The Role of Ionic Homeostasis in Cisplatin-Induced Neurotoxicity: A Preliminary Study.

Objective: The aim of the present study was to investigate the role of ionic homeostasis in cisplatin (cisdiamminedichloroplatinum (II), CDDP)-induced neurotoxicity. CDDP is a severely neurotoxic antineoplastic agent that causes neuronal excitotoxicity. According to some studies, calcium influx increases, whereas potassium efflux decreases neuronal death. Nimodipine and glibenclamide were used to analyze the role of ionic flows in CDDP-induced neurotoxicity in rat primary cerebellar granule cell (CGC) culture.

Materials and Methods: CGC culture was prepared from the cerebella of Sprague Dawley 5-day-old pups. The submaximal concentration of CDDP was determined and then given with 1, 10, or 50 µM of drugs into culture. Neurotoxicity was investigated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole) assay. One-way analysis of variance, Kruskal-Wallis H test, and Tukey test were applied for statistical analysis.

Results: CDDP induced neurotoxicity in a concentration-dependent manner. Neither nimodipine nor glibenclamide was able to protect CGCs against CDDP neurotoxicity.

Conclusion: By blocking L-type voltage-gated calcium channels, nimodipine did not prevent CDDP neurotoxicity in CGCs. Ca2+ influx via these channels seemed to be insufficient to cause a change in CDDP-induced neurotoxicity. Similarly, glibenclamide failed to prevent CDDP neurotoxicity. Further studies are needed to elucidate the mechanisms of these preliminary results.