Tifluadom-induced diuresis in rats. Evidence for an opioid receptor-mediated central action.

Tifluadom dose-dependently induced diuresis in rats after subcutaneous injection and oral application. (+)Tifluadom was at least 100-fold more potent than the (-)enantiomer in inducing diuresis. The diuretic action of tifluadom was dose-relatedly reduced by the opioid receptor antagonists naloxone and MR 2266. Naloxone methobromide did not antagonize the diuretic effect of tifluadom nor did the benzodiazepine receptor blocker Ro 15-1788. These data demonstrate that the diuretic effect of tifluadom is mediated centrally via an agonistic interaction between the drug and opioid receptors.