Abstract
A partially purified morphine-like peptide ‘enkephalin’ (PPE) extracted from bovine brain elicted pronounced apparent analgesia after injection into the periaqueductal gray matter of rat brain. This analgesia was reversed by the opiate antagonist naloxone in a dose-dependent fashion. Analgesia was more rapid in onset and much shorter in duration after PPE than after morphine administration. Analgesia was elicited only by those ion exchange column fractions of PPE that competed potently for opiate receptor binding. No analgesia could be detected when PPE or morphine injections were administered at a site 2 mm lateral to the periaqueductal gray matter. The potencies of synthetic methionine- and leucine-enkephalin in eliciting analgesia were less than 1% of those of partially purified enkephalin extracts when doses of equivalent ability to compete for opiate receptor binding were compared.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.