The research of molecular and ionic mechanisms in vagally mediated atrial fibrillation in canine.
BACKGROUND
The reentrant mechanism of vagally mediated AF is not clearly elucidated.


RESULTS
After vagal stimulation, thirty dogs were divided AF group (AF could be induced) and control group (AF could not be induced). Western blot and patch clamp were used to determine M(2) receptor and I(K,ACh) in left atrial appendage (LAA), right atrial appendage (RAA), left atrium (LA), right atrium (RA), pulmonary veins (PVs) and superior vena cava (SVC). In control group, the densities of M(2) receptor and I(K,ACh) in LAA, RAA and LA were higher than that in RA, PVs and SVC. However, there was no significant difference in LAA, RAA and LA. In AF group, the densities of M(2) receptor and I(K,ACh) in LAA, RAA and LA were higher than that in RA, PVs and SVC. Furthermore, the densities of the M(2) and I(K,ACh) in LAA and RAA were higher than that in LA.


CONCLUSIONS
Atrial appendage perhaps play an important role in initiation of cholinergic AF. However, PVs and SVC less often play an important role in vagotonic paroxysmal AF.
Zhao
Qing-Yan
QY
Huang
Cong-Xin
CX
Jiang
Hong
H
Yang
Bo
B
Liang
Jin-Jun
JJ
Chen
Hui
H
Li
Geng-Shan
GS
D000818:Animals; D001281:Atrial Fibrillation / Q000209:etiology / Q000503:physiopathology*; D004285:Dogs; D004558:Electric Stimulation; D007477:Ions; D008967:Molecular Biology; D014630:Vagus Nerve
D007477:Ions