fentanyl brands

Molecular formula: C22H28N2O

Fentanyl binds to opioid receptors, especially the mu opioid receptor, which are coupled to G-proteins. Activation of opioid receptors causes GTP to be exchanged for GDP on the G-proteins which in turn down regulates adenylate cyclase, reducing concentrations of cAMP. Reduced cAMP decreases cAMP dependant influx of calcium ions into the cell. The exchange of GTP for GDP results in hyperpolarization of the cell and inhibition of nerve activity. The aim of the present study was to describe the activity of a set of opioid drugs, including partial agonists, in a cell system expressing only mu opioid receptors. Receptor activation was assessed by measuring the inhibition of forskolin-stimulated cyclic adenosine mono phosphate (cAMP) production. Efficacies and potencies of these ligands were determined relative to the endogenous ligand beta-endorphin and the common mu agonist, morphine. Among the ligands studied naltrexone, WIN 44,441 and SKF 10047, were classified as antagonists, while the remaining ligands were agonists. Agonist efficacy was assessed by determining the extent of inhibition of forskolin-stimulated cAMP production. The rank order of efficacy of the agonists was fentanyl = hydromorphone = beta-endorphin > etorphine = lofentanil = butorphanol = morphine = nalbuphine = nalorphine > cyclazocine = dezocine = metazocine >or= xorphanol. The rank order of potency of these ligands was different from that of their efficacies; etorphine > hydromorphone > dezocine > xorphanol = nalorphine = butorphanol = lofentanil > metazocine > nalbuphine > cyclazocine > fentanyl > morphine >>>> beta-endorphin. These results elucidate the relative activities of a set of opioid ligands at mu opioid receptor and can serve as the initial step in a systematic study leading to understanding of the mode of action of opioid ligands at this receptor. Furthermore, these results can assist in understanding the physiological effect of many opioid ligands acting through mu opioid receptors. Diabetic neuropathy is one of the most frequent complications of diabetes mellitus. Therefore, the present study was designed to investigate the anti-hyperalgesic mechanism of fentanyl in a mouse model of streptozotocin-induced diabetic neuropathy. The antinociceptive response was assessed by recording the latency in a tail-flick test. The tail-flick latency in diabetic mice was significantly shorter than that in non-diabetic mice. Fentanyl, at doses of 3 and 10 ug/kg, s.c., produced a dose-dependent increase in the tail-flick latencies in diabetic mice. While fentanyl (3 ug/kg, s.c.) did not produce a significant inhibition of the tail-flick response in non-diabetic mice, it significantly prolonged the tail-flick latency in diabetic mice to the same level as the baseline latency in non-diabetic mice. Although pretreatment with naloxone (3 mg/kg, s.c.) completely antagonized fentanyl-induced antinociception in non-diabetic mice, it had no effect on the antinociceptive effect of fentanyl in diabetic mice. Pretreatment with either of the voltage-gated sodium channel openers fenvarelarte and veratridine practically abolished the antinociceptive effects of fentanyl in diabetic mice. However, neither fenvarelate nor veratridine affected the antinociceptive effect of fentanyl in non-diabetic mice. These results suggest that the anti-hyperalgesic effect of fentanyl is mediated through the blockade of sodium channels in diabetic mice, whereas opioid receptors mediate the antinociceptive effect of fentanyl in non-diabetic mice. Tolerance to opioids frequently follows repeated drug administration and affects the clinical utility of these analgesics. Studies in simple cellular systems have demonstrated that prolonged activation of opioid receptors produces homologous receptor desensitization by G-protein receptor kinase mediated receptor phosphorylation and subsequent beta-arrestin binding. To define the role of this regulatory mechanism in the control of the electrophysiologica

Source: PubChem (NCBI) · compound 3345