Hemicholinium-3
（重定向自Hemicholinium）
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.