361-9230(87)90207-3.
This study was designed to characterize the response of a select population of prefrontal cortex neurons to exogenous and endogenous dopaminergic influences. Of particular interest were neurons with efferent projections to the ventral tegmental area (VTA) which are part of a reciprocal innervation between the prefrontal cortex and the VTA. Extracellular single unit recording techniques were used to determine the response of cortical neurons to electrical stimulation of the VTA in chloral hydrate anesthetized rats. The neurons were selected on the basis of their electrophysiological characteristics (large amplitude with positive initial deflection) and were classified as to whether or not they were antidromically activated from the VTA. Apomorphine (25 micrograms/kg, IV) significantly reduced the spontaneous activity of both the antidromically identified and the unidentified prefrontal cortex neurons. The apomorphine (25 micrograms/kg, IV) response was antagonized by cis-flupentixol (1.0 mg/kg, IV) in both antidromically identified and unidentified cortical neurons. Stimulation of the VTA also induced a synaptically mediated inhibition of the cortical neuron spontaneous activity. The orthodromic VTA stimulus-evoked inhibition was antagonized by cis-flupentixol (1.0 mg/kg, IV) for both the antidromically identified and the unidentified neurons (63 and 71% of the neurons respectively). The results indicate that a select population of prefrontal cortex neurons respond specifically to exogenous and endogenous dopaminergic influences and that the response is independent of efferent projections to the VTA.
本研究旨在表征前额叶皮质特定神经元群体对外源性和内源性多巴胺能影响的反应。特别令人感兴趣的是那些具有传出投射至腹侧被盖区（VTA）的神经元，腹侧被盖区是前额叶皮质与腹侧被盖区之间相互神经支配的一部分。采用细胞外单单位记录技术，以确定水合氯醛麻醉大鼠中皮质神经元对腹侧被盖区电刺激的反应。根据神经元的电生理特性（初始偏转呈正向的大幅度）进行选择，并根据它们是否能被腹侧被盖区逆向激活进行分类。阿扑吗啡（25微克/千克，静脉注射）显著降低了逆向识别的和未识别的前额叶皮质神经元的自发活动。在逆向识别的和未识别的皮质神经元中，顺式氟哌噻吨（1.0毫克/千克，静脉注射）均拮抗了阿扑吗啡（25微克/千克，静脉注射）的反应。刺激腹侧被盖区也诱导了对皮质神经元自发活动的突触介导抑制。对于逆向识别的和未识别的神经元，顺式氟哌噻吨（1.0毫克/千克，静脉注射）均拮抗了顺向腹侧被盖区刺激诱发的抑制（分别为63%和71%的神经元）。结果表明，前额叶皮质特定神经元群体对外源性和内源性多巴胺能影响有特异性反应，且该反应独立于至腹侧被盖区的传出投射。
