Hiperpolarizáló

Hiperpolarizáló refers to a phenomenon observed in certain biological systems, particularly in the nervous system, where a membrane potential is driven to a value significantly more negative than the resting membrane potential. This extreme hyperpolarization can be caused by the rapid efflux of potassium ions from the cell or the influx of chloride ions.

In neurons, hyperpolarization occurs after an action potential. The outward flow of potassium ions through voltage-gated channels, which are responsible for repolarizing the membrane, often continues briefly, leading to a brief period of hyperpolarization. This transient hyperpolarization is known as the afterhyperpolarization. It plays a role in regulating neuronal firing rates and can influence the timing of subsequent action potentials.

Certain neurotransmitters, like GABA and glycine, can also induce hyperpolarization when they bind to their respective receptors, which are often ligand-gated chloride channels. Activation of these channels allows chloride ions to flow into the neuron, making the inside of the cell more negative. This inhibitory effect makes it less likely for the neuron to reach its threshold for firing an action potential.

The term hiperpolarizáló is less commonly used in English-language scientific literature compared to "hyperpolarization." However, in contexts where the extreme nature of the negative shift in membrane potential is emphasized, or in specific theoretical discussions, the prefix "hiper-" (meaning "over" or "beyond") might be employed, particularly in languages other than English.