Effects of tramadol stereoisomers on norepinephrine efflux and uptake in the rat locus coeruleus measured by real time voltammetry.

  title={Effects of tramadol stereoisomers on norepinephrine efflux and uptake in the rat locus coeruleus measured by real time voltammetry.},
  author={D M Halfpenny and Luis F. Callado and Sarah E. Hopwood and T. A. Bamigbade and Richard M. Langford and Jonathan A. Stamford},
  journal={British journal of anaesthesia},
  volume={83 6},
Despite its structural similarity to codeine, tramadol is an unusual analgesic whose antinociceptive efficacy is not solely a result of opioid actions but also of its apparent capacity to block monoamine uptake. Tramadol is a mixture of stereoisomers. In this study, we have examined the actions of racemic, (+)- and (-)-tramadol, in addition to O-desmethyltramadol (the main human metabolite), on electrically evoked norepinephrine efflux and uptake in the locus coeruleus brain slice, measured by… 

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