Effects of an oral adsorbent on cisplatin-induced nephropathy in rats

A 26-week experiment was designed to determine the effect of an oral adsorbent, AST-120 (Kremezin), in rats with cisplatin-induced interstitial nephropathy. We found that creatinine clearance during the 24th week of the experiment was significantly higher in the AST-120-treated rats (n = 11) than in the control animals (n = 11) (1.09 +/- 0.14, vs. 0.63 +/- 0.12 ml/min; p < 0.05). Furthermore, the kidneys, which were examined morphometrically using a computerized image scan, revealed that the AST-120-treated rats had a significantly lower ratio of the tubular cross-sectional area over the cortex and outer medulla cross-sectional area than the control group (0.26 +/- 0.03 vs. 0.38 +/- 0.02; p < 0.05). An additional experiment was conducted to see if the oral adsorbent affects absorption and excretion of intraperitoneally administered cisplatin. There was no difference between the control group (n = 12) and the AST-120-treated group (n = 12) in serum concentration or urinary excretion of cisplatin during a 72-hour period after the injection. The results of our experiments suggest that the oral absorbent, AST-120, blunts progressive deterioration of renal function and nephron architecture in cisplatin nephropathy.