Ramaekers A, Parmentier M L, Lasnier C, Bockaert J, Grau Y
UPR CNRS 9023, Mécanismes Moléculaires des Communications Cellulaires, CCIPE, 34094 Montpellier Cedex 5, France.
J Comp Neurol. 2001 Sep 17;438(2):213-25. doi: 10.1002/cne.1310.
L-glutamate is the excitatory neurotransmitter at neuromuscular junctions in insects. It may also be involved in neurotransmission within the central nervous system (CNS), but its function therein remains elusive. The roles of glutamatergic synapses in the Drosophila melanogaster CNS were investigated, with focus on the study of DmGluRA, a G-protein-coupled glutamate receptor. In a first attempt to determine the function of this receptor, we describe its distribution in the larval and adult Drosophila CNS, using a polyclonal antibody raised against the C-terminal sequence of the protein. DmGluRA is expressed in a reproducible pattern both in the larva and in the adult. In particular, DmGluRA can be found in the antennal lobes, the optic lobes, the central complex, and the median bundle in the adult CNS. However, DmGluRA-containing neurons represented only a small fraction of all CNS neurons. DmGluRA immunoreactivity was not detected at the larval neuromuscular junction nor in the body wall muscles. The correlations between DmGluRA distribution and previously described glutamate-like immunoreactivity patterns, as well as the implications of these observations concerning the possible functions of DmGluRA in the Drosophila CNS, are discussed.
L-谷氨酸是昆虫神经肌肉接头处的兴奋性神经递质。它也可能参与中枢神经系统（CNS）内的神经传递，但其在其中的功能仍不清楚。研究了果蝇中枢神经系统中谷氨酸能突触的作用，重点是对G蛋白偶联谷氨酸受体DmGluRA的研究。在首次尝试确定该受体的功能时，我们使用针对该蛋白C末端序列产生的多克隆抗体，描述了它在幼虫和成年果蝇中枢神经系统中的分布。DmGluRA在幼虫和成虫中均以可重复的模式表达。特别是，在成年中枢神经系统的触角叶、视叶、中央复合体和中束中可以发现DmGluRA。然而，含有DmGluRA的神经元仅占所有中枢神经系统神经元的一小部分。在幼虫神经肌肉接头处和体壁肌肉中未检测到DmGluRA免疫反应性。讨论了DmGluRA分布与先前描述的谷氨酸样免疫反应模式之间的相关性，以及这些观察结果对DmGluRA在果蝇中枢神经系统中可能功能的影响。
