Characterization of a kappa-agonist-like antinociceptive action of tifluadom

The novel benzodiazepine tifluadom was compared with a selection of proposed mu- and kappa-opiate agonists using a combined heat/pressure nociceptive paradigm. Calculation of the relative potency ratios to the nociceptive stimuli revealed a distinction between mu- and kappa-agonists. The potency ratio yielded by tifluadom coincided with that displayed by the kappa-agonists and this finding is discussed in relation to morphine withdrawal and radioligand binding studies.