Conditioned enhancement of antibody production is disrupted by insular cortex and amygdala but not hippocampal lesions

Pavlovian conditioning procedures can be used to activate the immune system . A reliable conditioned increase of antibody production can be obtained in rats that have previously received a gustative or odor stimulus as the con ditioned stimulus paired with an antigen, by exposing the animals to the co nditioned stimulus alone. We showed evidence that an excitotoxic lesion bil aterally applied into the insular cortex or the amygdala, but not into the dorsal hippocampus, impaired the acquisition of both odor and gustatory con ditioned immune enhancement. We found no effects of lesions on normal antib ody production. These results suggest that the amygdala and the insular cor tex are involved in the neural-immune interactions: that mediate conditione d immunity. (C) 1999 Academic Press.