The ultrastructural ionic fixation technique localizing acetylcholinesterase activity, reveals simultaneously acetylcholine-like cation in the synaptic vesicles of the motor nerve terminals.
A new cytochemical technique is proposed for side by side localization of acetylcholine and of acetylcholinesterase activity of motor end-plate at ultrastructural level. The technique is based on the simultaneous "ionic fixation" of vesicular acetylcholine and of histochemical copper thiocholine precipitate with phosphomolybdic acid: the molybdic heteropolyanion forms insoluble salts with these two quaternary ammonium cations, providing in situ "acetylcholine phosphomolybdate" and "copper thiocholine phosphomolybdate". Both of them are osmium resistant; the electron dense precipitates allow for a fine localization of acetylcholine and acetylcholinesterase activity at electron microscopic level.
D000109:Acetylcholine / Q000378:metabolism*; D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D006651:Histocytochemistry; D007366:Intercostal Muscles / Q000294:innervation; D051379:Mice; D009045:Motor Endplate / Q000201:enzymology / Q000378:metabolism* / Q000648:ultrastructure; D009469:Neuromuscular Junction / Q000378:metabolism*; D013572:Synaptic Vesicles / Q000201:enzymology / Q000378:metabolism*
D000110:Acetylcholinesterase; D000109:Acetylcholine