Hemicholinium-3

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Hemicholinium-3
Hemicholinium-3.svg
Hemicholinium-3 cation spacefill.png
Clinical data
Other names2-[4-[4-(2-hydroxy-4,4-dimethylmorpholin-4-ium-2-yl)phenyl]phenyl]-4,4-dimethylmorpholin-4-ium-2-ol
ATC code
  • None
Identifiers
  • (2S,2S)-2,2'-biphenyl-4,4'-diylbis(2-hydroxy-4,4-dimethylmorpholin-4-ium)
CAS Number
PubChem CID
IUPHAR/BPS
ChemSpider
UNII
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard 100.005.663 OOjs UI icon edit-ltr-progressive.svg
Chemical and physical data
Formula C24H34N2O42+
Molar mass 414.546 g·mol−1
3D model (JSmol)
  • [Br-].[Br-].OC1(OCC[N+](C)(C)C1)c2ccc(cc2)c3ccc(cc3)C4(O)OCC[N+](C)(C)C4
  • InChI=1S/C24H34N2O4.2BrH/c1-25(2)13-15-29-23(27,17-25)21-9-5-19(6-10-21)20-7-11-22(12-8-20)24(28)18-26(3,4)14-16-30-24;;/h5-12,27-28H,13-18H2,1-4H3;2*1H/q+2;;/p-2 Yes check.svgY
  • Key:OPYKHUMNFAMIBL-UHFFFAOYSA-L Yes check.svgY
 X mark.svgNYes check.svgY  (what is this?)    (verify)

Hemicholinium-3 (HC3), also known as hemicholine, is a drug which blocks the reuptake of choline by the high-affinity choline transporter (ChT; encoded in humans by the gene SLC5A7) at the presynapse. The reuptake of choline is the rate-limiting step in the synthesis of acetylcholine; hence, hemicholinium-3 decreases the synthesis of acetylcholine. It is therefore classified as an indirect acetylcholine antagonist. [1]

Contents

Acetylcholine is synthesized from choline and a donated acetyl group from acetyl-CoA, by the action of choline acetyltransferase (ChAT). Thus, decreasing the amount of choline available to a neuron will decrease the amount of acetylcholine produced. Neurons affected by hemicholinium-3 must rely on the transport of choline from the soma (cell body), rather than relying on reuptake of choline from the synaptic cleft.

Toxicity

Hemicholinium-3 is highly toxic because it interferes with cholinergic neurotransmission. The LD50 of hemicholinium-3 for mice is about 35 μg. [2]

See also

Related Research Articles

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References

  1. Carlson NR (2007). Physiology of Behavior (9th ed.). Boston: Pearson Education, Inc. p. 117. ISBN   978-0-205-46724-2.
  2. Freeman JJ, Kosh JW, Parrish JS (October 1982). "Peripheral toxicity of hemicholinium-3 in mice". British Journal of Pharmacology. 77 (2): 239–44. doi:10.1111/j.1476-5381.1982.tb09291.x. PMC   2044599 . PMID   7139185.