Beta-endorphin is a peptide neurotransmitter and hormone found in the central and peripheral
It is one of a class of substances called endogenous opioids, which received their name
because they are produced by the body and bind to the same receptors that opioid drugs
like morphine bind to.
The term endorphin is a blend of the words “endogenous” and “morphine.”
By binding to opioid receptors, beta-endorphin can elicit natural pain-relieving effects
that have been found to be more potent than morphine.
Beta-endorphin may achieve this type of analgesia by binding to opioid receptors in various
regions of the nervous system.
It can, for example, bind to opioid receptors in the spinal cord and inhibit the activation
of neurons that transmit pain signals to the brain.
And, beta-endorphin can act on opioid receptors in the brainstem that prompt the inhibition
of pain signaling in the spinal cord through descending pathways.
Pain inhibition is the best-understood effect of beta-endorphin, but the peptide has also
been linked to a long list of other functions.
For example, beta-endorphin is released during stress and is thought to play a role in regulating
the stress response as well as in the pain inhibition that can occur during acute stress.
Beta-endorphin is also thought to interact with the dopamine system and be involved with
Some research suggests beta-endorphin plays a role in the positive effects exercise can
have on mood.
And it has been associated with food intake and sexual behavior.
Links between beta-endorphin and positive mood have led to a number of claims about
endorphins promoting pleasure and happiness.
In truth, however, much still needs to be learned about the functions of beta-endorphin
in the nervous system and the role of beta-endorphin in positive mood states is still not fully