A role for taste aversion learning in FLA-57 induced reductions of voluntary alcohol intake

It has been proposed by Amit, Brown and colleagues that the reduction in voluntary alcohol intake observed after the administration of FLA-57 in rats can be attributed to decreased NE levels produced by FLA-57. Our studies investigated whether a conditioned taste aversion could better explain this phenomenon. In the key study, two groups of rats were injected with FLA-57 or Ringers before drinking alcohol for five days, while a third group was injected with FLA-57 before exposure to intragastrically intubated (untasted) alcohol in amounts identical to those in the tasted group. Results showed that only the FLA-57 group that tasted alcohol reduced subsequent voluntary alcohol intake. When a CTA was precluded, allowing only for an effect due to reduced NE, no reduction was observed. This suggests that FLA-57 reduces VAI, not via reduced NE levels, but by a conditioned taste aversion. A second study, utilizing saccharin instead of alcohol, generally supported this conclusion. While these results support a CTA explanation, it is possible that under other conditions FLA-57 might produce a central pharmacological effect.