Figure 6.

TEA⁺ prevents refilling of the pore by internal K⁺. (A) During normal function K channels close with K⁺ bound to a site within the pore. (B) TEA⁺ prevents refilling of the pore by intracellular K⁺ and, in the absence of extracellular K⁺, results in dekalification and loss of channel function.