RECOVERY FROM LEAD-INDUCED BIOCHEMICAL AND IMMUNOLOGICAL ALTERATIONS FOLLOWING COMBINED TREATMENT WITH DMSA AND CALCIUM DISODIUM EDTA IN RATS

The therapeutic potential of meso 2,3-dimercaptosuccinic acid (DMSA) a nd calcium disodium ethylenediamine tetraacetic acid (CaNa(2)EDTA) alo ne or in combination in reducing levels of lead in blood and other sof t organs and reversing lead induced biochemical and immunological alte rations were investigated after chronic low level lead exposure. Lead exposure produced a significant adverse effect on few selected haemato poietic, nervous, testicular and immunological variables. Conventional 5-day treatment with both DMSA and CaNa(2)EDTA individually was, effe ctive in inducing elimination of lead but the recovery of the altered biochemical and clinical indices was moderate. When given in combinati on for 5 days, (DMSA was administered orally twice daily before intrap eritoneal CaNa(2)EDTA administration) they were more effective in depl eting body lead burden and providing recoveries in the altered biochem ical parameters. Along with the rapid removal of lead from body stores after combined treatment, the immunological variables also recovered spontaneously. However, the altered CNS disorders remained practically unchanged following 5 days of chelation therapy. Lead induced testicu lar alterations also showed some recoveries after combined treatment. The results indicate that combined DMSA and CaNa(2)EDTA treatment coul d, be more beneficial than individual treatment with any of these agen ts. (C) 1998 Elsevier Science B.V. All rights reserved.