Department of Biology, Laurentian University, Sudbury, Ontario, P3E 2C6, Canada.
Comp Biochem Physiol B Biochem Mol Biol. 2013 Oct;166(2):141-7. doi: 10.1016/j.cbpb.2013.08.002. Epub 2013 Aug 23.
The African cichlid, Pseudocrenilabrus multicolor victoriae is a eurytopic fish that exhibits high levels of developmental plasticity in response to dissolved oxygen availability. In this study, F1 offspring from three sites in the Mpanga River drainage of Western Uganda characterized by different dissolved oxygen (D.O.) regimes were reared under normoxic or hypoxic conditions. After 1 year, enzymes were measured to determine the tissue metabolic capacity of four different tissues: muscle, heart, brain and liver. The enzymes measured were pyruvate kinase [PK], lactate dehydrogenase [LDH], citrate synthase [CS], and cytochrome C oxidase [CCO], and an additional two, malate dehydrogenase (MDH) and fructose 1,6-bisphosphatase (FBPase), were examined in the liver only. Individuals reared under hypoxia exhibited elevated levels of LDH and CCO in the heart; and depressed activity levels of brain CS and liver CCO and MDH relative to normoxia-reared sibs. Results from this study demonstrate that long-term exposure to hypoxia during development can induce changes in the metabolic capacities of P. multicolor. This flexibility may be important in facilitating persistence in variable and/or novel environments, and in the face of increasing global hypoxia.
维多利亚非洲慈鲷，又名五彩博氏鲷，是一种广适性鱼类，对溶解氧含量的变化表现出高度的发育可塑性。在这项研究中，来自乌干达西部姆潘加河不同溶解氧（D.O.）区域的 F1 后代在常氧或低氧条件下进行培育。1 年后，测量酶以确定四种不同组织（肌肉、心脏、大脑和肝脏）的组织代谢能力。测量的酶有丙酮酸激酶 [PK]、乳酸脱氢酶 [LDH]、柠檬酸合酶 [CS] 和细胞色素 C 氧化酶 [CCO]，仅在肝脏中还检查了另外两种酶，苹果酸脱氢酶 (MDH) 和果糖 1,6-二磷酸酶 (FBPase)。在低氧环境中饲养的个体，心脏中的 LDH 和 CCO 水平升高；而大脑 CS 和肝脏 CCO 和 MDH 的活性水平相对于常氧饲养的同胞则降低。这项研究的结果表明，发育过程中长期暴露于低氧环境会引起 P. multicolor 代谢能力的变化。这种灵活性对于在变化和/或新环境中维持生存，以及应对全球缺氧的增加可能非常重要。
