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enkephalin

[en-kef-uh-lin]
noun Biochemistry.
  1. either of two pentapeptides that bind to morphine receptors in the central nervous system and have opioid properties of relatively short duration; one pentapeptide (Met enkephalin) has the amino acid sequence Tyr-Gly-Gly-Phe-Met and the other (Leu enkephalin) has the sequence Tyr-Gly-Gly-Phe-Leu.

Origin of enkephalin

1970–75; < Greek enképhal(os) encephalon + -in2
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for enkephalin

enkephalin

encephalin (ɛnˈsɛfəlɪn)

noun
  1. a chemical occurring in the brain, having effects similar to those of morphineSee also endorphin
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
enkephalin in Medicine

enkephalin

[ĕn-kĕf′ə-lĭn]
n.
  1. Either of two closely related pentapeptides having opiate qualities and occurring especially in the brain and spinal cord.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.