Dynorphin A inhibits nociceptin-converting enzyme from the rat spinal cord.
Cysteine proteinase found in the spinal cord of rat, called nociceptin-converting enzyme (NCE), is competitively inhibited by dynorphin A and its fragment des-[Tyr(1)]-DYN A. This proteinase converts orphanin FQ/nociceptin (OFQ/N) to two major fragments: OFQ/N(1-11) and further OFQ/N(1-6) with analgesic properties. Dynorphin A at the concentration of 10 microM increases K(M) from 15.0 to 55.9 microM. The calculated K(i) for this interaction was estimated at 3.7 microM. This observation may suggest an interaction between opioid and nociceptive systems which may be affected by the balance between opioid and antiopioid systems. This balance between particular OFQ/N sequences that are derived from the same precursor and regulated by proteinases may play an important role in pain. Interestingly, dynorphin B does not reveal a similar action on the NCE.
Suder
P
P
Faculty of Chemistry and Regional Laboratory, Jagiellonian University, Ingardena Street 3, PL-30-060 Krakow, Poland.
Wade
D
D
Łegowska
A
A
Kotlińska
J
J
Rolka
K
K
Silberring
J
J
D000595:Amino Acid Sequence; D000818:Animals; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D004399:Dynorphins / Q000494:pharmacology*; D007700:Kinetics; D008297:Male; D008969:Molecular Sequence Data; D018847:Opioid Peptides / Q000737:chemistry / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013116:Spinal Cord / Q000201:enzymology*; D014665:Vasodilator Agents / Q000737:chemistry / Q000378:metabolism; D000097629:Nociceptin
D003546:Cysteine Endopeptidases; D004399:Dynorphins; D018847:Opioid Peptides; D010446:Peptide Fragments; D014665:Vasodilator Agents; D000097629:Nociceptin