Depolarizációja

Depolarizációja refers to the process of depolarization in a biological or electrochemical context. In neuroscience, it specifically describes the change in the electrical potential across the cell membrane of a neuron. Normally, a neuron maintains a negative charge inside relative to the outside, a state known as resting potential. During depolarization, positively charged ions, such as sodium (Na+), flow into the neuron, making the inside of the cell less negative and potentially triggering an action potential. This influx of positive charge reverses the membrane potential, making the inside momentarily positive compared to the outside.

This phenomenon is fundamental to nerve impulse transmission. When a neuron receives a sufficient stimulus, depolarization occurs at a specific point on its membrane. If this depolarization reaches a threshold level, it initiates an action potential, which is a rapid and transient electrical signal that propagates along the axon. Following depolarization, a repolarization phase occurs where the membrane potential returns to its resting state, often involving the outward flow of potassium (K+) ions. The term "depolarizációja" highlights the active shift away from the polarized resting state. In other contexts, depolarization can also refer to the loss of polarization in other types of cells or systems, but its most prominent application is in understanding neuronal communication.