The effect of melatonin on macrophages and cells of the diffuse endocrine system of the spleen

Reaction of Iba-I positive cells in the spleen was studied on the introduction of melatonin. It was detected that oral administration of melatonin (drug «Melaxen») with water (solution 4 mg of the drug per 1 l H2O) for 4 weeks leads to morphological changes in the spleen: increase in quantity of lymphoid nodules, more pronounced in the spleen of animals kept by artificial darkening; decrease in the quantity of cells of the macrophage series (Iba-1+). Exogenous melatonin causes an increase in the number of lymphoid nodules, reducing the levels of catecholamines and serotonin in all immunocompetent spleen cells, reducing histamine content in luminescent cells of red pulp.