热驯化对高山倭蛙体内氧化应激和抗氧化防御系统的影响

Effects of Thermal Acclimation on Oxidative Stress and Antioxidant Defense Systems in the Nanorana parkeri

以青藏高原特有两栖动物高山倭蛙(Nanorana parkeri)为研究对象,通过实验室内热驯化处理(26℃,以16℃为对照;2周),探究长期热驯化对其体内氧化应激水平和抗氧化防御系统的影响。结果显示:热驯化导致高山倭蛙骨骼肌中氧化型谷胱甘肽含量显著升高(t=1.4,df=10,p<0.001),肝脏和骨骼肌中氧化型与还原型谷胱甘肽比值显著上升,表明其体内氧化应激水平升高;组织中超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶和谷胱甘肽转移酶活性发生了特异性增加;肝脏丙二醛含量明显下降,骨骼肌丙二醛含量没有明显变化,表明热驯化并未导致氧化损伤指标增加,这得益于体内完善的抗氧化防御系统。研究结果有助于阐明全球气候变暖对青藏高原两栖动物的影响。

In this study,Nanorana parkeri,an amphibian endemic to the Tibetan Pla⁃teau,was treated with thermal acclimation at 26℃(16℃as the control)for two weeks in the laboratory to investigate the effects of long-term thermal acclimation on oxidative stress level and antioxidant defense system of N.parkeri.The results show that the content of oxidized glutathione in muscle tis⁃sues(t=1.4,df=10,p<0.001)and the ratio of oxidized to reduced glutathione in liver and muscle tissues were signifi⁃cantly increased due to the thermal acclimation,suggesting an enhanced oxidative stress.The activity of superoxide dis⁃mutase,catalase,glutathione peroxidase,and glutathione S-transferase showed a tissue-specific increase.Moreover,malondialdehyde content decreased significantly in the liver but did not change in muscle tissues,suggesting that thermal acclimation did not lead to an increase in the indicator of oxidative damage,which was attributed to a well-established anti⁃oxidant defense system.This study will help to elucidate the effects of global warming on the amphibians living on the Ti⁃betan Plateau.