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endorphin

American  
[en-dawr-fin] / ɛnˈdɔr fɪn /

noun

  1. any of a group of peptides occurring in the brain and other tissues of vertebrates, and resembling opiates, that react with the brain's opiate receptors to raise the pain threshold.


endorphin British  
/ ɛnˈdɔːfɪn /

noun

  1. any of a class of polypeptides, including enkephalin, occurring naturally in the brain, that bind to pain receptors and so block pain sensation

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

endorphin Scientific  
/ ĕn-dôrfĭn /
  1. Any of a group of peptide substances secreted by the anterior portion of the pituitary gland that inhibit the perception of painful stimuli. Endorphins act as neurotransmitters in the pain pathways of the brain and spinal cord. Narcotic drugs may stimulate the secretion of endorphins.


Closer Look

Endorphins are long chains of amino acids, or polypeptides, that are able to bind to the neuroreceptors in the brain and are capable of relieving pain in a manner similar to that of morphine. There are three major types of endorphins: beta-endorphins are found almost entirely in the pituitary gland, while enkephalins and dynorphins are both distributed throughout the nervous system. Scientists had suspected that analgesic opiates, such as morphine and heroin, worked effectively against pain because the body had receptors that were activated by such drugs. They reasoned that these receptors probably existed because the body itself had natural painkilling compounds that also bonded to those receptors. When scientists in the 1970s isolated a biochemical from a pituitary gland hormone that showed analgesic properties, Choh Li, a chemist from Berkeley, California, named it endorphin, meaning “the morphine within.” Besides behaving as a pain reducer, endorphins are also thought to be connected to euphoric feelings, appetite modulation, and the release of sex hormones. Prolonged, continuous exercise contributes to an increased production of endorphins and, in some people, the subsequent “runner's high.”

Etymology

Origin of endorphin

1970–75; end(ogenous) (m)orphine, with -ine respelled as -in 2

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"The people you talk to, and laugh with, it leads to enhanced levels of endorphin uptake," says Prof Scott.

From BBC

I tend toward depression and anxiety, so dancing is an easy way to immediately get your endorphins and it doesn’t feel like as much of a demand as going for a jog.

From Los Angeles Times

For Bruckner, rising melodic scales, humongous fanfares with trumpets and horns and Wagner tubas galore and repeated patterns over and over by an unstoppable orchestra serve as injections of musical endorphins.

From Los Angeles Times

"It's something about sweating, being uncomfortable and the endorphins it releases."

From BBC

The neurochemicals involved in this process are different than those mediating habit formation and include a chemical messenger called noradrenaline and internally produced opioids such as endorphins.

From Salon