SEROTONIN REUPTAKE INHIBITORS REVERSE THE IMPAIRMENTS IN BEHAVIOR, NEUROTRANSMITTER AND IMMUNE FUNCTIONS IN THE OLFACTORY BULBECTOMIZED RAT

This experiment investigated the effects of chronic treatment with serotonin reuptake inhibitors, fluvoxamine (10 mg/kg, i.p.) and sertraline (10 mg/kg, i.p.), for 20 days on the behaviour, neurotransmitter concentrations and immune functions in the olfactory bulbectomized (OB) rat model of depression. Following fluvoxamine and sertraline administration, the hyperactive behaviour of the OB rat in the 'open field' was significantly attenuated. In the elevated plus-maze, an increase in the number of entries into the open arms and a decrease in the time spent on the closed arms were also largely reversed in the OB rat after fluvoxamine and sertraline treatment. Fluvoxamine and sertraline treatments reversed the decrease in the brain concentrations of noradrenaline (NA) of the OB rat and the increase in the 5-hydroxyindole-3-acetic acid (5-HIAA) concentration. Fluvoxamine and sertraline treatment also significantly reversed the suppression of lymphocyte proliferation in the OB rat. However, only the chronic administration of fluvoxamine significantly improved depressed neutrophil phagocytosis, sertraline being without effect on this immune parameter.