Ethanol-induced flavor aversions in rats with subdiaphragmatic vagotomies

In two experiments rats with subdiaphragmatic vagotomies were compared to sham-operated rats in the acquisition and extinction of a flavor aversion with ethanol as the illness-inducing agent. Vagotomized rats developed aversions equivalent to those of sham-operated rats whether the ethanol was administered intragastrically (Experiment 1) or intraperitoneally (Experiment 2). Because vagotomy eliminates the majority of sensory input from the gastrointestinal tract, ethanol must exert its aversive effects as a blood-borne toxin rather than as a gastrointestinal irritant.