Lei-Dab7 TFA, a selective and high-affinity blocker of the K Ca 2.2 (SK2) channel with a dissociation constant (K d) of 3.8 nM, demonstrates over 200-fold selectivity for K Ca 2.2 compared to K Ca 2.1, K Ca 2.3, K Ca 3.1, K v, and Kir2.1. Furthermore, Lei-Dab7 TFA enhances theta-burst responses and long-term potentiation (LTP) in rat hippocampal slices in vitro.