Extracellular signal-regulated protein kinase-2 signaling in the nucleus accumbens facilitates stress-susceptibility and cocaine reinstatement.

Second messenger signaling within the mesolimbic reward circuit plays a key role in the negative effects of stress and the underlying mechanisms that promote drug abuse. Since the nucleus accumbens (NAc) integrates reward valence, we investigated how extracellular signal-regulated protein kinase-2 (ERK2) signaling affects the development of stress-related comorbidities, including negative affect and drug sensitivity.