Abstract
The PC12 clone of a rat pheochromocytoma is able to synthesize acetylcholine. The amount of acetylcholine synthesized, and the specific activity of choline O-acetyltransferase (acetyl-CoA:choline O-acetyltransferase, EC 2.3.1.6), varies as a function of the culture growth curve and is dependent on cell density. The specific activity of choline acetyltransferase is increased by nerve growth factor, growth-conditioned medium from a variety of cell types, and adenosine 3':5'-monophosphate. Finally, the PC12 cell line is able to form cholinergic synapses with a clonal cell line of skeletal muscle origin.