There are some evidence that other mechanisms might also be involved in enhancement in the excitability of CA1 pyramidal neurons, such as big conductance Ca++ -gated K+ channel (BK) activity and H channels. Calcium-activated potassium channels play an important role in regulating neuronal excitability, firing patterns, burst activity and neurosecretory pathway of neurons. De Rubeis and Colleagues showed a mutation of the ? subunit of the BK channel leads to enhancement of potassium conductance and then increased excitability. The mechanism underlies the increase BK current is rapid repolarization of action potentials and then faster removal of the inactivation state of sodium channels and therefor create neural hyperexcitability