Brain Phosphatidylcholine Pools as Possible Sources of Free Choline for Acetylcholine Synthesis

Treatment with Oxiracetam or Choline Restores Cholinergic Biochemical and Pharmacological Activities in Striata of Decorticated Rats

“…The data taken together indicate that Ch most likely acts directly simply by being the precursor for ACh, whereas OX1 appears to act indirectly, possibly by increasing the availability of Ch for ACh synthesis. In accordance with this hypothesis is the finding (Trovarelli et al, 1986) that OX1 improves the in vitro and in vivo synthesis of phospholipids impaired by aging, and in particular, the phosphatidylcholine pool proposed as a "reservoir" to generate choline for the synthesis of ACh Lakher et al, 1986). Interestingly, it was reported that ACh can be synthesized from Ch derived from the breakdown of endogenous phosphatidylcholine formed de novo by the stepwise methylation of phosphatidylethanolamine .…”

“…In accordance with this is the finding that, in striatum of DC rats, the transmethylation pathway is enhanced (Tacconi et al, 1988), possibly to sustain the striatal cholinergic activity depressed by the lesion. However, whether the effect of OX1 occurs in the transmethylation pathway or in others known to exist in the brain Lakher et al, 1986), e.g., CDP-choline and the base exchange pathways, needs to be clarified.…”

Cerebral phosphoester signals measured by 31P magnetic resonance spectroscopy at 3 and 7 Tesla

“…The choline singlet at 3.2 ppm observed in the proton MRS spectrum of healthy volunteers originates almost entirely from the trimethylamine group of PC and GPC [ 10 , 25 ], given that the concentrations of choline, acetylcholine, and phosphatidylcholine in their free forms are negligibly low at the sensitivity level of proton MRS [ 26 – 28 ]. That is, where tCho is total choline.…”