Cobo M, Ferrer J M, Mora F
Department of Physiology, Faculty of Medicine, University of Granada, Spain.
Behav Brain Res. 1989 Jan 1;31(3):257-65. doi: 10.1016/0166-4328(89)90007-7.
Effects of electrolytic and kainic acid lesions at several stereotaxic planes of the lateral cortico-cortical prefrontal efferent pathway on self-stimulation of the medial prefrontal cortex were investigated. Electrolytic bilateral lesion of the sulcal prefrontal cortex, the first terminal area of this pathway, produced no effects on self-stimulation of the medial prefrontal cortex. However, bilateral electrolytic lesion of this pathway at the rostral part of the external capsule produced a permanent abolition of self-stimulation of the medial prefrontal cortex. These effects seemed selective since operant behaviour to obtain water, similar to that performed for self-stimulation and used as a control, was not affected by the lesion except on the 1st, 3rd (P less than 0.01) and 5th (P less than 0.05) days postlesion. Interestingly, bilateral microinjections of kainic acid (10 nmol in 0.8 microliters) at the same stereotaxic planes of the external capsule where electrolytic lesion was produced, had no effects on self-stimulation. These results suggest that fibres-of-passage through the external capsule are responsible for the abolition of self-stimulation. Bilateral electrolytic lesion of the entorhinal cortex, one of the caudal terminal areas of this descending set of fibres, produced a short transient decrease of self-stimulation of the medial prefrontal cortex. These results are discussed on the basis that complex, rather than single circuits are involved in maintaining self-stimulation in this neocortical area.
研究了在外侧皮质-皮质前额叶传出通路的几个立体定位平面上进行电解损伤和注射 kainic 酸对内侧前额叶皮质自我刺激的影响。该通路的第一个终末区域，即沟回前额叶皮质的双侧电解损伤，对内侧前额叶皮质的自我刺激没有影响。然而，在外侧囊嘴侧部分对该通路进行双侧电解损伤，导致内侧前额叶皮质的自我刺激永久性消失。这些影响似乎具有选择性，因为与自我刺激行为类似且用作对照的获取水的操作性行为，除了在损伤后的第 1、3（P<0.01）和 5（P<0.05）天外，不受损伤影响。有趣的是，在产生电解损伤的外侧囊相同立体定位平面上双侧微量注射 kainic 酸（10 nmol 于 0.8 μl 中），对自我刺激没有影响。这些结果表明，通过外侧囊的传导纤维负责自我刺激的消除。内嗅皮质是这一下行纤维束的尾侧终末区域之一，其双侧电解损伤导致内侧前额叶皮质的自我刺激短暂性下降。基于在这个新皮质区域维持自我刺激涉及复杂而非单一回路的观点，对这些结果进行了讨论。
