pH-Sensitive KV Channel Antibody Explorer Kit

K_V1.2 and K_V1.5 are pH sensitive. K_V1.5 currents are highly sensitive to acidic pH and decrease in amplitude by 46% at pH 6.3 and 96% at pH 5.3 when compared to current amplitude at pH 7.3. In contrary, K_V1.2 current amplitudes are relatively insensitive to an increase in proton concentration and only decrease by 3% at pH 6.3 and 17% at pH 5.3 when compared to currents at pH 7.3. Alkaline pH slightly increases K_V1.5 current amplitudes but does not seem to affect K_V1.2 current amplitudes. It is hypothesized that the reduction of K_V1.5 currents at pH 6.3 is caused by the accumulation of K_V1.5 wild-type channels in the C-type inactivated state. External acidification slows the recovery of K_V1.5 channels from inactivation by shifting the voltage dependence of activation of K_V1.5 to more depolarized voltages and increasing the time required to reach maximum current amplitude in response to depolarization. External acidification has little apparent effect on the rate of K_V1.2 recovery from inactivation.

The K_V1.3 channel is also pH-sensitive and its properties are altered by acidic pH. Current amplitude and magnitude of inactivation of K_V1.3 is reduced by acidic extracellular pH, an affect hypothesized to be induced by protonation of a histidine residue located near the channel’s pore¹.

Other K_V channels like K_V1.4 and K_V11.1 are also known to be pH-sensitive.