Influence of lithium on neutrophil granulocyte distribution and turnover

In 10 psychiatric patients marrow granulocyte reserve, marginal granulocyte pool, granulocyte mobilization into skin chamber, serum lysozyme activity was estimated before and ten days after the lithium treatment. In all patients the peripheral neutrophil count rose significantly. The marrow granulocyte reserve did not change markedly. Moreover, the marginal granulocyte pool as expressed in percentages diminished. Serum lysozyme activity, total leukocyte mobilization, and blood granulocyte clearance remained unchanged. However, the serum lysozyme activity index fell significantly. The in vitro addition of lithium to the suspension of granulocytes obtained from healthy persons reduce the granulocyte adherence especially in concentrations similar to those induced in treated patients. Our findings suggest that lithium in vivo may diminish the granulocyte adherence resulting in the prolonged intravascular half-life time of the cells. Thus, the cell accumulation in the vascular bed seems to be the main reason for lithium induced granulocytosis rather than the intensification of marrow granulocyte system proliferation.