【摘要】 目的 :观察钙超载大鼠心肌肌浆网 (SR )功能的变化。方法 :腹腔注射维生素D3和nicotine灌胃复制大鼠心肌钙超载模型。差速离心制备心肌肌浆网 ,微孔过滤技术测定SR的钙释放与钙摄取 ,放射配基法测定SRryanodine受体结合能力。结果 :钙超载大鼠心肌钙含量比对照组高 32 4% (P <0 0 1) ,心肌SR钙摄取和钙释放分别低 6 4%和 40 % (P <0 0 1)。心肌SRCa2 + -ATP酶活性低 6 5 % (P <0 0 1)。SR特异 [3H]-ryanodine结合的最大值Bmax低 5 1% (P <0 0 1)。结论 :钙超载大鼠心肌SR功能下降。更多还原

【Abstract】 AIM:To study alterations of cardiac sarcoplasmic reticulum (SR) function in vitamin D 3-induced calcium overload rats. METHODS: The Ca-overload rat models were prepared by vitamin D 3 plus nicotine. Cardiac SR was seperated by centrifuging. The measurement of SR Ca 2+ uptake and Ca 2+ release activities were preformed by the Millimore filtration technique. Specific SR [ 3H]-ryanodine binding capacity was measured by radioligand method. RESULTS: Compared with control,myocardial calcium content in calcium overload rats increased by 78%( P< 0.01), SR Ca 2+ uptake and Ca 2+ release activities decreased by 64% and 40% respectively( P< 0.01),and in the meantime ,the Ca 2+ -ATPase activity decreased by 65%( P< 0.01).Maxmum value for [ 3H]-ryanodine binding decreased by 51%( P< 0.01). CONCLUSION: The function of cardiac SR in calcium-overload rats was decreased.更多还原