Locus ceruleus and immunity. I. Suppression of plaque-forming cell response and antibody production in rats with lesioned locus ceruleus.

Earlier research had demonstrated that lesions placed in different brain structures may alter the immune responsiveness. Norepinephrine is one of neurotransmitters which plays a role in immune reactions, and the locus ceruleus represents the largest group of norepinephrine-containing neurons in the brain. The present study concerns, therefore, the relationship between the locus ceruleus and humoral immune reactions. For this purpose, rats with electrolytically induced lesions in locus ceruleus were used in the study. Locus ceruleus-lesioned animals showed a decreased ability to produce hemolysin-releasing cells, hemagglutinins, and antibodies to bovine serum albumin. In brain-lesioned rats, thymus tended to the smaller in size, and there was a depletion of CD4+ helper/inducer lymphocyte population in the peripheral blood.