Electroacupuncture at low frequencies mainly releases enkephalins and endorphins and at high frequencies, primarily dynorphins
 Other placental hormones include corticotropin-releasing hormone, endorphins, dynorphins
, gonadotropin-releasing hormones, inhibin, leptin, prolactin, and prorenin.
Other endogenous opioids include endorphin, formed after the cleavage of the precursor proopiomelanocortin (POMC) protein, and dynorphins
derived from cleavage of prodynorphin.
And the dynorphins
interact selectively with the kappa opioid receptor (Gianoulakis, 1993).
Opioid receptors are activated by peptide neurotransmitters (endorphins, dynorphins
and enkephalins) in the brain and also by plant-derived and synthetic drugs mimicking these peptides: among them morphine, codeine, oxycodone and heroin.
Opioid peptides include the endorphins, enkephalins, and dynorphins
. Enkephalins are frequently found in presynaptic (axoaxonic) synapses.
There are endogenous opioids including endorphins, endomorphins, enkephalins, dynorphins
, and nociceptin.
Opioid receptors can be found within the central nervous system (CNS) as well as throughout the peripheral tissues, and they are normally stimulated by endogenous peptides (endorphins, enkephalins, and dynorphins
) produced in response to noxious stimulation.
are opioid peptides that derive from the prodynorphin precursor and are the presumed endogenous ligands for the [kappa] opioid receptor (Chavkin et al., 1982).
The topics include neuropeptide biosynthesis, dynorphins
in central nervous system pathology, the influence of anabolic androgenic steroids on dynorphinergic pathways in the rat's brain, angiotensin II receptors and neuroprotection, and classic and nonclassic cases of interactions between opioid ligands and their receptors.
Biogenesis, release and interaction of enkephalins and dynorphins
. Brit Med Bull 1983; 39:17-24.
are a class of endogenous opioids that interact with the -opioid receptor and are thought to mediate negative emotional states.