What effect does Cajal cell repolarization have on potassium?

Cajal cells, which are specialized interstitial cells found in the gastrointestinal tract, play a crucial role in regulating the rhythmic contractions of smooth muscle. During their repolarization phase, the movement of potassium ions is particularly significant.

Repolarization refers to the process of restoring a cell's membrane potential after depolarization, which is often triggered by an influx of ions such as sodium during an action potential. As the cell returns to its resting state, potassium ions diffuse out of the cell. This movement occurs because the cell membrane becomes more permeable to potassium, allowing it to leave the intracellular environment and enter the extracellular space.

This efflux of potassium is essential in stabilizing the membrane potential and contributing to the overall mechanism of muscle contraction and relaxation control in the gut. By releasing potassium, the Cajal cells help maintain the resting potential of the cell membrane, ensuring efficient transmission of signals for proper gut motility. This is why the correct answer highlights that potassium is released from the cell during repolarization.