dynorphin

Dynorphin is a class of peptides produced by many different populations of neurons, which has some opiate-like activity. It is thus classed as an endogenous opioid peptide. Dynorphin functions primarily as a kappa opioid receptor agonist, meaning that it acts mainly at kappa opioid receptors. Other opioid peptides include beta-endorphin, met-enkephalin, leu-enkephalin and endomorphins. The dynorphins, which include dynorphin A, dynorphin B, alpha- and beta-neoendorphin, and big dynorphin, are all the products of a single gene, 'preprodynorphin'.
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Dynorphin /dy·nor·phin/ any of a family of opioid peptides found throughout the central and peripheral nervous systems; most are agonists at opioid [more]Dynorphin - Community and Resources