Beta-endorphin (often simply called endorphin) is a peptide neurotransmitter and hormone and one of a class of substances known as “endogenous opioids.” Its best-understood effect is natural pain inhibition, but it is also hypothesized to be involved in a number of other functions ranging from regulation of the stress response to the processing of rewarding experiences. In this video, I discuss beta-endorphin and some of its proposed functions.

TRANSCRIPT:

Beta-endorphin is a peptide neurotransmitter and hormone found in the central and peripheral nervous systems. 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 rewarding experiences. 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 understood.

References:

Corder G, Castro DC, Bruchas MR, Scherrer G. Endogenous and Exogenous Opioids in Pain. Annu Rev Neurosci. 2018 Jul 8;41:453-473. doi: 10.1146/annurev-neuro-080317-061522. Epub 2018 May 31.

Dalayeun JF, Norès JM, Bergal S. Physiology of beta-endorphins. A close-up view and a review of the literature. Biomed Pharmacother. 1993;47(8):311-20.

Dinas PC, Koutedakis Y, Flouris AD. Effects of exercise and physical activity on depression. Ir J Med Sci. 2011 Jun;180(2):319-25. doi: 10.1007/s11845-010-0633-9. Epub 2010 Nov 14.

Roth-Deri I, Green-Sadan T, Yadid G. Beta-endorphin and drug-induced reward and reinforcement. Prog Neurobiol. 2008 Sep;86(1):1-21. doi: 10.1016/j.pneurobio.2008.06.003. Epub 2008 Jun 18.

Veening JG, Barendregt HP. The effects of beta-endorphin: state change modification. Fluids Barriers CNS. 2015 Jan 29;12:3. doi: 10.1186/2045-8118-12-3.
Video Rating: / 5