慢性低氧后钙转运的变化(英文)

目的 :本文研究大鼠慢性低氧后心肌钙转运的变化。方法 :将大鼠放置于 10 %氧环境下 4周 ,分离正常及慢性缺氧大鼠的右心室肌细胞 ,用光谱荧光法测定电刺激和咖啡因引起的细胞内 [Ca2 + ]i瞬变 ,并测定肌浆网膜上的Ca2 + ATP酶 （SERCA）和ryanodine受体 （RyR）蛋白的水平。结果 :低氧后电刺激和咖啡因引起的细胞内 [Ca2 + ]i瞬变的幅度降低且时程延长 ,RyR水平无明显改变但SERCA已显著减少。结论 :Ca2 + ATP酶活性和蛋白水平的降低是低氧钙转运异常的主要原因。

The changes of calcium homeostasis in rat cardiomyocytes following chronic hypoxia

AIM: To determine Ca_2 handling in the hearts of rats subjected to chronic hypoxia (CH). METHODS: Spectrofluorometry was used to measure intracellular Ca_2 concentration ([Ca_2 ] i ) and its responses to electrical stimulation and caffeine in myocytes from the right ventricles of the rats breathing 10% oxygen for 28 days and the age-matched control. The protein expression of sarcoplasmic reticulum Ca_2 -ATPase (SERCA) and its ryanodine receptor (RyR) were measured. RESULTS: It was found that the amplitude was decreased and the duration was prolonged for electrically induced calcium transient and caffeine induced calcium transient. Further study showed that SERCA expression was suppressed by CH while RyR expression did not alter. CONCLUSION: The results indicate that the attenuated Ca_2 -ATPase is mainly responsible for impaired Ca_2 handling in CH.