Previous observations reported by our group indicate that 2.45 GHz microwave fields at specific absorption rate (SAR) of 5.6 W/kg reduce the enzyme activity rate of ascorbate oxidase (AO) trapped in liposomes. In this study, we report dose-response studies on these AO containing liposomes irradiated at different SAR values (1.4, 2.8, 4.2, and 5.6 W/kg). No response was observed for SAR below 5.6 W/kg. Liposomes entrapping functional AO in its deglycated form (AO-D) were also used. In this case, no MW related enzyme activity changes were observed, demonstrating a direct involvement of oligosaccharide chains of AO. Furthermore, the catalytic properties of both AO and AO-D were not impaired by MW irradiation, neither in homogeneous solution nor loaded in liposomes, excluding possible changes in the conformation of enzyme as a mechanism. Our results suggest that the oligosaccharide chains of AO are critical to elicit the microwave observed effects on lipid membrane. Bioelectromagnetics 25:338-345, 2004.
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机译：我们小组先前报告的观察结果表明，比吸收率 （SAR） 为 5.6 W/kg 的 2.45 GHz 微波场降低了脂质体中捕获的抗坏血酸氧化酶 （AO） 的酶活性率。在这项研究中，我们报告了在不同 SAR 值（1.4、2.8、4.2 和 5.6 W/kg）下照射的这些含有脂质体的 AO 的剂量反应研究。在低于 5.6 W/kg 的 SAR 下未观察到反应。还使用了以脱糖形式 （AO-D） 捕获功能性 AO 的脂质体。在这种情况下，没有观察到MW相关的酶活性变化，表明AO的寡糖链直接参与。此外，AO和AO-D的催化性能都没有受到MW辐照的损害，无论是在均相溶液中还是在脂质体中，排除了酶构象的可能变化。我们的结果表明，AO的低聚糖链对于引发微波观察到的脂质膜效应至关重要。生物电磁学 25：338-345， 2004.
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