NPY and substance dependence: For example, NPY activation in the CeA has opposite effects to CRF.48 NPY blocks high compulsive-like alcohol administration, blocks the transition to excessive drinking with the development of dependence, and blocks the increase in γ-aminobutyric acid (GABA) release in the CeA that is produced by alcohol.49,50 The combination of decreases in reward neurotransmitter function and the recruitment of brain stress systems provides powerful motivation for reengaging in drug taking and drug seeking.