不同n-3/n-6多不饱和脂肪酸构成比对大鼠脂代谢和食欲的影响

目的研究不同n-3/n-6配比脂肪酸对大鼠食欲影响及其与腺苷酸活化蛋白激酶(AMPK)基因表达的关系。方法58只SD大鼠适应性喂养7天后,尾静脉取血。根据血清总胆固醇(TC)水平随机分为6组:空白组(基础饲料),高脂组(高脂饲料),高脂1∶1组(高脂饲料+n-3/n-6=1∶1油),高脂1∶5组(高脂饲料+n-3/n-6=1∶5油),低脂1∶1组(脱脂基础饲料+n-3/n-6=1∶1油),低脂1∶5组(脱脂基础饲料+n-3/n-6=1∶5油),喂养45天,观察大鼠摄食与体重增长,并于实验第0、15、30和45天测定血清总胆固醇(TC)和甘油三酯(TG)含量。于45天处死动物,取下丘脑,用RT-PCR分别测下丘脑组织中NPY、AMPK-α2 mRNA表达。结果添加PUFA的四个组血清TC、TG、摄食量、体重及NPY、AMPK-α2mRNA表达均比高脂组大鼠明显降低(P<0.05)。结论PUFA改善血脂可能是通过影响AMPK表达,从而抑制下丘脑食欲相关基因表达,进而影响血脂代谢。     

不同n-6/n-3多不饱和脂肪酸构成比对高脂饲料喂养大鼠脂联素和糖脂代谢及抗氧化能力的影响

目的探讨高脂饲料喂养条件下,不同n-6/n-3多不饱和脂肪酸(polyunsaturated fatty acid,PUFA)构成比对大鼠脂联素和糖脂代谢及抗氧化能力的影响。方法50只雄性Wistar大鼠按体重随机分为5组:1个普通饲料组(脂肪供能比17%,n-6/n-3PUFA=5∶1)和4个高脂饲料组(脂肪供能比均为42%,n-6/n-3 PUFA构成比分别为1∶1、5∶1、10∶1、20∶1)。喂养12周后检测大鼠血糖和血脂(0、4、8和12周)、血清抗氧化指标(0和12周)以及睾周脂肪组织脂联素mRNA、蛋白表达和血清脂联素水平(12周)。结果大鼠各指标初始值组间差异均无统计学意义(P>0.05)。12周时,n-6/n-3PUFA 10∶1、20∶1组血糖显著高于对照组(P<0.05),4个高脂组血清总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)显著高于对照组(P<0.01),其中20∶1组TG显著高于其余3组(P<0.01);4个高脂组谷胱甘肽过氧化物酶和超氧化物歧化酶含量显著低于对照组(P<0.05),其中20∶1组下降最明显,丙二醛含量显著高于对照组(P<0.05),其中10∶1组上升最明显;20∶1组脂联素mRNA表达显著低于对照组、1∶1组和5∶1组(P<0.05),5∶1组脂联素蛋白表达水平显著高于其余高脂组(P<0.05),而20∶1组表达水平最低(P<0.05)。结论较低的n-6/n-3 PUFA构成比(1∶1和5∶1),有助于改善高脂饲料条件下大鼠糖脂代谢及抗氧化能力,提高脂联素表达。     

不同n-6/n-3 PUFA构成比对大鼠脂联素表达的影响及与CDK5/PPARγ关系

目的研究在膳食脂肪产热比26.52%时,不同n-6/n-3多不饱和脂肪酸(polyunsaturated fatty acids,PUFA构成比对大鼠脂联素表达的影响及CDK5/PPARγ介导的机制。方法 50只雄性Wistar大鼠按体质量(body weight, bw)随机分成对照组及4个实验组。对照组喂基础饲料,实验组分别将饲料中n-6/n-3PUFA构成比调配为1:1、5:1、10:1和20:1,测定干预前血清脂联素含量。膳食干预12w,记录体质量变化,计算食物利用率及能量转化效率,测定睾周、肾周脂肪组织重量、肾周脂肪组织脂联素表达、血清脂联素含量、肾周脂肪组织PPARγ、CDK5及p-PPARγ(Ser273)的表达。结果当n-6/n-3 PUFA构成比高于5:1,大鼠能量转化效率升高、体质量增加并伴有肾周脂肪蓄积。n-6/n-3 PUFA构成比为1:1、5:1膳食大鼠血清脂联素含量和PPARγ表达增加,CDK5、p-PPARγ蛋白降低;构成比为20:1膳食降低大鼠脂肪组织脂联素、PPARγ和CDK5蛋白的表达,且不能改变p-PPARγ蛋白表达。结论在正常的膳食脂肪供给情况下...     

