Learned taste aversions in rats as a function of dosage, concentration, and route of administration of LiCl

Rats drank a 15% sucrose solution for 10 min and were then injected intraperitoneally with various volumes of 0.15 M LiCl to produce a learned taste aversion to the sucrose. A dose response curve was obtained between the volume of 0.15 M LiCl injected and the degree of aversion. With additional groups, the LiCl concentration was varied inversely with volume injected and it was found that the aversion was dependent on the absolute quantity of LiCl and not on the concentration or volume of solution. LiCl was also found to be equally effective in producing learned aversions whether administered intraperitoneally, subcutaneously, or by stomach tube. The dose-response curve indicated that a very strong aversion occurs at a dose of 3.0 mEq/kg and that the threshold dose for producing an aversion is approximately 0.15 mEq/kg. The threshold dose was discussed in relation to the amount normally given to human patients as a therapeutic dose. It was concluded that the rat is highly sensitive to learning a taste aversion with LiCl.