Figure 1.

An astrocyte’s resting membrane potential (RMP) is likely influenced by multiple extrinsic and intrinsic factors including (A) ion channel subtype expression and density, particularly Ca²⁺, Na⁺, and K⁺ channels (ions represented by green, red, and blue circles, respectively); (B) astrocyte morphology; (C) neighboring cells including neurons, oligodendrocytes, microglia, and other astrocytes through the release of neurotransmitters, gliotransmitters, and other factors; (D) intracellular astrocyte signaling cascades such as the cAMP pathway. cAMP PKA-dependent and PKA-independent mechanisms have been proposed to influence astrocyte RMP (Bolton et al., 2006).