n-3多不饱和脂肪酸抑制SphK1信号通路改善脓毒症的炎性反应

目的:观察富含n-3多不饱和脂肪酸(n-3 PUFA)的肠外营养(PN)能否通过鞘氨醇激酶1(SphK1)和磷酸鞘氨醇受体(S1P)途径影响机体的炎性反应. 方法:对大鼠实施颈外静脉置管,2d后行盲肠结扎穿孔,然后随机分为等渗盐水组(静脉输注等渗盐水,n=20)、鱼油组(鱼油+PN,n=20)和大豆油组(PN,n=20),随后行PN支持5d.另设正常对照组(n=10)实施假手术.检测血清IL-10和高迁移率族蛋白(HMGB-1)浓度、脾组织中SphK1、S1PR1、S1PR3表达情况以及SphK1酶活性. 结果:与对照组比,等渗盐水组大鼠SphK1 mRNA、蛋白表达和酶活性明显升高,S1PR3 mRNA和蛋白表达也上调;鱼油组血清IL-10和HMGB-1浓度显著降低;SphK1 mRNA、蛋白表达和酶活性显著受抑制;S1PR3 mRNA和蛋白表达也受抑. 结论:n-3 PUFA的PN可通过抑制SphK1和S1PR3通路改善脓毒症大鼠的炎性反应.     

不同n-6/n-3脂肪酸构成对小鼠心血管疾病危险因素的影响

目的研究不同脂肪酸构成对小鼠血脂代谢、炎症和氧化应激及内皮细胞功能的影响。方法雄性KM小鼠随机分为5组,分别喂饲正常对照饲料、猪油高脂饲料和n-6/n-3多不饱和脂肪酸(PUFA)比值为1∶1、5∶1、20∶1的高脂饲料5周,比较各组小鼠血清中甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、白介素-6(IL-6)、丙二醛(MDA)、超敏C反应蛋白(hsCRP)、肿瘤坏死因子(TNF-α)、脂质过氧化物(LPO)、8-异前列腺素F2α(8-isoPGF2α)、氧化型低密度脂蛋白(ox-LDL)、游离脂肪酸(FFA)、选择素(ES)和血管性血友病因子(v WF)的含量变化。结果猪油组LDL-C和非高密度脂蛋白胆固醇(non-HDL-C)水平显著高于其他各组(P0.05)。n-6/n-3 PUFA 1∶1组和5∶1组血清TG、TC水平显著低于猪油组(P0.05)。20∶1组血清FFA水平显著高于1∶1组和5∶1组(P0.05)。1∶1组和5∶1组血清炎症因子和氧化应激指标及ES水平均显著低于猪油组和20∶1组(P0.05)。5∶1组血清v WF水平显著低于猪油组和20∶1组(P0.05)。结论与猪油和高n-6/n-3 PUFA比值高脂饲料相比较,低n-6/n-3PUFA比值高脂饲料可改善小鼠脂代谢、炎症与氧化应激和内皮细胞功能。     

