CHANGES IN BEHAVIOR, NEUROTRANSMITTERS AND NEUTROPHIL FUNCTION IN OLFACTORY BULBECTOMIZED RATS - EFFECTS OF CHRONIC DESIPRAMINE TREATMENT

The olfactory bulbectomized (OB) rat has been developed as an animal m odel of depression. In the novel 'open field' environment, OB rats sho wed a hyperactivity which was attenuated by chronic treatment with des ipramine (7.5 mg/kg) for 20 days. Neutrophil phagocytosis was suppress ed by the lesion, which was reversed by desipramine administration. Re sults from serum 'crossover' studies and enzyme assay showed that a fa ctor is present in the serum, and cellular enzymes are altered in the OB rat, which may be responsible for abnormal neutrophil phagocytosis. After bulbectomy, the concentrations of noradrenaline (NA) and dopami ne (DA) were decreased, and the 5-hydroxyindole-3-acetic acid (5-HIAA) was increased in the brain limbic system of OB rats. Desipramine trea tment significantly increased the concentration of NA and DA, and slig htly decreased the 5-HIAA. These results suggest that the change in th e neutrophil function following bulbectomy is similar to that reported in the depressed patient. Thus desipramine is an effective antidepres sant for reversing lesion-induced changes in neurotransmitter, behavio ur and neutrophil phagocytosis. (C) 1997 by John Wiley & Sons, Ltd.