The effects of chronic lithium chloride administration on some behavioural and immunological changes in the bilaterally olfactory bulbectomized rat

Abstract

The effect of chronic lithium chloride (3 mmol/kg for 15 days) on the 'open field' activity and some aspects of immune function was studied in bilaterally olfactory bulbectomized and sham-operated rats. Chronic lithium chloride administration did not reverse the hyperactivity of the bulbectomized rats in the 'open field', neither did it affect the growth rate significantly. Lithium chloride treatment reversed the deficit in the neutrophil phagocytic response and slightly reversed the deficit in lymphocyte proliferation induced by mitogens that resulted from bulbectomy. The reduction in neutrophil catalase activity, and the increase in superoxide dismutase activity, that occurred following bulbectomy was reversed by chronic lithium treatment. However, the reduction in the proportion of lymphocytes, and the increase in the proportion of neutrophils that occurred in the bulbectomized rats was not reversed significantly by chronic lithium treatment. Chronic lithium treatment reversed the deficit in noradrenaline in the amygdaloid cortex and hypothalamus of the bulbectomized rats and the reduction in the dopamine concentration in the amygdaloid cortex. No changes in the concentrations of 5-HT and 5-HIAA could be detected in any of the brain regions studied. Thus there is a disparity between the lack of effect of lithium chloride on 'open field' behaviour and its beneficial effects in correcting some of the immune and neurotransmitter deficits which were observed in the bulbectomized rats.