Remodeling Of Gap-junctional Proteins, Connexin40 And Connexin43, In Human Valvular Permanent Atrial Fibrillation.

Atrial Fibrillation(AF) is currently the most common sustained clinical arrhythmia. The prevalence of AF is estimated at 0.4% of the general population and is increasing with age. It occurs in more than 6% of those over 80 years of age and should responsible for increasing thromboemboli mortality rate.However, the completely electrophysiological mechanisms of AF remain unclear, and are principally based on traditional single cell membrane channels, and lessconcern on current conduction between cells. In fact, all of myocardium is involved in any type ofarrhythmia (including AF); arrhythmia is no fewer determined by passive current conduction than membrane channels. Accounting for AF is incomplete regardless of passive current conduction between cells. It has been proved that Gap-junction is the only structure responsible for intercellular current conduction.Gap junction is a specialized regions of the membranes of adjacent cells containing arrays of densely packed intercellular channels that directly connect the cytoplasmic compartments of neighboring cells and permit intercellular passage of ions and small molecules. Single gap junction channel is composed of six connexin that abbreviate CX by the molecular weight of the specific protein. It has been established that mammalian cardiac myocytes express CX43, CX40, and CX45. but different tissue of the heart express different amounts and combinations of these connexins, CX43 was confirmed to be abundantly expressed in all four chambers in human heart, CX45 expression appears to be concentrated within the atrioventricular conduction system and CX40 expression is more restricted in atrial. No CX40 expression was detected in adult human...