An opioidergic agent, is a chemical which functions to directly modulate the opioid neuropeptide systems (i.e., endorphin, enkephalin, dynorphin, nociceptin) in the body or brain.
This release of dopamine induced by nicotine is thought to occur via a cholinergicdopaminergic link, mediated by a neuropeptide, ghrelin, in the ventral tegmentum.
Immunological, physiological and psychological stressors engage cytokines and other immune molecules as mediators of interactions with neuroendocrine, neuropeptide, and neurotransmitter systems.