IMMOBILIZATION AND LIGHT-DARK CYCLE-INDUCED MODULATION OF SEROTONIN METABOLISM IN RAT-BRAIN AND OF LYMPHOCYTE SUBPOPULATIONS - IN-VIVO VOLTAMMETRIC AND FACS ANALYSES

The effect of immobilization and light-dark cycle on the serotoninergi c system of the n. raphe dorsalis and on the distribution of blood lym phocyte subpopulations was studied in the rat. As was shown by in vivo voltammetry, 10 min immobilization enhanced serotonin metabolism with a maximum 15 min after immobilization. The distribution of the blood lymphocytes into subpopulations was also affected: pan-T and T helper lymphocytes were reduced during immobilization and reached minimum val ues after 20 min recovery. The circadian rhythms of serotonin metaboli sm and the distribution of pan-T and T helper cells exhibited a slight phase shift if compared with each other.