RE: resting potential and K+ [HAPP-L]

["Pat Bowne" <Pat.Bowne@xxxxxxxxxxx>]

Alan Magid wrote:

In thinking about these matters, IGNORE any changes in the bulk
concentrations of the ions. They hardly change and so the reasoning in your
last paragraph is unrealistic. The ion movements are trivial, requiring only
the miniscule quantities of charge to change the charge on the membrane
capacitance.

But muscle firing, as in seizures or heavy exercise, is given as a cause of hyperkalemia. So surely the amount of K+ crossing the cell membrane is not always negligible.

Related to this, here's a question one of my ex-students just sent me. Any insights?

"If one of the principals of a general anesthetic drug like ether is to open K+ channels wider than usual in order to prevent most action potentials, is this a contributing factor to why patients are infused with intravenous solutions containing K+, in order to introduce suffient amounts of K+ back into the system so that the NA+/K+ pumps can get the K+ back into nerve cells?"

Pat


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