为探讨盐度胁迫对尼罗罗非鱼（）肝脂肪酸代谢的影响，本研究分别在盐度8和盐度16的水体中对尼罗罗非鱼进行两周的胁迫实验，比较盐度胁迫过程中肝脂肪酸组成变化，以及脂蛋白脂肪酶（lipoprotein lipase，LPL）、苹果酸酶（malic enzyme，ME）和过氧化物酶体增殖物激活受体α亚基（peroxisome proliferator-activated receptor，PPAR-α） mRNA表达量变化。结果表明，胁迫12 h，盐度组血浆渗透压升至最高，16盐度组血浆渗透压显著高于8盐度组（<0.05），96 h后饱和脂肪酸含量逐渐恢复至初始水平；胁迫期间，盐度组单不饱和脂肪酸含量显著低于淡水组（<0.05）。盐度组脂蛋白脂肪酶（LPL）、苹果酸酶（ME）、过氧化物酶体增殖物激活受体α亚基（PPAR-α） mRNA表达量均显著高于淡水组（<0.05）。结果表明，盐度胁迫影响了肝脂肪酸组成和脂代谢过程。本研究旨在为鱼类渗透调节中脂类能量利用提供基础资料。

Salinity is one of the most important factors that influence the physiological status of fish. To adapt to different salinity environments, fish need to consume a lot of energy to maintain osmotic pressure balance. As an intermediate product of lipid metabolism, fatty acids not only play an important role in physiological and biochemical processes, but are also an important energy source for the body. The liver is the main lipid storage organ and the main organ for fatty acid metabolism in fish. is a unique model species to study salinity adaptation because it can live in a wide range of salinities. To investigate the effects of salinity on the metabolism of fatty acids in the liver of , this study compared the changes in fatty acid composition and the mRNA expressions of lipoprotein lipase (LPL), malic enzyme (ME) and peroxisome proliferator-activated receptor-alpha (PPAR-α) in the liver of Nile tilapia in saline water (levels 8 and 16) during a two week salinity stress period. The results showed that the plasma osmolality in the salinity group rose to the highest level in 12 h, and the plasma osmolality in the 16-salinity group was significantly higher than in the 8-salinity group. Meanwhile, the plasma osmolality gradually decreased and tended to be stable in the latter stage of treatments. Before 96 h, the content of saturated fatty acids in the liver of the salinity groups was significantly lower than the freshwater group (<0.05). After 96 h, they gradually recovered to the initial level. The content of monounsaturated fatty acids in the liver of the salinity group was significantly lower than the freshwater group (<0.05). The content of long-chain polyunsaturated fatty acids (mainly docosahexaenoic acid DHA, Eicosapentaenoic Acid EPA, and Arachidonic Acid ARA) in the liver of the salinity groups was significantly higher than the freshwater group (<0.05). The mRNA expressions of LPL, ME, and PPAR-α in the liver of the salinity groups was significantly higher than the freshwater group (<0.05). These results indicate that the composition of fatty acids in the liver and lipid metabolism can be impacted by salinity stress, which provides basic information on lipid energy utilization in fish osmoregulation.

S965

国家现代农业产业技术体系专项（CARS-46）.