Expression of mortalin in patients with chronic atrial fibrillation.
BACKGROUND
In myocardium of patients with chronic atrial fibrillation (AF) the expression of the mitochondrial heat shock proteins HSP60 and HSP10 is increased. They are responsible for folding and translocation of proteins inside the mitochondria. Import of these proteins is accomplished by mortalin. The aim of our study was to investigate if the expression of the heat shock protein mortalin is also increased in patients with AF.


METHODS
Right atrial samples from 18 patients undergoing elective cardiac surgery were excised and immediately frozen in liquid nitrogen: 8 patients had chronic AF (> or = 3 month) and 10 patients were in sinus rhythm (SR). Mortalin was determined by SDS-PAGE, Western blot and quantified by optical densitometry.


RESULTS
In myocardial samples from patients with chronic AF we found a more than 2-fold increase in mortalin expression.


CONCLUSIONS
The increased expression of mortalin may represent an adaptive heat shock response to restore cellular homeostasis.
Department of Cardiac Surgery, University of Ulm, Steinhövelstr. 9, 89075 Ulm, Germany.
Kiriakos
K
Kirmanoglou
Andreas
A
Hannekum
Alfons E
AE
Schäfler
D000368:Aged; D001281:Atrial Fibrillation / Q000378:metabolism*; D002908:Chronic Disease; D001026:Coronary Artery Bypass; D005260:Female; D005786:Gene Expression Regulation; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D024101:Mitochondrial Proteins; D009206:Myocardium / Q000378:metabolism*
D018840:HSP70 Heat-Shock Proteins; C492001:HSPA9 protein, human; D024101:Mitochondrial Proteins; C080352:mortalin