Abstract
Intramuscular administration of the central analgesics fentanyl and Analgin (dipyrone) along with the pain mediators cholecystokinin (CCK), glutamate, ATP, and adrenaline, and the analgesia mediator adenosine, which have weak penetration into the CNS, induced maximal analgesic effects at minimally effective doses in the tailflick test in rats. The minimal effective doses of Analgin and fentanyl decreased by factors of 50‐220 in response to combined i.m. administration of each of the analgesics with CCK, glutamate, ATP, adrenaline, and adenosine at subthreshold does which were ineffective when given alone. Intragastric administration of lidocaine and subdiaphragmatic gastric vagotomy completely blocked the analgesic effects of these combinations. These data lead to the conclusion that peripherally acting pain and analgesia mediators given systemically potentiate the central analgesic actions of Analgin and fentanyl via stimulation of the chemoreceptors of vagal afferents in the gastric mucosa.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
