Definition of "enkephalin" [enkephalin]

• Either of two closely related pentapeptides having opiate qualities and occurring in the brain, spinal cord, and other parts of the body. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The principal objection came from Hughes and Kosterlitz, who preferred the term enkephalin."
• "Although the effects of alcohol and TIQs on the brain appear to be similar to that of enkephalin, that is, they activate opiate receptors, it is probable that other neurotransmitters and other receptors are involved as well."
• "The activating enzymes are members of a class called enkephalin convertase."