The ambient GABA in the cerebral spinal fluid is estimated to be 0.8 2.9 µM [23], a concentration that may produce tonic neuronal inhibition by activating slowly-desensitizing extrasynaptic high-affinity GABAARs [24].
Specifically, in contrast to other voltage-gated channels, HCN channels activate slowly in response to membrane hyperpolarization despite similar voltage-sensor movement [7], [8].
For example, effects we observed might be due the persistent sodium current that would activate slowly with spiking and persistently keep the cell above the firing threshold for an extended period after the current injection is removed.
Kv2 channels are activated slowly after large membrane depolarisations and therefore do not generally affect spike thresholds.
For instance, Schlau-Cohen discovered that one of the proteins she's interested in has two ways of handling light one that activates quickly in response to fast-moving clouds or shadows, and another that activates slowly during sunrise or sunset.
We find that the mass kinetics of different subpopulations are self-similar and are represented by the S-shaped Gompertz model of population growth, which reveals that smaller diameter CNTs activate more slowly but have longer catalytic lifetimes.
Furthermore, tooltips are displayed in the right bottom area of the GUI which are activated by slowly moving the mouse pointer over the various buttons, thus facilitating use of the applet.
In the same time scale, the starfish eggs were activated more slowly but displayed a similar pattern of spike formation in the perivitelline space (Fig. 9A).
In addition, AMPK, which was activated in slowly proliferating SCD1-deficient cells, is known to upregulate glucose uptake and glycolysis [25].
Both of these measures are consistent with Ih carried by HCN4 channels, which tend to activate more slowly and have a slightly more negative V1/2 than currents carried by HCN1-3 [29].
One can clearly see that Fyn and ZAP-70 were activated more slowly.
