Neuropathology and amphetamine-induced turning resulting from AF64A injections into the striatum of the rat

The putative specific cholinergic neurotoxin AF64A was prepared by a micro-scale procedure which afforded the neurotoxin in greater than 95% purity and was microinjected unilaterally into the striatum of male albino rats. The AF64A-injected animals displayed amphetamine- and apomorphine-induced ipsilateral turning indicating disruption of normal striatal pathways. These turning effects were absent in the control injected animals. Histological examinations of the brains revealed that AF64A in amounts as low as 1 nmole produced regions of necrosis in the striatum in some cases extending along the cannula tract up to and including the cortex. These results indicate that the striatum is highly sensitive to relatively low doses of AF64A, and that consideration should be given to the possibility of gross tissue damage when interpreting behavioral data.