Angiotensin II mediates a conditioned taste aversion in water-replete rats.

Many compounds that exert an influence on behavioral processes will, under the unique conditions of the conditioned taste aversion (CTA) procedure, cause animals to avoid consuming an otherwise preferred fluid. While angiotensin II (ANG II) is a peptide with a number of behavioral and physiological actions, previous research did not support its role as an agent capable of inducing a CTA. Those studies used fluid deprivation to induce fluid intake and only a single conditioning trial. Fluid deprivation can elevate endogenous ANG II levels that may have interfered with or masked the ability of ANG II injections to exert an effect as a CTA-inducing agent. The present study reassessed the ability of ANG II to induce a CTA using fully hydrated animals and a number of conditioning trials. ANG II was able to induce a significant taste aversion at a dose five times lower than that used in previous studies.