Morphofunctional reaction of Iba-I and MHC-II positive cells of the spleen on the injection of melatonin

Reaction of Iba-I and MHC-II positive eells 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 H20) 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 eells of the macrophage series (Iba-1+) and activated macrophages (MHCII+) in the spleen of animals kept by daylight; low changes in the quantity of eells of the macrophage series (Iba-1+) and activated macrophages (MHCII+) in the spleen of animals kept by artificial darkening. The most sensitive to lighting conditions animals injected with melatonin, are PALM, marginal sinus and subeapsular area of the red pulp of the spleen.