Maxwell R C, Fink G
MRC Brain Metabolism Unit, University Department of Pharmacology, Edinburgh, U.K.
Neuroscience. 1988 Jan;24(1):241-63. doi: 10.1016/0306-4522(88)90328-4.
The aim of this study was to investigate the pattern of [14C]2-deoxyglucose uptake in anaesthetized rat brain produced by electrical stimulation of brain areas implicated, by previous electrical stimulation studies, in the neural control of pituitary hormone and especially gonadotrophin secretion. Stimulation of the median eminence led to a significant increase in the relative metabolic activities of the arcuate, ventromedial hypothalamic, supraoptic and paraventricular nuclei and the preoptic area. Stimulation of the suprachiasmatic or paraventricular nuclei or the medial preoptic area, anterior hypothalamic area, the dorsal or ventral hippocampus or amygdala led to an increase in the relative metabolic activity of many brain regions known to have direct connections with these areas, but in addition produced increases in the relative metabolic activity of areas which have secondary connections. Hippocampal stimulation confirmed previous neuroanatomical findings of major intrinsic functional connections between different fields of the ipsilateral and contralateral hippocampus. Stimulation of the amygdala, unexpectedly, did not change the relative metabolic activity of the arcuate nucleus and medial preoptic area which have neuroanatomical connections with the amygdala. Similarly, stimulation of the medial preoptic area did not change significantly the relative metabolic activity of the mamillary body and dorsomedial thalamic area. The effect of preoptic area stimulation on the relative metabolic activity of several brain regions was changed by ovariectomy and by injection of oestradiol benzoate. Stimulation of the preoptic area and suprachiasmatic nuclei, but not the anterior hypothalamic area or other brain regions, increased significantly the plasma concentrations of luteinizing hormone. These results show that (i) electrical stimulation of brain areas concerned with the control of gonadotrophin and other pituitary hormone secretion changes the metabolic activity of nuclei and neural pathways extrinsic as well as intrinsic to the hypothalamic-pituitary system, (ii) the [14C]2-deoxyglucose method can detect changes in antidromic as well as orthodromic activity and in multi-synaptic pathways, (iii) neuroanatomical pathways are not always activated metabolically by electrical stimulation, and (iv) the preoptic-suprachiasmatic nucleus gonadotrophin control system is discrete and is little affected by increased metabolic activity of the hypothalamus produced by stimulation of the anterior hypothalamic area or other brain areas.
本研究的目的是通过电刺激先前电刺激研究中涉及垂体激素尤其是促性腺激素分泌神经控制的脑区，来研究麻醉大鼠脑中[14C]2-脱氧葡萄糖的摄取模式。刺激正中隆起导致弓状核、腹内侧下丘脑核、视上核、室旁核和视前区的相对代谢活性显著增加。刺激视交叉上核或室旁核、内侧视前区、下丘脑前区、背侧或腹侧海马体或杏仁核，会导致许多已知与这些区域有直接联系的脑区的相对代谢活性增加，但此外还会使具有二级联系的区域的相对代谢活性增加。海马体刺激证实了先前神经解剖学研究中关于同侧和对侧海马体不同区域之间主要内在功能联系的发现。出乎意料的是，刺激杏仁核并未改变与杏仁核有神经解剖学联系的弓状核和内侧视前区的相对代谢活性。同样，刺激内侧视前区也未显著改变乳头体和背内侧丘脑区的相对代谢活性。视前区刺激对几个脑区相对代谢活性的影响会因卵巢切除术和注射苯甲酸雌二醇而改变。刺激视前区和视交叉上核，但不包括下丘脑前区或其他脑区，会显著提高黄体生成素的血浆浓度。这些结果表明：（i）电刺激与促性腺激素和其他垂体激素分泌控制有关的脑区会改变下丘脑-垂体系统内外的核团和神经通路的代谢活性；（ii）[14C]2-脱氧葡萄糖法可以检测逆行和顺行活动以及多突触通路中的变化；（iii）神经解剖学通路并不总是因电刺激而在代谢上被激活；（iv）视前-视交叉上核促性腺激素控制系统是离散的，并且受下丘脑前区或其他脑区刺激所产生的下丘脑代谢活性增加的影响很小。
