Astrocytic l-Lactate Signaling Facilitates Amygdala-Anterior Cingulate Cortex Synchrony and Decision Making in Rats

Human brain imaging studies have revealed the anterior cingulate cortex (ACC) as a key brain region for mediating visceral-pain-cognitive interactions. Recently, we characterized impairments of long-term potentiation and spike-field coherence in the basolateral amygdala (BLA)-ACC network in association with a decision-making deficit in rats with visceral hypersensitivity (VH). Now, by combining integrative neurobiological approaches, we show that ACC-reactive astrogliosis and activity-dependent impairment of lactate release occur in VH rats. Exogenous lactate supply rescues chronic-visceral-pain-caused impairments of ACC phase locking and decision making, which can be mimicked by optogenetic activation of ACC astrocytes. Large-scale electrophysiological recordings in free-moving animals during a decision-making task indicate that optogenetic astrocytic activation improves decision-making performance and engages ACC phase locking and BLA-to-ACC information flow. Collectively, these observations support the idea of an "astrocyte-neuron l-lactate shuttle" and suggest that targeting astrocytes may help with cognitive dysfunctions under chronic visceral pain.