Neuroactive steroids (widely known as neurosteroids), including progesterone and several of its metabolites, have been shown to mediate some of their physiological effects though a modulatory site on GABAA receptors. Epiallopregnanolone is a metabolite of progesterone and a 3β-isomer of allopregnanolone , which has been shown to enhance GABA neurotransmission. Epiallopregnanolone is inactive as a GABAA receptor modulator and is used as a control substance to examine GABA neurotransmission.
