If a blocker prevents repolarization, will the neuron be stuck in a depolarized state forever?

Question

Potassium channels help to repolarize the cell after depolarization. But if the potassium channels are blocked, potassium ions cannot flow out of the cell to increase the membrane potential. Thus, one would expect that, at least for some period of time, the cell would be "stuck" in a depolarized state. \n\nHow long can this state last? Can a neuron go on indefinitely in a depolarized state if potassium ion channels are blocked? Will it find some other way to depolarize the cell? Will the cell die?

Answer 1

Great question. I think your answer actually stems down to the concept of the equilibrium state. People aren't computers, and things generally aren't binary (on/off), and it's why you see a spectrum of effect depending on how much concentration of the blocker you use in the lab, or how much we use in patients in clinical practice.

To answer your next question, I haven't ever really asked if the individual neuron's survival would be dependent on intracellular potassium, but since glucose transport is geared around diffusion and semi-active transport and sodium, my answer is probably not. In vitro, I could see how tweaking the potassium concentration could give you issues with fluid balance.

I do think that as an organism, you have much bigger fish to fry if you potassium channels blocked; that's your heart stops beating right!