µ-Opioid receptor activation by tramadol and O-desmethyltramadol (M1)

  title={µ-Opioid receptor activation by tramadol and O-desmethyltramadol (M1)
  author={Kouichiro Minami and Yuka Sudo and Kanako Miyano and Robert S. Murphy and Yasuhito Uezono},
  journal={Journal of Anesthesia},
Tramadol has been used as an analgesic for several decades. µ-Opioid receptors (µORs) are the major receptors that mediate the analgesic effects of opioids. Although µORs have been thought to be one of the sites of action of tramadol, there has been no report that directly proves whether tramadol is an agonist of μOR or not. In this study, we examined the effects of tramadol and its main active metabolite O-desmethyltramadol (M1), on the function of µORs using Xenopus oocytes expressing cloned… 
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