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Neoendorphins are a group of endogenous opioid peptides derived from the proteolytic cleavage of prodynorphin. They include α-neoendorphin and β-neoendorphin. The α-neoendorphin is present in greater amounts in the brain than β-neoendorphin. Both are products of the dynorphin gene, which also expresses dynorphin A, dynorphin A-(1-8), and dynorphin B. These opioid neurotransmitters are especially active in Central Nervous System receptors, whose primary function is pain sensation. These peptides all have the consensus amino acid sequence of Try-Gly-Gly-Phe-Met (met-enkephalin) or Tyr-Gly-Gly-Phe-Leu ( leu-enkephalin). Binding of neoendorphins to opioid receptors (OPR), in the dorsal root ganglion (DRG) neurons results in the reduction of time of calcium-dependent action potential. The α-neoendorphins bind OPRD1(delta), OPRK1(kappa), and OPRM1 (mu) and β-neoendorphin bind OPRK1.
References
- ↑ Charles Chavkin; William J Shoemaker; Jacquiline F. McGinti; Alejandro Bayon; Floyd E. Bloom (March 1985). "Characterization of the Prodynorphin and Proenkephalin Neuropeptide Systems in Rat Hippocampus" (PDF). Journal of Neuroscience. 5 (3): 806–816. doi: 10.1523/jneurosci.05-03-00808.1985 . PMC 6565022 . PMID 3838345.
- ↑ Alberto Pérez-Rosado; María Gómez; Jorge Manzanares; José A. Ramos; Javier Fernándezruiz (2002). "Changes in prodynorphin and POMC gene expression in several brain regions of rat fetuses prenatally exposed to Δ-tetrahydrocannabinol". Neurotoxicity Research. 4 (3): 211–218. doi:10.1080/10298420290023936. PMID 12829401. S2CID 25878244.
- ↑ Chang-wang Wang; Min Ma; Wei-guang Lu; Ru-qin Luo (11 September 2019). "Association between prodynorphin gene polymorphisms and opioid dependence susceptibility: a meta-analysis". BMC Psychiatry. 19 (281). doi: 10.1186/s12888-019-2272-7 . PMID 31510971. S2CID 202550535.