Study Of The Expression Of Heat Shock Protein 47 And Its Correlation To Myocardial Fibrosis In The Atrial Tissues With Atrial Fibrillation

Objective: Atrial fibrillation(AF) is a common clinically arrhythmia. Atrial remodeling and myocardial fibrosis play an improtant role in the genesis and maintenance in AF. Heat shock protein 47 (HSP47)is an cytokine,it recognized as the pro-collagen-specific chaperone protein and plays an improtant role in the process of collagen deposition and fibrosis. To study the expression of HSP47 in atrial tissues with Real-time Fluorescence Quantitative PCR(FQ-PCR) and its relevance to Pâ… CP, Pâ…¢NP,the indexs of myocardial fibrosis in blood-serum, and to explore the molecule mechanisms of structural atrial remodeling.Methods: The right atrial tissues and blood-serum samples were taken from 60 patients with cardiac surgery. 20 patients were in sinus rhythm. 20 patients had per sistent AF and 20 patients had paroxysmal AF. The mRNA amounts of HSP47 were studied by Real-time Fluorescence Quantitative PCR method,and the concentrati-ons of carboxyterminal propeptide of typeâ… procollagen(Pâ… CP) and amino-terminal prop eptide of typeâ…¢procollagen(Pâ…¢NP) in serum were measured by enzyme linkedimm unosorbent assay(ELISA).Results: (1)The mRNA level of HSP47 significantly increased in both paroxysmal AF and persistent AF groups compared with the sinus rhythm group(P<0.05, P<0.05). The significant increase in HSP47 was also observed in the persistent AF compared with paroxysmal AF groups(P<0.05). (2)Compared with controls, the concentrations of serum Pâ… CP, Pâ…¢NP and Left Atrial Diameter were significantly increased in patients with AF(P<0.05, P<0.05, P<0.05). The significant increase was also observed in the persistent AF compared with paroxysmal AF groups in the concentrations of serum Pâ… CP, Pâ…¢NP and left atrial diameter (P<0.05 P<0.05, P<0.05) .(3) There was a conspicuous and independent direct correlation between the expression of HSP47 and the Pâ… CP, Pâ…¢NP and Left Atrial Diameter (r=0.831,P <0.01; r=0.842, P <0.01; r=0.780, P <0.01) .Conclusions: There were myocardial fibrosis and left atrial enlargementin the persistents with atrial fibrillation. The HSP47 gene is highly expressed in right atrial tissues and closely correlated with the degree of the atrial fibrillation,it indicates that HSP47 gene related wi-th the genesis and maintenance of atrial fibrillation. The expression of HSP47 in right atrial tissues were correlated between Pâ… CP, Pâ…¢NP and Left Atrial Diameter and demonstrated that the increase in expression of HSP47may be one of the molecule mechanisms of myocardial fibrosis and closely related with structural atrial remodeling.