Table 2.

Pharmacology of the cloned IK channel blockers.

Compound	IC50	hlK (hKCa3.1)
Charybdotoxin (CTX)	[nM]	2 [19], 2.5 [21], 3b [256], 3.3 [257], 10 [20], 28 [64]
CTX-Glu32	[nM]	33b[256]
Maurotoxin	[nM]	0.81 [257], 1.1a [246], 1.4 [246]
Margatoxin (MgTX)	[nM]	50 [7], 459 [64], > 100 [20]
Orthochirus toxin (OSK1)	[nM]	225 [258]
Stichodactyla toxin (ShK)	[nM]	291 [64], 30b [256, 259]
Bunodosoma toxin (BgK)	[nM]	172 [259]
Clotrimazole	[nM]	24.8 [21], 70b [256], 70–85 [260], 153 [64], 387 [20],
Econazole	[µM]	2.4 [64], 10 [260], 12b [256]
Ketoconazole	[µM]	30b[256],35[260]
Miconazole	[µM]	0.785 [64]
Nifedipine	[µM]	4b[256], 1.5[64]
Nimodipine	[µM]	lb [256]
Nitrendipine	[µM]	0.9b [256], 0.027 [64]
Verapamil	[µM]	72 [64]
Diltiazem	[µM]	154 [64]
Cetiedil	[µM]	79 [64]
TEA	[mM]	24b[256],30[20]
Tram-3C	[nM]	520 [260]
Tram-34	[nM]	20b[256, 261], 310d[250]
Tram-39	[nM]	60 [260]
Promethazine	[µM]	9.3e [262], 49 [262]
Enhancers
Compound	EC50	hlK (hKCa3.l)
1-EBIO	µM	74 [64], 84 [67, 71], 28.4 [66], 67d [250], 136 [193, 250]
Dichloro-EBIO (DCEBIO)	µM	0.84 [71], 2 [250], 4d [250]
NS309	nM	10 [73], 27 [7], 30 [250], 90d [250]
CyPPA	µM	>10 (inactive [74])
Chlorzoxazone	µM	98 [67]
GW275919X	µM	7d [250]
CCI7950	µM	0.07 [250]; 0.25d [250]

Reported are IC₅₀ values obtained from electrophysiological recordings and rubidium flux assays.

^a Rubidium flux measurements.

^b amino-terminal GFP-tagged channel was expressed.

^c TRAM, triarylmethane.

^d Results obtained by planar array electrophysiology (population patch [250]).

^e Applied to the in-side of a patch.