Karádi Z, Faludi B, Hernádi I, Lénárd L
Hungarian Academy of Sciences, Pécs University, Medical School, Hungary.
Neurobiology (Bp). 1995;3(3-4):241-56.
Our parallel investigations in the lateral hypothalamic are (LHA), amygdaloid body (AMY) and globus pallidus (GP) provided evidence for the existence of glucose-sensitive (GS) neurons in these forebrain regions. To examine exogenous chemosensory responsiveness of these cells, extracellular single neuron activity was recorded in anesthetized or alert rhesus monkeys and in anesthetized rats during 1) microelectrophoretic administration of chemicals and 2) gustatory and 3) olfactory stimulations. The GS cells in all three forebrain structures were more likely than the glucose-insensitive (GIS) neurons to change in firing rate in response to tastes and smells. The gustatory (and olfactory) GS neurons, compared to the non-gustatory GS or both types of GIS cells, displayed significantly higher sensitivities to catecholamines. Neurons with both "endogenous" and "exogenous" chemosensitivity were found to be topographically organized in the LHA, AMY and GP as well. While receiving further evidence for the substantial morphological and functional overlapping of the brain's glucose-monitoring neural network and the central gustatory representations, on the basis of the present and previous findings, it is suggested that constituents of this complex system accomplish a simultaneous monitoring, integration and control of a broad variety of feeding-associated signals of the internal and external milieux for the biological welfare of the organism.
我们对下丘脑外侧区（LHA）、杏仁体（AMY）和苍白球（GP）进行的平行研究为这些前脑区域存在葡萄糖敏感（GS）神经元提供了证据。为了检测这些细胞对外源化学感觉的反应性，在麻醉或清醒的恒河猴以及麻醉的大鼠中记录细胞外单神经元活动，记录过程如下：1）通过微电泳给药化学物质；2）进行味觉刺激；3）进行嗅觉刺激。与葡萄糖不敏感（GIS）神经元相比，所有这三个前脑结构中的GS细胞对味觉和嗅觉反应时更有可能改变放电频率。与非味觉GS神经元或两种类型的GIS细胞相比，味觉（和嗅觉）GS神经元对儿茶酚胺表现出明显更高的敏感性。同时具有“内源性”和“外源性”化学敏感性的神经元在LHA、AMY和GP中也呈拓扑分布。基于目前和先前的研究结果，虽然进一步证明了大脑葡萄糖监测神经网络与中枢味觉表征在形态和功能上存在大量重叠，但仍表明这个复杂系统的组成部分会同时监测、整合和控制来自内部和外部环境的各种与进食相关的信号，以保障机体的生物福利。
