AF64A(ethylcholine aziridinium ion)-induced basal forebrain lesion impairs maze performance

Rats were given bilateral injections of ethylcholine aziridinium ion, AF64A (1 nmol/side) into the basal forebrain (BF). One month later, choline acetyltransferase activity was reduced by 25% in the frontal cortex (FC). There was a marked decrease in cortical uptake of [3H]choline, but [3H]GABA and [3H]dopamine uptake was not affected by the injection. Histological analysis confirmed that this dose of AF64A caused acetylcholinesterase staining in the FC to disappear. Acquisition and retention of a T-maze task were impaired in the rats with BF lesions one month after the injection. Acquisition of the water-filled multiple T-maze task was also impaired by AF64A. These observations suggest that the cholinergic component in the BF is involved in spatial memory.