endogenous opioid

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endogenous opioid

an opiate-like substance, such as an endorphin, produced by the body.


1. any synthetic narcotic that has opiate-like activities but is not derived from opium.
2. denoting naturally occurring peptides, e.g. enkephalins, that exert opiate-like effects by interacting with opiate receptors of cell membranes.

endogenous opioid
opioid receptors
specific receptor sites for opioids, named for the drugs which have a high binding affinity for them. The main ones are mu (morphine), kappa (opioid agonist-antagonists such as pentazocine) and delta (enkephalin endogenous opioids). Subtypes exist and others, such as sigma and epsilon, have been identified.
References in periodicals archive ?
Endogenous opioids were reported to be negatively correlated with oxytocin (Bicknell and Leng, 1982; Douglas et al.
Endogenous opioid peptides and the control of the menstrual cycle.
1] receptor coupling inhibits the endogenous opioid system by decreasing the sensitivity of both [mu] and [kappa] opioid receptors (Mackie 2008).
Orgasm can act on migraine headache by endogenous opioid secretion and opioid receptor agonism occurring in initial migraine generator phase.
Opioid drugs act via naturally occurring receptors in the body that normally respond to endogenous opioid neurotransmitters.
Furthermore, there is evidence of an interaction between endogenous opioid peptides and the dopaminergic mesocorticolimbic system in behavioral responses to stress.
A team led by Jon-Kar Zubieta of the University of Michigan aimed to measure the impact on two chemical messenger systems in the brain--the endogenous opioid and dopamine systems--when pain was induced and a placebo "treatment" was administered at regular intervals.
Prior studies have suggested that one possible mechanism for tanning dependence is endogenous opioid release during ultraviolet radiation (UVR) exposure: Blinded study participants demonstrated a preference for UVR vs.
These findings suggest that whereas stress-induced relapse may involve the CRF system, alcohol cue-induced relapse may be mediated by the endogenous opioid system.
Induction of human mast cell degranulation by opiates and endogenous opioid peptides: evidence for opiate and non-opiate receptor participation.
The study found major differences between women with serious depression and healthy women in a brain-chemical system that's crucial to stress and emotions, the endogenous opioid system.