Activation of extracellular-signal regulated kinase and protein phosphatases in human atria during atrial fibrillation / 中国病理生理杂志

ABSTRACT

AIM: The purpose of this study was to determine whether the signal transduction systems were activated at the molecular atrial tissue level in patients with atrial fibrillation (AF) and whether atrial expression of extracellular-signal regulated kinase (ERK) and protein phosphatases is altered. METHODS: Atrial tissue sample of 30 patients undergoing cardiac surgery were examined. 20 patients had AF, 10 patients had no history of AF. The mRNA expression of calcineurin B and MKP-1 were detected by semi-quantitative RT-PCR. ERK1 and phospho-ERK1 were analyzed at the protein level by Western blot. RESULTS: Western blot analysis showed that atrial fibrillation did not induce significant change in ERK1 expression level in the left atrium. In contrast , phospho-ERK1 content was increased in the patients with AF in comparison with those who had sinus rhythm (SR). The mRNA expression of calcineurin B and MKP-1 in the patients with AF were significantly higher than that in patients with SR. CONCLUSION: The activation of extracellular-signal regulated kinase and protein phosphatases may have correlation with the initiation or maintenance of atrial fibrillation.