- Chae, Y.J. et al. (2014) Neurosci. Lett. 578, 159.
- Alomone Labs Trifluoperazine dihydrochloride blocks KV4. 3 channels expressed in Xenopus oocytes.A. Time course of KV4.3 current amplitude and inhibition by 100 and 300 µM Trifluoperazine dihydrochloride (#T-175). Currents were elicited by application of voltage step from a holding potential of -80 mV to 0 mV (150 msec), every 10 seconds. B. Superimposed example traces of current responses before and during perfusion of 100 and 300 µM Trifluoperazine dihydrochloride, as indicated.
KV4 channel complexes also known as Shal-type K+ channels are expressed in a number of tissues, with particularly high levels in the brain and heart. These channels are the primary subunits that contribute to transient, voltage-dependent K+ currents in the nervous system and the heart1.
Trifluoperazine dihydrochloride is a synthetic high affinity KV4.3 blocker and is also an inhibitor of D1 and D2 dopamine receptors. Trifluoperazine dihydrochloride has an effective concentration of 5-300 μM with an IC50 of 8 μM on cloned KV4.3 channels. Trifluoperazine is hypothesized to block KV4.3 channel directly (and not through other protein mediation) and preferably in its open state. This is assumed due to findings showing Trifluoperazine decreasing peak amplitude of KV4.3 but at the same time accelerating the apparent inactivation rate and the time-to-peak of the channel. Trifluoperazine is a widely used substance for the management of schizophrenia and other mental illnesses. Its anti-psychotic therapeutic effect is achieved through the blocking of post-synaptic D2 receptors in dopaminergic neurons.