This paper is the thirty-seventh consecutive installment of the annual review of research
concerning the endogenous opioid system. It summarizes papers published during 2014 …

The melanocortin system of the hypothalamus, including the neuropeptides α-melanocyte
stimulating hormone (αMSH) and agouti-related protein (AgRP), and their receptors, the …

Suppression of dangerous or inappropriate reward-motivated behaviors is critical for
survival, whereas therapeutic or recreational opioid use can unleash detrimental behavioral …

Opioid neuropeptides and their receptors are evolutionarily conserved neuromodulatory
systems that profoundly influence behavior. In dorsal striatum, which expresses the …

Presynaptic cannabinoid-1 receptors (CB1-R) bind endogenous and exogenous
cannabinoids to modulate neurotransmitter release. CB1-Rs are expressed throughout the …

The central melanocortin (MC) system mediates its effects on food intake via MC3 (MC3R)
and MC4 receptors (MC4R). Although the role of MC4R in meal size determination …

Food intake, which is a highly reinforcing behavior, provides nutrients required for survival in
all animals. However, when fat and sugar consumption goes beyond the daily needs, it can …

Disturbances in the function of the mesostriatal dopamine system may contribute to the
development and maintenance of chronic pain, including its sensory and …

Modulation of corticostriatal plasticity alters the information flow throughout basal ganglia
circuits and represents a fundamental mechanism for motor learning, action selection, and …

Abstract μ-Opioid receptors (MORs) are densely expressed in different brain regions known
to mediate reward. One such region is the striatum where MORs are densely expressed, yet …