Rat Spleen Lymphocytes Contain an Immunoactive and Bioactive Luteinizing Hormone-Releasing Hormone

An interaction between the immune and endocrine systems has been long known. This association is further strengthened by the finding that splenic lymphocytes have the capacity to produce molecules similar to if not the same as classical hormones, including several members of the opiate family, PRL, GH, and neuropeptide Y. Because of such findings and because of information from other laboratories suggesting that LHRH might have direct effects upon the immune system, we hypothesized that immune cells themselves might contain LHRH. Lymphocytes were purified from spleens of intact adult male Sprague-Dawley rats and the cells were lysed with sodium hydroxide. The concentration of immunoreactive LHRH was 403 ± 184 pg/20 × 106 lymphocytes. Increasing amounts of lymphocyte lysate displaced [ 125-I]LHRH from LHRH antibody in a manner parallel to that produced by synthetic hypothalamic LHRH, suggesting immunologic similarity between lymphocyte and hypothalamic LHRH. Lymphocyte LHRH-like immunoactivity coeluted fro...