Rat lymphocytes produce and secrete acetylcholine in dependence of differentiation and activation.

Previous data from this laboratory suggested for the first time that immune cells of the immune system of different species are capable to synthesize the neurotransmitter acetylcholine. In the present study we detected the RNA message for choline acetyltransferase in thymic, splenic and peripheral blood lymphocytes of rats using RT-PCR. Furthermore, using a sensitive radioimmunoassay, we measured acetylcholine in thymic, splenic and peripheral blood lymphocytes. T-cells were found to contain about three times the amount of acetylcholine as compared to B-cells, and CD4+ cells showed significantly higher levels as compared to CD8+ cells. Mitogenic stimulation with PHA increased the acetylcholine levels in lymphoid cells as well as the release into the supernatants.