The effect of the opioid-benzodiazepine, tifluadom, on ingestive behaviors.

A large body of evidence has suggested a role for the endogenous opiates and their receptors in the regulation of appetite. In this study, we report on the effects of tifluadom, a noval opiate with a benzodiazepine-like structure and preferential activity at the kappa opiate receptor, on ingestive behaviors. Tifluadom increases food intake in rats without altering water intake. Tifluadom's effect on feeding is more potent than that of morphine or ketocyclazocine and equivalent to that of butorphanol. The effect is partially resistant to naloxone antagonism. Tifluadom is more potent when administered subcutaneously than when given intraperitoneally. These data provide further support for the concept that kappa opiate receptors represent an important component of the natural feeding drive.