Question

Billy was slipped a poison. This particular poison slows down the Na-K solute pump of neurons. If the solute pump slows down, what will happen to the neurons? Will the neurons become more excitable or less excitable or would it have no effect on depolarization potential?

Answer 1

The sodium potassium pump (NaK pump) is vital to numerous bodily processes, such as nerve cell signaling, heart contractions, and kidney functions. NaK pumps function to create a gradient between Na and K ions. It is responsible for movement of potassium ions into the cells while simultaneously moving the sodium ions outside the cell. The inhibition of the Na/K pump will allow Na ions to accumulate in the cell, as K ion will fall .

The larger part of the membrane potential is due to a relatively high membrane permeability to K+ (through K+ channels). K+ flows out of the cell because of the concentration gradient, but as it flows out, the inside of the cell become increasingly negative (positive ions leave) to an extent where the negative electrical potential draws K+ back into the cell at the same rate as it leaves due to the concentration gradient. This is the basis of the membrane potential, and it only exist because the sodium pump maintains the concentration gradients of Na and K. So over a longer period of time, inhibition of the sodium pump remove the concentration gradient and hence the membrane potential.

Neurons are electrically excitable, due to maintenance of voltage gradients across their membranes. If the voltage changes by a large enough amount over a short interval, the neuron generates an all-or-nothing electrochemical pulse called an action potential.

So as Na+-K+ pump slows down,The membrane potential is lost.So the neurons become less excitable.Neurons are excitable because of the presence Membrane potential.