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endogenous opioid

a substance produced in the body that has the analgesic and euphoric effects of morphine. Three families of endogenous opioids are well known: the enkephalins, endorphins, and dynorphins. All are neuropeptides that bind to opioid receptors in the central nervous system; they are mostly inhibitory, acting like opiates to block pain. They bind relatively nonselectively to opioid receptors, although enkephalins bind preferentially to the delta opioid receptors and dynorphins to kappa opioid receptors. Three other endogenous opioid peptides have been identified: nociceptin/orphanin FQ (N/OFQ) and endomorphins 1 and 2. Also called opioid neurotransmitter.

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Psychology term of the day

December 18th 2024

homeostasis

homeostasis

n.

1. the regulation by an organism of all aspects of its internal environment, including body temperature, salt–water balance (see osmoregulation), acid–base balance (see hydrogen-ion concentration), and blood sugar level. This involves monitoring changes in the external and internal environments by means of receptors and adjusting bodily processes accordingly. Compare tension law. [first described by Walter B. Cannon]

2. maintenance of a stable balance, evenness, or symmetry. —homeostatic adj.