Table 3.
Functional properties of EAG K+ channels in heterologous expression systems
| Activation | Deactivation τdeact(msec) | Inactivation | Pharmacology (IC50) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Von(mV) | V1/2 (mV) | k(mV) | τfast (msec) | τslow(msec) | Cole–Moore shift | τinact(msec) | τrecov (msec) | TEA | 4-AP | E-4031 | ||
| Eag1 | −60 to −50 | −11.8 to −4.1 | 23.5 | 12 @ 40 mV3-a | 210 @ 40 mV3-a | y | 1–6 | No inactivation | 28 | NB by 20 mm | NB | |
| Eag2 | −100 | −35.5 | 29 | 14.6 @ 40 mV3-a | 202 @ 40 mV3-a | y | Fast | No inactivation | 19 @ 40 mV | NB by 20 mm | NB by 1 μm | |
| Erg1 | −60 to −50 | −21 | 6 to 8 | 200 @ 0 mV | n | Seconds @ −70 mV | 4.3 @ 30 mV | NA | Slows channel inactivation | NA | KD 99 nm | |
| Erg2 | −40 | −3.5 | 8.3 | 111 @ 0 mV | 500 @ 0 mV | n | Seconds @ −70 mV | 4.7 @ 30 mV | NA | NA | NA | KD 116 nM |
| Erg3 | −80 to −70 | −44 | 7.2 | 25 @ 0 mV | n | ∼100 @ −70 mV | 8 @ 30 mV | NA | NA | NA | KD193 nM | |
| Elk1 | −40 | 9.3 | 13.1 | 676 @ 0 mV | n | 111 @ −50 mV | No inactivation | NB by 10 mM | NB by 10 mM | NB by 10 μM | ||
| Elk2 | −80 to −70 | −6.4 to −24.4 | 20.1 to 28.3 | 7.7 @ 30 mV | 70.0 @ 30 mV | n | τfast = 93.7
τslow = 622 @ −50 mV |
10.2 @ 30 mV | 6.7 @ −50 mV | Slows channel inactivation | NA | NB by 10 μM |
| Elk3 | −90 | −59.1 | 10.8 | 38 @ 0 mV | 360 @ 0 mV | n | 201 @ −80 mV | No inactivation | NB by 100 mM | NB by 10 mM | NB by 10 μM | |
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Data were obtained from Ludwig et al. (1994),Robertson et al. (1996), Terlau et al. (1996), Shi et al. (1997, 1998), Bijlenga et al. (1998),Engeland et al. (1998), Frings et al. (1998), Saganich et al. (1999), Schonherr et al. (1999), and Trudeau et al. (1999).
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y, Yes; n, no; NA, not available; NB, not blocked;Von, “activation” voltage; time constants at room temperature.
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↵F3-a Holding potential = −90 mV.
