Relation between the content of acetyl-coenzyme A and acetylcholine in brain slices.
Slices of rat caudate nuclei were incubated in vitro in media containing, among other constituents, three different concentrations of glucose (0.5, 2 and 10 mM), 0.2 mM-choline, paraoxon as an inhibitor of cholinesterase, and 5 mM- or 30 mM-K+. After 30 and 60 min of incubation, the concentrations of acetyl-CoA, acetylcholine and choline in the tissue and of acetylcholine in the incubation medium were measured. The content of acetyl-CoA in the sliced varied in direct relation to the concentration of glucose in the incubation medium. The content of acetylcholine in the slices and, in experiments with high K+, also the amount of acetylcholine released into the incubation medium varied in direct relation to the concentration of glucose in the incubation medium and to the concentration of acetyl-CoA in the slices; the relation between the concentrations of acetyl-CoA and of acetylcholine in the slices was linear. It was concluded that the availability of acetyl-CoA had a decisive influence on both the rate of synthesis of acetylcholine and its steady-state concentration. The observations accord with the view that, at the ultimate level, the synthesis of acetylcholine is controlled by the Law of Mass Action.
D000105:Acetyl Coenzyme A / Q000378:metabolism*; D000109:Acetylcholine / Q000096:biosynthesis / Q000378:metabolism*; D000818:Animals; D002421:Caudate Nucleus / Q000187:drug effects / Q000378:metabolism*; D002794:Choline / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D066298:In Vitro Techniques; D010261:Paraoxon / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D051381:Rats
D000105:Acetyl Coenzyme A; D005947:Glucose; D002794:Choline; D000109:Acetylcholine; D010261:Paraoxon; D011188:Potassium