Behavioral consequences of chelator administration in acute cadmium toxicity

The conditioned flavor-aversion paradigm was used to assess the toxicity of acutely administered cadmium and the interaction of cadmium with the heavy-metal chelating agents dimercaprol (BAL) and dimercaptosuccinic acid (DMSA). Shortly after consuming saccharin, rats received ip administration of cadmium either alone or in combination with sc administration of BAL or DMSA. Three days later they were given the choice between consuming saccharin or water, and saccharin preferences were recorded. When compared to rats receiving either nothing or the vehicle, rats receiving cadmium displayed significant reductions in saccharin preference (i.e., conditioned flavor aversions). BAL and DMSA were also capable of producing conditioned flavor aversions when given alone. Rats receiving cadmium in combination with either BAL or DMSA displayed significant, but not complete attenuations of conditioned flavor aversions when compared to the flavor aversions of rats receiving cadmium alone. Chelator-induced blockade of cadmium-induced flavor-aversion conditioning was not obtained when BAL or DMSA administration was delayed by 4 hr. Attenuation of cadmium-induced aversions by BAL and DMSA extends earlier findings of an attenuation of lead-induced flavor-aversion conditioning by these complexing agents, and thus demonstrates further the utility of the flavor-aversion conditioning paradigm in characterizing metal-chelator interactions.