Opioid peptides are potent analgesics with therapeutic potential in the treatment of acute
and chronic pain. Their efficacy is limited by peptidases (enkephalinases). Opiorphin …

Human opiorphin QRFSR-peptide protects enkephalins from degradation by human neutral
endopeptidase (hNEP) and aminopeptidase-N (hAP-N) and inhibits pain perception in a …

Background: Opiorphin is an endogenous human peptide regulator of enkephalin
bioavailability. It inhibits enkephalin-inactivating ectopeptidases to produce analgesia and …

Like other endogenous enkephalinase inhibitors, human opiorphin peptide (QRFSR)
attenuates catabolism of enkephalins and appears to be a promising therapeutic, displaying …

Human opiorphin (Gln-Arg-Phe-Ser-Arg; QRFSR-peptide) is a physiological inhibitor of
enkephalin-inactivating peptidases. We previously demonstrated that opiorphin can …

Background Opiorphin is a naturally occurring potent analgesic human peptide. It protects
enkephalins from degradation and inhibits pain perception in various acute pain models via …

Background: Opiorphin has been reported to show a stronger analgesic effect than
morphine without causing side effects brought about by morphine-like drugs. Functional …

Opiorphin secreted into the human saliva is an endogenous regulator pentapeptide
(QRFSR) showing a pain suppressant effect similar to morphine. We report here a strategy …

Background: The most important investigations since the first publication on opiorphin, in
2006, are summarized in this review. Opiorphin is a human endogenous pentapeptide (Gln …

Cerebrovascular permeability of four modified opioid peptides—[D-Ala2] methionine
enkephalin amide, β-[D-Ala62, 14C-Homoarg69] lipotropin 61-69, α-[D-Ala2, 14C …