Increased gabaergic input to ventral tegmental area dopaminergic neurons associated with decreased cocaine reinforcement in μ-opioid receptor knockout mice

The reduced cocaine self-administration and increased GABAergic input to VTA dopaminergic neurons in μ-opioid receptor knockout mice supports the notion that suppression of GABAergic input onto dopaminergic neurons in the VTA contributes to μ-opioid receptor modulation of cocaine reinforcement.