Fast-Acting Sublingual Zolpidem for Middle-of-the-Night Wakefulness

Figure 2

The pentameric structure of the GABA_A receptor is composed of 4-transmembrane monomeric subunits (a disulfide bond in the N-terminal extracellular domain, characteristic of the family of cys-loop receptors which includes the GABA_A receptor, is depicted). Zolpidem allosterically enhances Cl⁻ influx, which hyperpolarizes the neuronal transmembrane potential (at I), thereby making it less likely to fire in response to excitatory input (at E).