Neurochemical effects of IDPN on the mouse brain.

Treatment of mice with IDPN (4 injections of 1 gm/kg on alternate days) produced a characteristic syndrome of abnormal movements which was associated with neurotransmitter changes in the extrapyramidal and other regions of the brain. A decrease in the concentration of GABA was observed in the striatum and hippocampus both 1 and 10 days after the last injection, along with a transient decrease in the cerebral cortex. In addition, the specific binding of GABA was increased by this treatment in the striatum and cerebral cortex but reduced in the cerebellum. Other striatal changes included a transient increase in dopamine content and a decrease in choline acetyltransferase activity. No biochemical or behavioral changes were observed after acute injection of IDPN or following 4 injections of the non-neurotoxic analog BAPN. These neurochemical alterations may play a role in the abnormal movements produced by IDPN.