• Opioids, extensively used as analgesics, markedly depress ventilation, particularly the ventilatory responsiveness to hypercapnia in humans and animals predominantly via acting on mu receptors. (silverchair.com)
  • But opioids cause respiratory depression, a particular problem when they are used as analgesics. (silverchair.com)
  • The rigid structural and stereochemical requirements essential for the analgesic actions of morphine and related opioids led to the theory that they produce their effects by interacting with a specific receptor. (opioids.wiki)
  • DAMGO ([D-Ala2, N-MePhe4, Gly-ol]-enkephalin) is a synthetic opioid peptide with high μ-opioid receptor specificity. (wikipedia.org)
  • Structures of DAMGO bound to the µ opioid receptor reveal a very similar binding pose to morphinans. (wikipedia.org)
  • Intravenous (i.v.) administration of μ opioid receptor (MOR) agonists (fentanyl, alfentanil, remifentanil, and morphine) evoked scratching in a dose- and time-dependent manner. (ewha.ac.kr)
  • Antagonist studies revealed that i.v. administration of an opioid receptor antagonist (naltrexone, 0.0032-0.1 mg/kg) dose dependently attenuated scratching induced by i.v. fentanyl (0.018 mg/kg) or morphine (1 mg/kg). (ewha.ac.kr)
  • Together, these data suggest that MOR, not other opioid receptor types or histamine, mediates scratching evoked by opioid analgesics. (ewha.ac.kr)
  • 1 The concept that there is more than one type of opioid receptor arose to explain the dual actions of the synthetic opioid nalorphine, which antagonises the analgesic effect of morphine in man but also acts as an analgesic in its own right. (opioids.wiki)
  • Martin (1967) concluded that the analgesic action of nalorphine is mediated by a receptor, later called the k -opioid receptor, that is different from the morphine receptor. (opioids.wiki)
  • 2 Evidence for multiple receptors, m , k and s , came from the demonstration of different profiles of pharmacological activity in the chronic spinal dog with the prototype agonists morphine, ketazocine and N-allylnormetazocine (SKF 10047). (opioids.wiki)
  • We hypothesize that a neutrophil-mediated endogenous analgesic mechanism is responsible for sex differences in nociception secondary to oral squamous cell carcinoma (SCC). (frontiersin.org)
  • We infer that rG-CSF-induced Ly6G + neutrophils drive an endogenous analgesic mechanism. (frontiersin.org)
  • However, a peripherally selective opioid antagonist (quaternary naltrexone, 0.0032-0.32 mg/kg) did not block i.v. fentanyl- or morphine-induced scratching. (ewha.ac.kr)
  • Furthermore, in in vivo studies it was observed that naloxazone selectively blocked morphine-induced antinociception but did not block morphine-induced respiratory depression or the induction of morphine dependence. (opioids.wiki)
  • In sharp contrast, these responses were not observed when the DAMGO microinjection was made in the middle MRR or rostral MRR. (silverchair.com)
  • 3-HM's levorotatory stereoisomer, norlevorphanol, in contrast to (+)-3-HM, is an opioid analgesic . (cloudfront.net)
  • In 1803, Sertürner isolated a crystalline sample of the main constituent alkaloid, morphine, which was later shown to be almost entirely responsible for the analgesic activity of crude opium. (opioids.wiki)
  • Intrathecal (i.t.) administration of peptidic MOR agonist [D-Ala 2 , N-Me-Phe 4 ,Gly 5 -ol]-enkephalin (DAMGO, 0.00032-0.01 mg) evoked scratching, but i.v, DAMGO (0.01-1 mg/kg) did not increase scratching. (ewha.ac.kr)
  • Local administration of DAMGO into the caudal MRR also reduced ventilation and the response to carbon dioxide by 22% and 28%, respectively. (silverchair.com)
  • Further addressing the molecular basis of opioid peripheral analgesia, we recently demonstrated that the phosphoinositide 3-kinase gamma (PI3Kγ)/AKT signaling pathway is the first step between the activation of μ-opioid receptors by morphine and selective agonists and the stimulation of nitric oxide control of peripheral analgesia. (biomedcentral.com)
  • An animal study in rats did find O-DSMT had analgesic effects and those were blocked by a MOR antagonist (Valle, 2000). (thedrugclassroom.com)
  • Furthermore, U50488 lost its peripheral analgesic effect in PI3Kγ null mice. (biomedcentral.com)
  • This study extends a previously study of our group suggesting that PI3Kγ/AKT/nNOS/NO is an important analgesic pathway in primary nociceptive neurons. (biomedcentral.com)
  • DAMGO has been used in experimental settings for the possibility of alleviating or reducing opiate tolerance for patients under the treatment of an opioid. (wikipedia.org)
  • 2004) Intra-amygdalar injection of DAMGO: effects on cFos levels in brain sites associated with feeding behavior. (algosinc.com)
  • [email protected] Received 28 May 2007 Accepted as revised 13 August 2007 Opiates such as morphine also produce biphasic effects. (studyres.com)
  • DAMGO did not alter the responses of sensory fibres in uninjured nerves. (biomedcentral.com)
  • These drugs are identical ( e.g. , morphine) or very much alike the many active alkaloids that are present in opium sap. (medscape.com)
  • In fact, in contemporary medicine, opioid analgesics remain the most potent painkillers that we have and consequently that we use in the pharmacologic treatment of acute (perioperative) and chronic pain. (medscape.com)
  • The paraventricular nucleus of the thalamus (PVT) is involved in drug addiction-related behaviors, and morphine is a widely used opioid for the relief of severe pain. (jneurosci.org)
  • 1995). Agonists of the cannabinoid (CB) CB1 receptor (CB1R) were found to be effective analgesics in a variety of pain tests. (studyres.com)
  • O-Desmethyltramadol (O-DSMT) is an opioid that has primarily been used indirectly due to it being a primary metabolite of the analgesic tramadol. (thedrugclassroom.com)