We investigated the impacts of carbon dioxide (CO2)-induced acidification on energy metabolism in muscle tissue of rainbow trout Oncorhynchus mykiss fry. Fry were exposed to freshwater in equilibrium with air containing CO2 at volume concentrations of 380, 1000 and 2000 ppm for 30 days. At this critical and sensitive life stage, we showed dose-dependent reductions in weight gain and changes in energy metabolism under projected future CO2 levels. Rainbow trout fry exposed to elevated CO2 concentrations produced more energy in muscle tissue because ATP levels were significantly elevated. Fry exposed to 1000 ppm CO2 had a higher activity of pyruvate kinase (PK), higher concentrations of pyruvate, acetate, 2-oxoglutarate, phenylalanine, tyrosine, inosine, uracil and uridine, and lower concentrations of anserine and IMP in muscle tissue based on metabolomic analysis. We infer that the increased ATP production in fry exposed to 1000 ppm CO2 is produced through glycolysis. In the 2000 ppm group, the protein content of muscle was lower than in the control, and the activities of PK, cytochrome C oxidase (COX), Na+/K+-ATP and Ca2+/Mg2+-ATPase were significantly higher. Concentrations of pyruvate, 2-oxoglutarate, histidine, anserine and IMP were significantly lower, and alanine, methionine, leucine, isoleucine, valine, lysine, pantothenate, uracil and inosine were significantly higher. Accelerated tissue decomposition may have sustained the higher production of ATP in the 2000 ppm group.

中文翻译：

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基于代谢组学的虹鳟鱼Onkihynchus mykiss鱼苗肌肉组织中的能量代谢对CO2诱导的水生酸化的响应。

我们调查了二氧化碳（CO2）诱导的酸化对虹鳟Oncorhynchus mykiss鱼苗肌肉组织能量代谢的影响。将鱼苗暴露于与体积浓度分别为380、1000和2000 ppm的CO2的空气平衡的淡水中30天。在这个关键而敏感的生命阶段，我们显示出在预期的未来CO2水平下，体重增加的剂量依赖性降低以及能量代谢的变化。虹鳟鱼苗暴露于较高的CO2浓度会在肌肉组织中产生更多的能量，因为ATP含量显着升高。暴露于1000 ppm CO2的鱼苗具有较高的丙酮酸激酶（PK）活性，较高的丙酮酸，乙酸盐，2-氧戊二酸，苯丙氨酸，酪氨酸，肌苷，尿嘧啶和尿苷浓度，根据代谢组学分析，降低肌肉组织中的鹅肌苷和IMP浓度。我们推断，暴露于1000 ppm CO2的鱼苗中ATP产生的增加是通过糖酵解产生的。在2000 ppm组中，肌肉的蛋白质含量低于对照组，而PK，细胞色素C氧化酶（COX），Na + / K + -ATP和Ca2 + / Mg2 + -ATPase的活性显着较高。丙酮酸，2-氧戊二酸，组氨酸，鹅肌氨酸和IMP的浓度显着降低，丙氨酸，蛋氨酸，亮氨酸，异亮氨酸，缬氨酸，赖氨酸，泛酸，尿嘧啶和肌苷的浓度显着升高。加速的组织分解可能在2000 ppm组中维持了较高的ATP产生。在2000 ppm组中，肌肉的蛋白质含量低于对照组，而PK，细胞色素C氧化酶（COX），Na + / K + -ATP和Ca2 + / Mg2 + -ATPase的活性显着较高。丙酮酸，2-氧戊二酸，组氨酸，鹅肌氨酸和IMP的浓度显着降低，丙氨酸，蛋氨酸，亮氨酸，异亮氨酸，缬氨酸，赖氨酸，泛酸，尿嘧啶和肌苷的浓度显着升高。加速的组织分解可能在2000 ppm组中维持了较高的ATP产生。在2000 ppm组中，肌肉的蛋白质含量低于对照组，而PK，细胞色素C氧化酶（COX），Na + / K + -ATP和Ca2 + / Mg2 + -ATPase的活性显着较高。丙酮酸，2-氧戊二酸，组氨酸，鹅肌氨酸和IMP的浓度显着降低，丙氨酸，蛋氨酸，亮氨酸，异亮氨酸，缬氨酸，赖氨酸，泛酸，尿嘧啶和肌苷的浓度显着升高。加速的组织分解可能在2000 ppm组中维持了较高的ATP产生。泛酸，尿嘧啶和肌苷明显增高。加速的组织分解可能在2000 ppm组中维持了较高的ATP产生。泛酸，尿嘧啶和肌苷明显增高。加速的组织分解可能在2000 ppm组中维持了较高的ATP产生。