Evidence that an ATPase and a protonmotive force function in the transport of acetylcholine into storage vesicles.

PC12, a clonal line of rat pheochromocytoma, accumulates newly synthesized acetylcholine in storage granules. The accumulation of acetylcholine in PC12 granules, but not acetylcholine synthesis, was inhibited by treatment of the cells with any of several inhibitors of energy metabolism. These included nigericin, carbonyl cyanide p-trifluoromethoxyphenylhydrazone, dicyclohexylcarbodiimide, and iodoacetate. Valinomycin alone and oligomycin were without effect. Except for iodoacetate, these agents did not exert their effects on acetylcholine storage by depleting the cells of ATP.