| 김유경¹, 황경국¹, 권진숙², 한아름¹, 정일하¹, 심태진¹, 박노관¹, 이원익¹, 배장환¹, 김동운¹, 조명찬¹ |
Objective: Cellular redox balance may play an important role in cardiac hypertrophy and its regression. We analyzed the redox status, expressions of redox regulating protein, thioredoxin(Trx) and peroxiredoxin(Prx) in the heart from pressure overload-induced cardiac hypertrophy, and the change of Trx and Prx during the regression of cardiac hypertrophy. Design and Methods: Pressure overaload-induced cardiac hypertrophy was obtained by controlled constriction of the transverse aorta(TAC) of Spraque-Dawley rat. Dynamic expressions of Trx, thioredoxin-interacting protein(Txnip), endogenous inhibitor of Trx, and thioredoxin reductase(TrxR) were evaluated by Western blot, and also mRNA of Prx-1, 2, 3, 4, 5 and 6 were evaluated by polymerase chain reaction in heart from cardiac hypertrophy by TAC(1,3,5days, 1,2weeks;n=10, 2/each time point) and regression by relieving constriction(serial time points of 1,3,5days, 1, 2weeks;n=10, 2/each time point). Results: Systolic blood pressure of TAC group was significantly increased after immediate consriction and persisted upto 2weeks(195.0±5.0 vs 110.9±10.2 mmHg,p<0.01). Anatomical change of LV hypertrophy in TAC group was observed at 2weeks(wall thickness:1.94±0.38 vs 1.28±0.13mm,p<0.05, LV mass/body weigh:2.69±0.31 vs 2.26±0.28mg/g,p<0.05). Expression of Trx/Txnip ratio was significantly increased from D1 till D3 (acute hypertensive stress period) and then decreased till 2 weeks (relatively adapted period). Expression of TrxR was more increased in TAC group till 1 week. mRNA of Prx-1, 2, 3, 4 and 5 were increased from D1 till D5 and then decreased till 2 weeks. Significant decrease of blood pressure (151.1±21.5 vs 117.2±20.1mmHg,p<0.01) at relieving TAC and regression of LVH was observed at 3days later(LV mass/body weight;2.69±0.31 vs 2.12±0.37mg/g,p<0.05). Immediately after relieving of constriction, the expression pattern of Trx, Txnip were reversed from D1(untying TAC). mRNA of Prx-1, 2, 3, 4 and 5 were increased immediately at D1(untying TAC) and then decreased till 2weeks. Theses findings suggest dynamic role of Trx, Txnip and Prx in hypertension and LVH. Conclusion: Trx and Prx may play a crucial role in the development and regression of hypertension and LVH
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