CAJ | 학술논문

在目前集约化水产养殖模式下，草鱼肝脂质代谢紊乱问题比较严重，已引起人们的高度关注。为获知糖对草鱼肝脂代谢的影响及作用机理，本研究分别从活体和细胞水平上分析了糖对肝脂代谢5个关键基因转录水平变化的影响。采用实时荧光定量 PCR（qRT‐PCR）技术，检测了在低糖（糖含量24％）和高糖（糖含量42％）投喂条件下草鱼肝脏中固醇调节元件结合蛋白‐1c、过氧化物酶体增殖物激活受体α和乙酰辅酶A羧化酶的转录水平变化，H·E染色观察肝脏组织形态学变化；并检测了在不同浓度葡萄糖作用下，草鱼肝细胞中固醇调节元件结合蛋白‐1c、脂肪酸合酶和脂蛋白脂酶基因的表达变化。结果显示，肝组织中固醇调节元件结合蛋白‐1c、乙酰辅酶A羧化酶在高糖组中的表达量显著高于对照组和低糖组（P ＜0．05），过氧化物酶体增殖物激活受体α在高糖和低糖条件下变化不明显（P＞0．05）；H · E染色观察发现在高糖条件下草鱼肝组织出现了大量的脂肪蓄积；在其肝细胞中固醇调节元件结合蛋白‐1c、脂肪酸合酶、脂蛋白脂酶的mRNA表达量随葡萄糖浓度增加均呈先升后降趋势，分别在葡萄糖浓度为10 mmol／L和20 mmol／L时达到最高值（P ＜0．05）。研究结果表明，葡萄糖可能通过调节固醇调节元件结合蛋白‐1c、乙酰辅酶A羧化酶和脂蛋白脂酶等基因的表达进而调节体内糖向脂的转化过程。研究结果为丰富鱼类糖代谢调控机理提供研究资料，并有望为提高鱼类饲料糖的利用效率提供理论依据。
재목전집약화수산양식모식하，초어간지질대사문란문제비교엄중，이인기인문적고도관주。위획지당대초어간지대사적영향급작용궤리，본연구분별종활체화세포수평상분석료당대간지대사5개관건기인전록수평변화적영향。채용실시형광정량 PCR（qRT‐PCR）기술，검측료재저당（당함량24％）화고당（당함량42％）투위조건하초어간장중고순조절원건결합단백‐1c、과양화물매체증식물격활수체α화을선보매A최화매적전록수평변화，H·E염색관찰간장조직형태학변화；병검측료재불동농도포도당작용하，초어간세포중고순조절원건결합단백‐1c、지방산합매화지단백지매기인적표체변화。결과현시，간조직중고순조절원건결합단백‐1c、을선보매A최화매재고당조중적표체량현저고우대조조화저당조（P ＜0．05），과양화물매체증식물격활수체α재고당화저당조건하변화불명현（P＞0．05）；H · E염색관찰발현재고당조건하초어간조직출현료대량적지방축적；재기간세포중고순조절원건결합단백‐1c、지방산합매、지단백지매적mRNA표체량수포도당농도증가균정선승후강추세，분별재포도당농도위10 mmol／L화20 mmol／L시체도최고치（P ＜0．05）。연구결과표명，포도당가능통과조절고순조절원건결합단백‐1c、을선보매A최화매화지단백지매등기인적표체진이조절체내당향지적전화과정。연구결과위봉부어류당대사조공궤리제공연구자료，병유망위제고어류사료당적이용효솔제공이론의거。
In current intensive aquaculture ,the hepatopancreatic lipid metabolic disorderis are serious in grass carp (Ctenopharyngodon idellus) ,and has caused the attention of people .The transcriptional effects of carbohydrates on the five key genes involved in lipid metabolism in hepatopancreas of grass carp were in‐vestigated in vivo and in vitro in order to get the exact regulatory mechanisms of carbohydrates on lipid me‐tabolism in grass carp .The expression levels of sterol regulatory element‐binding protein‐1c (SREBP‐1c) , peroxisome proliferator‐activated receptorα(PPARα) and acetyl‐CoA carboxylase (ACC) were analyzed in hepatopancreas of grass carp fed the diets containing low‐carbohydrates (24% ) and high carbohydrates (42% ) using quantitative real‐time fluorescent PCR technology .T he histological observation w as conduc‐ted in hepatopancreas of grass carp fed the diets containing low and high carbohydrates by H‐E staining . The SREBP‐1c ,fatty acid synthase (FAS) and lipoprotein lipase (LPL) gene expression patterns in vitro hepatocytes treated with different concentrations of glucose were detected by the quantitative real‐time flu‐orescent PCR .The results showed that there were significant higher relative expression levels of SREBP‐1c and ACC in the high carbohydrate group than in the control and in low carbohydrate group (P<0 .05) , without significantly differences in relative expression level of PPARα between the high carbohydrate group and the low carbohydrate group (P > 0 .05) .The histological observation revealed that fat accumu‐lation was induced in the hepatopancreas ,and the expression level of SREBP‐1c ,FAS and LPL was in‐creased first and then decreased with the increasing concentrations of glucose in the hepatocyte cultures , with the maximal level of SREBP‐1c at 10 mmol/L ,and the maximal FAS and LPL at 20 mmol/L in grass carp fed the high carbohydrate diet ( P< 0 .05 ) . T he findings suggested that the expression levels of SREBP‐1c ,FAS ,and LPL were adjusted by dietary glucose ,which may further regulate the transforma‐tion of carbohydrate into fat .T he research data can enrich the glucose metabolism regulation mechanism in fish ,and is expected to provide a theoretical basis for improvement of utilization efficiency of carbohydrates in fish feed .