The role of oxalate in star fruit neurotoxicity of five-sixths nephrectomized rats.

To investigate the role of oxalate in star fruit neurotoxicity, rats were given star fruit or oxalate after a sham operation or modified five-sixths nephrectomy; namely, star fruit (SC) or oxalate (OxC) for sham-operated rats and star fruit (SNx), calcium gluconate treated star fruit juice (SCaNx), or oxalate (OxNx) for nephrectomized rats. After feedings, none of the rats in SC, OxC, and SCaNx groups developed movement disorders or died, while all rats in SNx group and OxNx group presented movement disorders and two rats in SNx group and four rats in OxNx group died within minute to hour after development of myoclonic jerk and/or tonic-clonic convulsion. The plasma oxalate levels rose significantly only in the SNx group and OxNx group that also presented clusters of generalized spike-waves in the electroencephalographic recordings. In conclusion, oxalate may play a key role in star fruit neurotoxicity in nephrectomized rats and probably in uremic patients.