Lithium induced toxicity in rats: a hematological, biochemical and histopathological study

Lithium (Li(+)) salts are commonly used in treating bipolar diseases. As physicians frequently keep the patients on long-term lithium therapy, awareness of the numerous side effects and pathogenesis of this lightest alkali metal is needed for such treatments. The current study was designed to evaluate the toxic effect of small doses of lithium nitrate in rats. In the present study we showed that the oral gavage feeding of lithium nitrate (20 mg Li/kg body wt) for 7 weeks on every alternate day to male albino wistar rats elicited a significant alterations in gross hematological values owing to hypochromic anemia and leucocytosis. Erythrocyte sedimentation rate (ESR) and clotting time depicted higher values and animals exhibited icteric condition. Serum levels of hexose, cholesterol and blood urea elevated; however, proteins depleted markedly. A significant increase in serum calcium and phosphorus has also been registered in lithium salt treated animals. The enzyme activities of alkaline phosphatase (Alpase) and acid phosphatase (Acpase) diminished depicting the disturbed general physiological status while there was a marked rise in the activities of transaminases (GOT and GPT) reflecting a stimulating transamination reaction in hepatic and renal tissues. The histopathological picture of the kidney tissues revealed many deformative alterations. Necrosis, binucleated cells and Kuffer's cells are visible in renal tissue. The epithelium lining of renal tissue was damaged and there were also some marked changes in glomerular region apart from intracellular alterations in corticomedulary region. The results of present study suggest that small doses of lithium induce toxicity in rats.