Astrocytes are a heterogeneous population of neural cells with diverse structural, functional and molecular characteristics responsible for homeostasis and protection of the central nervous system (CNS). Unlike neurones, astrocytes do not generate action potentials, but employ fluctuations of cytosolic ions as a substrate for their excitability. Ionic signals are associated with neuronal activity and these signals initiate an array of responses ranging from the activation of plasmalemmal homeostatic transporters to the secretion of numerous signalling molecules including neuromodulators, neurotransmitter precursors, metabolic substrates, trophic factors and cytokines. Thus, astrocytes regulate the synaptic connectivity of the neuronal networks by supporting neurotransmitter metabolism, synaptogenesis, synaptic elimination and the synaptic plasticity that contributes to cognitive processing including learning, memory, emotionality and behaviour. Astroglia-specific regulatory pathways affect the most fundamental properties of neuronal networks from their excitability to synaptic connectivity. Thus, it is the concerted action of glia and neurones, which, through distinct mechanisms, produce the behavioural outputs of the ultimate control centre that we call the brain.

星形胶质细胞是具有不同结构，功能和分子特征的神经细胞的异质群体，负责稳态和中枢神经系统（CNS）的保护。与神经元不同，星形胶质细胞不产生动作电位，而是利用胞质离子的波动作为其兴奋性的底物。离子信号与神经元活动有关，这些信号引发一系列反应，范围从质膜稳态转运蛋白的激活到许多信号分子的分泌，包括神经调节剂，神经递质前体，代谢底物，营养因子和细胞因子。因此，星形胶质细胞通过支持神经递质的代谢，突触形成，调节神经元网络的突触连通性，突触消除和突触可塑性有助于认知过程，包括学习，记忆，情感和行为。从神经元的兴奋性到突触连接性，特定于星形胶质细胞的调节途径会影响神经元网络的最基本特性。因此，正是神经胶质和神经元的协同作用，通过不同的机制，产生了我们称为大脑的最终控制中心的行为输出。