IMMUNOMODULATION FOLLOWING ZINC SUPPLEMENTATION DURING CHELATION OF LEAD IN MALE-RATS

Influence of zinc supplementation (30 and 45 mg kg-1, orally once for 5 days) during chelation of lead (0.3 mmol kg-1, chelating agent, i.p. , once for 5 days) on some selected variables of the immune system was investigated in male rats. Treatment with CaNa2EDTA either alone or i n combination with zinc (30 mg kg-1) produced a significant recovery i n lead induced alteration in primary antibody forming cells to T-depen dent antigen and the delayed-type hypersensitivity response to bovine albumin. However, biologically significant recovery was observed only with zinc at a dose of 45 mg kg-1. It is assumed that zinc depletion d uring lead exposure and chelation treatment lead to harmful effects on cellular proliferation by inhibiting DNA synthesis and various enzyme s during mitosis. The zinc supplementation fulfills this requirement d uring proliferation and clonal expansion of immunocompetent cells augm enting the immune system.