What happens to the electrochemical gradient for sodium when extracellular sodium concentration decreases?

When the extracellular sodium concentration decreases, the electrochemical gradient for sodium also decreases. The electrochemical gradient is determined by both the concentration gradient of sodium across the cell membrane and the electrical potential difference. Sodium ions naturally want to move down their concentration gradient from an area of high concentration (outside the cell) to lower concentration (inside the cell).

A decrease in extracellular sodium concentration reduces the concentration gradient, making it less favorable for sodium ions to move into the cell. As a result, the driving force for sodium ions to enter the cell diminishes, leading to a decrease in the overall electrochemical gradient. This alteration in the gradient can have significant implications for cellular processes, particularly in terms of action potential generation and overall cellular excitability.