Research Area: Neurological Disease Biological Activity: Chlorpromazine (Sonazine) is a dopamine and potassium channel inhibitor with IC50 of 6.1 and 16 µM for nward-rectifying K+ currents and time-independent outward currents.In inhibits prolactin release inhibitory factor, thus stimulating the release of prolactin. The turnover of dopamine in the brain is also increased. [1] Chlorpromazine blocks a variety of K+ channels in heart muscle cells. Inasmuch as the potency of inhibition is less than the previously reported use-dependent block of Na+ channels, the cardiovascular adverse effects of chlorpromazine are probably caused mainly by the latter effect. [2]