低温胁迫对东北林蛙雄性成体GP、PEPCK比活性的影响

Effect of Low Temperature Stress on Enzyme Specific Activity of GP and PEPCK in Male Rana dybowskii

采用葡萄糖氧化酶-过氧化物酶法、蒽酮比色定糖法分别检测低温胁迫下东北林蛙血糖和肝糖原、肌糖原的含量,并通过6-磷酸葡萄糖脱氢酶偶联比色法、乳酸脱氢酶偶联比色法分别检测低温胁迫下东北林蛙肝脏、肌肉糖原磷酸化酶(Glycogen phosphorylase,GP)和肝脏、肾脏磷酸烯醇式丙酮酸羧激酶(PEPCK)的比活性,以探讨低温对东北林蛙GP、PEPCK比活性的影响。结果表明:随着环境温度降低,东北林蛙血糖水平逐步升高,糖原含量逐步降低,与对照组相比,各低温组血糖升高极显著(P<0.01),而肝糖原和肌糖原含量降低极显著(P<0.01);与对照组相比,0℃组、-1℃组肝脏、肌肉组织GP比活性升高极显著(P<0.01),且肝脏、肾脏PEPCK比活性升高极显著(P<0.01)。说明低温胁迫促使东北林蛙糖原含量降低,糖原分解和糖异生限速酶比活性升高,进而血糖含量升高,提示血糖作为抗冻保护剂在东北林蛙冬眠中发挥重要作用。

The present study was aimed to investigate effect of low temperature stress on the enzyme specific activity of GP and PEPCK of Rana dybowskii.The impact of low temperature on the glucose,liver glycogen,muscle glycogen content of Rana dybowskii was determined and the impact of low temperature on the activities of GP,PEPCK of Rana dybowskiiwas also tested.Results showed that glucose contents in 4 ℃,0 ℃ and-1 ℃ groups were significantly increased（P0.01） compared with those in 23 ℃ group.Glycogen,muscle glycogen contents in 4 ℃,0 ℃ and-1 ℃ groups were significantly decreased（P0.01） compared with those in 23 ℃ group.Liver and muscle GP activities in 0 ℃ and-1 ℃ groups were observably increased（P0.01） compared with those in 23 ℃ group.Liver and kidney PEPCK activities in 0 ℃ and-1 ℃ groups were observably higher（P0.01） than those in 23 ℃ group.These results suggested that glucose played a role under low temperature in hibernate Rana dybowskii.