Aim: Study cellular interaction in central and peripheral immune organs at prolonged all-day illumination in an experiment on rabbits.
Introduction: Prolonged all-day illumination is considered nowadays as one of the stress-factors for the living organism and causes malfunctions of the neuroendocrine system and may initial immune dysfunction.
Methods: Experimental rabbits (n=10) were in artificial lighting in the day and electric lighting at night during 12 months. Control animals (n=5) were kept in natural day and night lighting conditions. Cell density in immune organs (thymus, bone marrow, spleen) were measured in surface area which was determined by a rectangle 100×100μm. The results were processed with standard statistical methods and reported as mean±standard deviation (SD).
Results: The cell density in the thymus and the bone marrow was decreased: in the cortex of the thymus was 359.6±2.9, in the medullar part – 250,8±2,9, in the bone marrow – 176.4±2.9 (cells in 100×100μm). An intensified formation of the connective tissue, an increasing of involutive processes and degenerative changes of lymphocytes were microscopically found in the spleen and the thymus. The cell density in the spleen was decreased too: in T zone – 235.8±3.7, in B-zone – 159.5±1.9 (cells in 100μm×100μm). The causes of these changes, probably, may be decrease of the differentiation and migration of lymphocytes as result negative influence of the prolonged light on central immune organs.
Conclusion: These changes in organs of the immune system indicate both a premature aging of the spleen and the thymus and probably of all the immune system. Significant reduction in cell density in the immune organs associate with negative effects of the chronic light stress and leads to expressed immune dysfunction.