Monoamine modulation of tonic GABAA inhibition.

In recent years, it has become evident that many neurotransmitters and endogenous ligands differentially modulate synaptic γ-aminobutyric acid type A receptors (sGABAARs) and extrasynaptic GABAAR (eGABAARs). In this mini-review, we will summarize the available evidence on the ability of the monoamines serotonin (5-HT), noradrenaline (NA), and, in particular, dopamine (DA) to alter the functional response of eGABAARs, thus either increasing or decreasing tonic GABAA inhibition. Although this field of research is still in its infancy, it has already been demonstrated that eGABAARs show a nucleus-selective and neuronal-type-selective regulation by monoamines in a way that differs from that of sGABAARs. Further work will undoubtedly advance our knowledge of the intricate talk between monoamines and eGABAAR and may ultimately provide new leads for the treatment of neurological and neuropsychiatric disorders, where alteration in GABAAR function is one of the underlying causes.