Changes of lithium elimination in acute polyuric renal failure caused by cisplatin and mercuric chloride

Changes in lithium elimination were studied under the condition of experimentally induced polyuric acute renal failure by cisplatin (6 mg/kg body wt) or HgCl2 (3 mg/kg body wt). The histologically proven lesions of tubuli were associated with the decrease of plasma clearance of lithium (C(Li)) and polyfructosan-S (CP(FS). The decrease of these clearance values was not proportional and the ratio C(Li)/CP(FS) (indicating renal fractional excretion of Li+) increased significantly (p less than 0.01). The increase of C(Li)/CP(FS) was related to the increase of renal fractional sodium excretion (FENa) (p less than 0.01). The results suggest that the impairment of tubular cells by cisplatin or HgCl2 caused the decrease of tubular reabsorption of Li+ and Na+. From the pharmacokinetic point of view, these experiments suggest that changes in tubular transport of drugs should be taken into account in their dosing adjustment in patients with acute polyuric tubular lesion.