Leu-enkephalin explained

Leu-enkephalin is an endogenous opioid peptide neurotransmitter with the amino acid sequence Tyr-Gly-Gly-Phe-Leu that is found naturally in the brains of many animals, including humans.^{[1] [2]} It is one of the two forms of enkephalin; the other is met-enkephalin. The tyrosine residue at position 1 is thought to be analogous to the 3-hydroxyl group on morphine.^[3] Leu-enkephalin has agonistic actions at both the μ- and δ-opioid receptors, with significantly greater preference for the latter. It has little to no effect on the κ-opioid receptor.^{[4] [5]}

See also

• Met-enkephalin

Notes and References

1. Lazarus LH, Ling N, Guillemin R . beta-Lipotropin as a prohormone for the morphinomimetic peptides endorphins and enkephalins . Proceedings of the National Academy of Sciences of the United States of America . 73 . 6 . 2156–9 . June 1976 . 1064883 . 430469 . 10.1073/pnas.73.6.2156. 1976PNAS...73.2156L . free .
2. Hughes J, Kosterlitz HW, Smith TW . The distribution of methionine-enkephalin and leucine-enkephalin in the brain and peripheral tissues. 1977 . British Journal of Pharmacology . 120 . 4 Suppl . 428–36; discussion 426–7 . February 1997 . 9142421 . 3224324 . 10.1111/j.1476-5381.1997.tb06829.x.
3. Schiller PW, Yam CF, Lis M . Evidence for topographical analogy between methionine-enkephalin and morphine derivatives . Biochemistry . 16 . 9 . 1831–8 . May 1977 . 870028 . 10.1021/bi00628a011.
4. Porreca F, Mosberg HI, Hurst R, Hruby VJ, Burks TF . Roles of mu, delta and kappa opioid receptors in spinal and supraspinal mediation of gastrointestinal transit effects and hot-plate analgesia in the mouse . The Journal of Pharmacology and Experimental Therapeutics . 230 . 2 . 341–8 . August 1984 . 6086883 .
5. Raynor K, Kong H, Chen Y, Yasuda K, Yu L, Bell GI, Reisine T . Pharmacological characterization of the cloned kappa-, delta-, and mu-opioid receptors . Molecular Pharmacology . 45 . 2 . 330–4 . February 1994 . 8114680 .