Jonsson G G, Menard L, Jacobson E L, Poirier G G, Jacobson M K
Department of Biochemistry, Texas College of Osteopathic Medicine, University of North Texas, Fort Worth 76107.
Cancer Res. 1988 Aug 1;48(15):4240-3.
The effects of supranormal temperature on the activity of poly(ADP-ribose) glycohydrolase were studied by assaying the enzyme in cell extracts derived from cells subjected to hyperthermia and comparing with extracts that were heated in vitro. The enzyme activity was reduced by both hyperthermic treatment of cells and by heating of cell extracts; however greater reductions were observed when intact cells were subjected to hyperthermia. The additional reduction observed when intact cells were heated was reversed when cells were allowed to recover at 37 degrees C following hyperthermia. We postulate that hyperthermia alters poly(ADP-ribose) glycohydrolase activity by two mechanisms, an irreversible thermal denaturation of the enzyme and a reversible metabolic alteration. Changes in poly(ADP-ribose) glycohydrolase activity can account in full for the observed alterations of poly(ADP-ribose) metabolism that occur following hyperthermia.
通过检测来自热疗细胞的细胞提取物中的聚（ADP - 核糖）糖苷水解酶活性，并与体外加热的提取物进行比较，研究了超正常温度对聚（ADP - 核糖）糖苷水解酶活性的影响。热疗处理细胞和加热细胞提取物均会降低该酶的活性；然而，当完整细胞接受热疗时，观察到的活性降低幅度更大。当完整细胞受热后在37摄氏度恢复时，观察到的额外活性降低得以逆转。我们推测，热疗通过两种机制改变聚（ADP - 核糖）糖苷水解酶的活性，一种是酶的不可逆热变性，另一种是可逆的代谢改变。聚（ADP - 核糖）糖苷水解酶活性的变化可以完全解释热疗后观察到的聚（ADP - 核糖）代谢改变。
