When the brain is deprived of oxygen, the mitochondria within neurons cease producing ATP. What effect would this have on the membrane potential? Why?

Sourav PanSeptember 23, 2024

Answered

When the brain is deprived of oxygen, the mitochondria within neurons stop producing ATP, which has several critical effects on the membrane potential:

1. Inhibition of Ion Pumps: The sodium-potassium pump (Na⁺/K⁺ ATPase) relies on ATP to function effectively. This pump actively transports Na⁺ out of the cell and K⁺ into the cell, maintaining the ionic concentration gradients essential for the resting membrane potential. Without ATP, the pump cannot operate, leading to an accumulation of Na⁺ inside the cell and a depletion of K⁺.
2. Disruption of Concentration Gradients: As Na⁺ accumulates and K⁺ levels decrease, the normal concentration gradients across the membrane are disrupted. The inside of the cell becomes less negative, causing a shift in the membrane potential towards a more depolarized state.
3. Potential for Cellular Excitability: With the resting membrane potential becoming less negative, neurons may become more excitable and prone to spontaneous action potentials. However, prolonged depolarization can lead to cellular dysfunction and eventually cell death.