IC50: 19.9 μM (K ⁺ channel)

Quinidine hydrochloride monohydrate blocks WT mSlo3 (K _Ca 5.1) channels with an IC ₅₀ of 19.9±1.41?μM and Hill slope of 1.15±0.15 (n=7). Again, the potency of inhibition by Quinidine hydrochloride monohydrate is higher for F304Y mSlo3 (IC ₅₀ of 2.42±0.60?μM, n=9, P<0.005; Hill slope of 0.98±0.12), but lower with R196Q mSlo3 (IC ₅₀ of 38.4±6.77?μM, n=5, P<0.001; Hill slope of 1.05±0.16). The inhibition of F304Y mSlo3 by Quinidine hydrochloride monohydrate is observed to have some time dependence.

Direct application of Quinidine hydrochloride monohydrate on the sciatic nerve produces a dose-related decrease in amplitude at ascending somato-sensory evoked potential (SSEP) and descending compound muscle action potentials (CMAP) when comparing baseline with other time points, or when comparing the experimental left limb to the right contra-lateral glucose-treated limb. The latencies of SSEPs and CMAP potentials after Quinidine hydrochloride monohydrate applications are increased compare to baseline and the contralateral side.