Neurotoxicity of lindane and picrotoxin: neurochemical and electrophysiological correlates in the rat hippocampus in vivo.

In the present study, we compared in vivo changes of extracellular amino acid levels and nucleotide derivatives to a single ip dose of lindane (10-60 mg/kg) and picrotoxin (5 mg/kg) in the hippocampus of halothane anaesthetized rat by microdialysis-coupled HPLC analysis. Brain activity was monitored by EEG. The effects of lindane and picrotoxin on EEG pattern of rats as well as on hippocampal amino acid and nucleotide status were studied in 0-50 min, 50-100 min and 100-150 min periods post-dosing. Significant decreases in Glu and Asp were found after picrotoxin treatment. After 50-100 min post-dosing, hippocampal hypoxanthine and inosine levels increased to both lindane (10 mg/kg) and picrotoxin whereas xanthine and uridine levels increased to picrotoxin, only. Lindane elicited a dose-dependent occurrence of negative spikes accompanied with rhythmic activity at 4-5 Hz. The picrotoxin-induced 4-5 Hz activity did not display negative sharp waves and was accompanied by 10 Hz oscillations.