Dynorphin B, also known as rimorphin, is a form of

dynorphin Dynorphins (Dyn) are a class of opioid peptides that arise from the precursor protein prodynorphin. When prodynorphin is cleaved during processing by proprotein convertase 2 (PC2), multiple active peptides are released: dynorphin A, dynorphin B, a ...

and an

endogenous Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell. In contrast, exogenous substances and processes are those that originate from outside of an organism. For example, es ...

opioid peptide Opioid peptides are peptides that bind to opioid receptors in the brain; opiates and opioids mimic the effect of these peptides. Such peptides may be produced by the body itself, for example endorphins. The effects of these peptides vary, but th ...

with the

amino acid sequence Protein primary structure is the linear sequence of amino acids in a peptide or protein. By convention, the primary structure of a protein is reported starting from the amino-terminal (N) end to the carboxyl-terminal (C) end. Protein biosynthes ...

Tyr-Gly-Gly-Phe-Leu-Arg-Arg-Gln-Phe-Lys-Val-Val-Thr. Dynorphin B is generated as a proteolytic cleavage product of

leumorphin Leumorphin, also known as dynorphin B1–29, is a naturally occurring endogenous opioid peptide. Derived as a proteolytic cleavage product of residues 226-254 of prodynorphin (preproenkephalin B), leumorphin is a nonacosapeptide (29 amino acid ...

, which in turn is a cleavage product of

preproenkephalin B Prodynorphin, also known as proenkephalin B, is an opioid polypeptide hormone involved with chemical signal transduction and cell communication. The gene for prodynorphin is expressed in the endometrium and the striatum, and its gene map locus is 20 ...

(prodynorphin). Dynorphin B has an identical N-terminal sequence, but different C-terminal sequence to

Dynorphin A Dynorphin A is a dynorphin, an endogenous opioid peptide with the amino acid sequence: Tyr-Gly-Gly-Phe-Leu-Arg-Arg-Ile-Arg-Pro-Lys-Leu-Lys. Dynorphin A1–8 is a truncated form of dynorphin A with the amino acid sequence: Tyr-Gly-Gly-Phe-Leu-Ar ...

. In an alanine scan of the non-glycine residues of dynorphin B, it was discovered that Tyr¹ and Phe⁴ residues are critical for both opioid receptor affinity and κ-opioid receptor agonist potency, Arg⁶ and Arg⁷ promote κ-opioid affinity and Lys¹⁰ contributes to the opioid receptor affinity.

Inducers of Dynorphin B

Cannabinoid CP55,940 and △⁹-tetrahydrocannabinol (△⁹-THC) can induce the release of dynorphin B, which in return acts as an

agonist An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...

of κ-opioid receptors, resulting in the production of antinociception. Similarly, Tyr-D-Arg-Phe-Sar (TAPS) is capable of promoting a release of dynorphin B through the simulation of μ₁-opioid receptors, causing a production of antinociception. The antinociceptive effect produced by dynorphin B allows for spinal analgesia.

References

Neuropeptides Kappa-opioid receptor agonists Opioid peptides {{biochem-stub

Inducers of Dynorphin B

See also

References