p53-Bcl-2/Bax apoptosis signal pathway plays a key role in left ventricular remodeling of spontaneously hypertensive rats
Objective To reveal the underlying mechanism of left heart ventricular remodeling in spontaneously hypertensive rats through observing dynamic changes of the left ventricular pathological morphology,myocardial appoptosis,and proteins expressions of p53,Bcl-2 and Bax.Methods Male spontaneously hypertensive rats (SHR) and wistar-kyoto rats (WKY) at 13th week of age were adaptive fed for 1 week,then randomly divided into six groups.Rats in each group were fed to 18th,22th and 26th week-age (n =4) and left heart tissues were collected,respectively.During the period,rat tail blood pressure was tested by the Scientific CODA Kent method once four weeks,and the left ventricular tissue was taken to observe the changes of the pathological morphology and myocardial appoptosis via HE and TUNEL staining,respectively.The left ventricular tissue protein levels of p53,Bcl-2 and Bax were performed by western blot assay.Age-matched WKY were conducted as the normal control group.Results The above indexes of rats in WKY group had no significant changes as the increase of week-age.Compared with the age-matched WKY group,systolic blood pressure and diastolic pressure in rats of SHR group were increased.Left ventricular pathological remodeling and the apoptosis of cadiomyocytes were observed in rats of SHR group.The protein levels of p53 and Bax were increased,while the protein level of Bcl-2 and the ratio of Bcl-2/Bax were decreased.Compared with that of SHR 18 week-age group,the protein expression of Bcl-2 and the ratio of Bcl-2/Bax were reduced,other proteins expression of rats in SHR22 week-age and SHR 26 week-age group were increased.In addition,left ventricular pathological remodeling and the apoptosis of cadiomyocytes became more obvious.Compared with the SHR 22 week-age group,the above indexes of rats in SHR 26 week-age were aggravated.Conclusion The degree of left ventricular remodeling and apoptosis of cadiomyocytes,protein expressions of p53,Bcl-2 and Bax of rats in SHR are closely related to age,suggesting that p53-Bcl-2/Bax signal pathway-induced apoptosis is involved in left ventricular remodeling.
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NSTL
万方数据
维普
