Kiser R S, Lebovitz R M
Physiol Behav. 1975 Jul;15(1):47-53. doi: 10.1016/0031-9384(75)90278-4.
In these experiments we have examined the role of brain monoamines in the fearlike aversive responses produced by the electrical stimulation of the dorsal midbrain tegmentum (DMT). Chronic bipolar stimulating electrodes were bilaterally implanted into the DMT of 77 rats. Electrical stimulation via 34 of these electrodes produced fearlike, escape seeking responses. These animals were then trained for stable stimulus escape using a decremental bar pressing paradigm. In this paradigm, each bar press reduced the stimulation current by a predetermined fraction (5 percent) of the initial current level. Perceived aversive strength of the initial stimulus current was thereby represented by an increasing function of the number of bar presses to escape. Administration of the catecholamine depleting drug alpha-methyl-para-tyrosine yielded no change in bar pressing relative to saline-injected controls. However, the serotonin depleting drub para-chlorophenylalanine produced a marked increase in decremental bar pressing compared to saline-injected controls. These results suggest that fearlike responses to DMT stimulation may be dependent upon brain serotonin levels and relatively insensitive to levels of brain catecholamines.
在这些实验中，我们研究了脑单胺类物质在电刺激中脑背侧被盖区（DMT）所产生的类似恐惧的厌恶反应中的作用。将慢性双极刺激电极双侧植入77只大鼠的DMT。通过其中34个电极进行电刺激产生了类似恐惧的逃避反应。然后使用递减压杆范式对这些动物进行稳定刺激逃避训练。在该范式中，每次压杆会使刺激电流降低初始电流水平的预定比例（5%）。因此，初始刺激电流的感知厌恶强度由逃避所需的压杆次数的增加函数表示。给予儿茶酚胺耗竭药物α-甲基-对-酪氨酸后，与注射生理盐水的对照组相比，压杆行为没有变化。然而，与注射生理盐水的对照组相比，血清素耗竭药物对氯苯丙氨酸导致递减压杆行为显著增加。这些结果表明，对DMT刺激的类似恐惧反应可能依赖于脑血清素水平，而对脑儿茶酚胺水平相对不敏感。
