Splenic norepinephrine depletion following acute stress suppresses in vivo antibody response.

Exposure to an intense acute stressor immediately following immunization leads to a reduction in anti-KLH IgM, IgG, and IgG2a, but not IgG1. Stress also depletes splenic norepinephrine (NE) content. Immunization during pharmacological (alpha-methyl-p-tyrosine) or stress-induced splenic NE depletion results in antibody suppression similar to that found in rats immunized prior to stressor exposure. Prevention of splenic NE depletion during stress by tyrosine, but not pharmacological elevation (mirtazapine) of NE, resulted in normal antibody responses. These data support the hypothesis that splenic NE depletion is necessary and sufficient for stress-induced suppression of antibody to a T-cell dependent antigen.