Antkiewicz-Michaluk L
Department of Biochemistry, Polish Academy of Sciences, Kraków.
Pol J Pharmacol. 1995 May-Jun;47(3):253-64.
Ion entry into neurons occurs either through receptor-operated channels (ROC) or voltage-operated channels (VOC). The function of ROC depends crucially on the action of agonists, antagonists or compounds modulating particular types of receptors (GABA A, NMDA, Ach N receptors). The function of VOC is closely connected with the activity of protein kinases and the processes of phosphorylation of membrane proteins (K+, Na+, Ca2+ channels). Gamma aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the vertebrate brain. The GABA A receptor is a oligomeric complex of multiple binding sites and chloride channel. This complex contains recognition sites for GABA, anxiolytics such as benzodiazepine, anxiogenic--beta-carboline, and convulsant such as picrotoxin. Chloride ion channel plays a crucial role in anxiogenic, anxiolytic and convulsant activities. Glutamic acid is the main endogenous neurotransmitter for N-methyl-D-aspartate (NMDA)-type excitatory amino acid receptor. NMDA receptors connected with Ca2+ channel, have multiple modulatory sites which are affected by a wide range of compounds. There are NMDA and competitive NMDA antagonists site, the glycine site, the phencyclidine (PCP) site and the binding site of Mg2+ ions in this receptor complex. Calcium entry through NMDA receptors may be important in the etiology of many psychiatric disorders. VOC mediate rapid, voltage-gated changes in ion permeability during action potentials in neurons. Electrophysiological studies indicate the existence of three types of VOC (K+, Na+, Ca2+ channels). In number of neurons various subtypes of Ca2+ channels (P, T, N and L-type) occur together. Among them, the L-type calcium channel has been first described and most thoroughly studied. The L-type calcium channel is localized on nerve terminals in the pre and postsynaptic parts, as well as on cell bodies and may be involved in the mechanism of action of psychotropic drugs. Chronic treatment with various psychotropic drugs changes the density of voltage-dependent Ca2+ channels in the central nervous system. Thus calcium entry through both VOC and ROC may be important in the etiology of many psychiatric disorders.
离子进入神经元可通过受体操纵通道（ROC）或电压操纵通道（VOC）实现。ROC的功能关键取决于激动剂、拮抗剂或调节特定类型受体（GABAA、NMDA、乙酰胆碱N受体）的化合物的作用。VOC的功能与蛋白激酶的活性以及膜蛋白（钾离子、钠离子、钙离子通道）的磷酸化过程密切相关。γ-氨基丁酸（GABA）是脊椎动物大脑中的主要抑制性神经递质。GABAA受体是一个具有多个结合位点和氯离子通道的寡聚复合物。该复合物包含GABA、苯二氮䓬类抗焦虑药、β-咔啉类致焦虑剂以及印防己毒素等惊厥剂的识别位点。氯离子通道在致焦虑、抗焦虑和惊厥活动中起关键作用。谷氨酸是N-甲基-D-天冬氨酸（NMDA）型兴奋性氨基酸受体的主要内源性神经递质。与钙离子通道相连的NMDA受体有多个调节位点，受到多种化合物的影响。该受体复合物中有NMDA和竞争性NMDA拮抗剂位点、甘氨酸位点、苯环利定（PCP）位点以及镁离子结合位点。通过NMDA受体进入的钙离子可能在许多精神疾病的病因中起重要作用。VOC在神经元动作电位期间介导离子通透性的快速、电压门控变化。电生理研究表明存在三种类型的VOC（钾离子、钠离子、钙离子通道）。在许多神经元中，多种亚型的钙离子通道（P型、T型、N型和L型）共同存在。其中，L型钙通道最早被描述且研究最为深入。L型钙通道定位于突触前和突触后部分的神经末梢以及细胞体上，可能参与精神药物的作用机制。长期使用各种精神药物会改变中枢神经系统中电压依赖性钙离子通道的密度。因此，通过VOC和ROC进入的钙离子可能在许多精神疾病的病因中起重要作用。
