title: Changes in brain serotonin levels affect leukocytes, lymphocytes, T-cell subpopulations and natural killer cell activity in rats.
abstract: The intraventricular injection of 5,6-dihydroxytryptamine into desipramine-treated rats caused a marked reduction in serotonin levels 5 and 10 days after treatment without significantly affecting catecholamine levels. In these animals, total leukocytes were increased and lymphocytes decreased. The number of helper T-cells (W3/25+) was significantly decreased after 5 days, whereas the numbers of total T-cells (W3/13+) and suppressor T-cells (MRC OX8) were increased after 10 days. The percentages of total T-cells, helper T-cells and suppressor T-cells were significantly reduced after 5 days. Natural killer cell (NK) activity was markedly reduced after 5 days. This finding suggests that central serotonin-containing neurons might be involved in the regulation of certain parts of the peripheral immune system.
mesh_terms: D015115:5,6-Dihydroxytryptamine / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000378:metabolism*; D001923:Brain Chemistry; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D007694:Killer Cells, Natural / Q000276:immunology*; D007958:Leukocyte Count / Q000187:drug effects*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*; D013601:T-Lymphocytes / Q000145:classification* / Q000276:immunology
chemical_list: D012701:Serotonin; D015115:5,6-Dihydroxytryptamine