Hardy S G, Haigler H J
Brain Res. 1985 Jul 29;339(2):285-93. doi: 10.1016/0006-8993(85)90094-0.
After implanting stimulating electrodes in the prefrontal cortex (PFC) of adult male rats, the response to PFC stimulation was studied in widely scattered neurons of the midbrain. Subsequent testing was performed to determine if the firing rates of PFC-responsive neurons could also be altered by either a noxious stimulus (foot pinch) or the microiontophoretic administration of various neurotransmitter substances (methionine-enkephalin, ME; norepinephrine, NE; acetylcholine, ACh). Numerous mesencephalic neurons were identified which altered their spontaneous firing rates in response to PFC stimulation. Following PFC stimulation, most (71%) neurons decreased their firing rates. It was also noted that most (78%) PFC-responsive neurons were also responsive to noxious stimulation. Of these neurons, 65% altered their firing rates in a similar manner in response to both PFC and noxious stimuli. The remainder of the neurons which altered their firing rates in response to both PFC and noxious stimulation responded to the two types of stimuli in opposite manners. Of this latter type, it was found that when PFC and noxious stimuli were administered concurrently, PFC stimulation abolished the response to the noxious stimulus. It was also observed that the microiontophoretic administration of either ME or NE frequently (100% and 52% respectively) mimicked the response to PFC stimulation, thereby suggesting that these neurotransmitters may be involved in mediating the PFC influence upon neurons in the midbrain.
在成年雄性大鼠的前额叶皮质（PFC）植入刺激电极后，研究了中脑广泛分布的神经元对PFC刺激的反应。随后进行测试，以确定PFC反应性神经元的放电频率是否也会因有害刺激（夹脚）或微量离子电泳给予各种神经递质物质（甲硫氨酸脑啡肽，ME；去甲肾上腺素，NE；乙酰胆碱，ACh）而改变。确定了许多中脑神经元，它们在对PFC刺激的反应中改变了自发放电频率。在PFC刺激后，大多数（71%）神经元降低了放电频率。还注意到，大多数（78%）PFC反应性神经元也对有害刺激有反应。在这些神经元中，65%在对PFC和有害刺激的反应中以类似方式改变了放电频率。其余对PFC和有害刺激都有反应而改变放电频率的神经元，对这两种刺激的反应方式相反。对于后一种类型，发现当同时给予PFC和有害刺激时，PFC刺激消除了对有害刺激的反应。还观察到，微量离子电泳给予ME或NE经常（分别为100%和52%）模拟对PFC刺激的反应，从而表明这些神经递质可能参与介导PFC对中脑神经元的影响。
