Martínez RM

Language: Spanish
References: 11
Page: 205-210
PDF size: 76.84 Kb.

ABSTRACT

The ionic channels are membrane proteins containing aqueous pores that permit ion flow through cell membranes. They are essential components in the activity of all kind of cells. They can be classified in function of stimulus necessary to open or shut the channel in: voltage-gated, ligand-gated and mechanosensitive channels. In mammals they play important roles like: nerve and muscle excitation, hormone and neurotransmitter secretion, sensory transduction, the control of water and electrolyte balance, regulation of blood pressure, cell proliferation and learning and memory process. By techniques of molecular biology and electrophysiology the genes that codify for the ionic channels have been cloned, expressed, and characterized. The recently proposed concept of “channelopathy” refers to the alterations in the structure-function of ion channels that could produce a variety of diseases in many tissues. This work reviews the basic concepts about ionic channels as functional proteins and the most of the channelopathies reported at date and focuses in the long QT syndrome, the Brugada syndrome and conduction system disease in the heart.

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