Voltage dependence of
gK activation. The circles correspond to the experiment illustrated in figure 1. The
Io results from those records were normalized by GHK[(
V−
EK)]. The values of that procedure reached saturation at +5 mV. The points at 5, 15, 25 and 35 mV were averaged, and that average value was used to normalize the results a second time so that this relation for
V≥5 mV corresponds to unity. The curve labelled ‘HH
’ represents
in the HH (1952d) model, where
n∞(
V)=
αn/(
αn+
βn). The curve labelled ‘
revised’ is the prediction of the model using the modified
βn described in the text (
Vo=19.7 mV as opposed to 80 mV in the HH model).