N-[1-(phenylmethyl)-4(1H)-quinolinylidene]-1-pentanamine hydrochloride

CP 339818 hydrochloride is a nonpeptide and selective Kv1.3 (IC50 value of ~200 nM) and Kv1.4 channels blocker. CP 339818 hydrochloride is a significantly less potent blocker of Kv1.1, Kv1.2, Kv1.5, Kv1.6, Kv3.1-4, and Kv4.2. CP 339818 hydrochloride potently blocks the C-type inactivated conformation of Kv1.3 and suppresses T cell activation[1].

CP-338818 blocks both Kv1.3 and Kv1.4. Kv1.3 is expressed in brain and in effector memory T (Tem) cells, and Kv1.4 is expressed in brain cells. Kv1.3 and Kv1.4 are members of the Shaker family of voltage-gated potassium channels. Both channels are involved in setting the membrane potential of neurons. In addition, Kv1.3 maintains the membrane potential for T memory cells and is up-regulated upon T cell activation, contributing to multiple immune processes and disorders. Blockers of Kv1.3 have long been sought for therapeutic benefit, and they are also valuable tools for studying the immune system. CP-339818 is valuable for immune system studies, where the absence of Kv1.4 makes it functionally selective for Kv1.3, and it has shown suppression of T cell activation. CP-339818 is also valuable for the study of Kv1.4 function.

Kv1.3: 200 nM (IC₅₀); Kv1.4

[1] A Nguyen, et al. Novel nonpeptide agents potently block the C-type inactivated conformation of Kv1.3 and suppress T cell activation. Mol Pharmacol. 1996 Dec;50(6):1672-9. PMID:8967992