Austin So (Hae Jin) wrote in message <38175D80.96AC5698 at netinfo.ubc.ca>...
>Since no one but that guy ken collins replied...
Actually Ken Collin's reply, for once, was on topic and actually relevant!
>"leak" currents are due to things like transporters (in either direction,
and
>may or may not involve ATP) which generally co-transport ions through the
>membrane.
Since leak currents are responsible for electrotonic potentials, they are
directly proportional to the driving force. That is usually not the case
with transporters, especially the active ones involving ATP. Those usually
show saturation kinetics. The pumps, in particular, are controlled by other
factors and do not readily respond to changes in potential. And, besides,
the leaks continue in the absence of metabolic energy.
>And yes...ion channels do not "leak".
No, in the closed position they do not. But at resting potential some may
remain open and therefore be responsible for the "resting" or "leak"
permeability.
>Any good neurophysiology text should give you good information about them.
The specific reason I ask is that no good neurophysiology text gives the
information
I requested. Of course, they all describe the leak and they all describe in
detail
the molecular structure of the gated channels. And some have long lists of
varieties of gated channels. But NO text I checked indentifies specifically
what
ion channel is reponsible for the resting leak.
