Choline acetyltransferase activity and [3H]quinuclidinylbenzilate binding in brains of scrapie-infected hamsters.

Choline acetyltransferase (ChAT) activity and [3H]quinuclidinylbenzilate binding were studied in the brain of scrapie-infected hamsters and sham inoculated controls. Although scrapie-infected hamsters showed no reduction of ChAT activity compared to the controls, they showed a decrease in the affinity and maximum number of post-synaptic muscarinic receptors. Scrapie virus thus alters the cholinergic system at the post-synaptic rather than at the pre-synaptic level.