n-6/n-3 PUFA对乳腺癌大鼠ER及p53表达影响

目的 探讨不同比例的n-6/n-3多不饱和脂肪酸(PUFA)对N-甲基亚硝基脲(MNU)诱导的乳腺癌大鼠乳腺组织中雌激素受体(ER)和p53表达的影响。方法 雌性SD大鼠随机分为n-6 PUFA、10:1 n-6/n-3、5:1n-6/n-3、1:1 n-6/n-3和正常对照5组,前4组以50mg/(kg·bw)MNU单次腹腔注射诱导乳腺肿瘤发生,正常对照组注射等体积无菌生理盐水。给药后立即分组喂养不同饲料,在8和18周时处死动物,RT-PCR和蛋白印迹(Western blot)技术检测各组大鼠乳腺组织ER和p53表达。结果 4组乳腺癌大鼠乳腺组织中ER和p53的表达均较正常对照组((0.73±0.11),(0.08±0.01))有所升高,其中n-6组最高((1.32±0.18),(1.43±0.56)),其余各组随n-6/n-3比值减小而下降,1:1 n-6/n-3组((0.95±0.12),(0.12±0.06))显著低于n-6组(P<0.05)。结论 不同比例n-6/n-3多不饱和脂肪酸对MNU诱导的乳腺癌大鼠乳腺组织ER和p53的表达具有不同影响,1:1 n-6/n-3膳食脂肪酸构成能有效抑制乳腺癌大鼠乳腺组织ER和p53表达的升高。     

多不饱和脂肪酸不同配比对大鼠血脂影响

目的 研究不同n-3/n-6配比的多不饱和脂肪酸(PUFA)对大鼠血脂影响。方法 将58只SD大鼠根据血清总胆固醇(TC)水平随机分为6组,分别给予基础饲料、高脂饲料和添加n-3/n-6不同配比PUFA的高脂或基础饲料。于第15,30,45 d分别测血脂水平,第45 d取脂肪组织称重并测肝组织中过氧化物酶体增殖物激活受体γ(PPAR-γ)和腺苷酸活化蛋白激酶α2(AMPK-α2)的mRNA表达。结果 摄入添加PUFA膳食的4组大鼠45d后血清甘油三酯(TG)分别为(1.15±0.37),(1.25±0.56),(1.00±0.25),(1.17±0.30)mmol/L,均明显低于高脂组的(1.73±0.33)mmol/L;TC分别为(1.80±0.18),(1.89±0.20),(1.41±0.21),(1.58±0.16)mmol/L,均明显低于高脂组的(2.23±0.19)mmol/L;低密度脂蛋白胆固醇(LDL-C)分别为(1.00±0.23),(1.25±0.18),(1.06±0.13),(1.25±0.14)mmol/L,均明显低于高脂组的(1.53±0.27)mmol/L;其脂体比、PPAR-γmRNA、AMPK-α2mRNA表达量均明显高于高脂组,差异均有统计学意义(P<0.05)。结论 PUFA改善大鼠高血脂并降低脂肪积累,可能与肝组织AMPK和PPAR-γ等脂肪酸氧化基因表达增加有关。     

n-6/n-3脂肪酸配方油对大鼠血脂和脂质过氧化的影响

目的研究不同脂肪酸n-6/n-3组成的配方油对大鼠血脂和脂质过氧化的影响.方法成年SD雄性大鼠喂饲含相同胆固醇(0.5%,W/W)、饱和脂肪酸(占供给能量10%)、单不饱和脂肪酸(占供给能量13%)和多不饱和脂肪酸(占供给能量12%),但不同脂肪酸n-6/n-3比(6.48、2.07、0.93、031)的4种配方油的高脂合成饲料60天,观察大鼠血脂及脂质过氧化的变化.结果4种配方油比猪油均显著降低血清总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、LDL-C/HDL-C、AI[(TC-HDL-C/HDL-C,致动脉粥样硬化指数)],升高HDL-C/TC;配方油D具有独特的升高血清HDL-C2的作用;配方油A、C、D显著降低血清TG,而配方油B作用不明显.以n-3多不饱和脂肪酸占优势的配方油C、D比以n-6多不饱和脂肪酸占优势的配方油A、B显著地升高血清丙二醛,降低血清超氧化物歧化酶、全血谷胱甘肽过氧化物酶活性.4组配方油大鼠的心、脑脂褐质含量均比实验前增高,各配方油间无显著差异;心、脑脂褐质与血脂的相关分析发现心、脑脂褐质与血清TC、LDL-C呈正相关,与血清高密度脂蛋白胆固醇(HDL-C)、甘油三酯(TG)关系不明显.结论从预防动脉粥样硬化的角度,脂肪酸n-6/n-3比在2.07～6.48范围内是合理的脂肪酸供给模式.     

不同配比高n-3/n-6多不饱和脂肪酸对大鼠胰岛素抵抗的影响

目的探讨长期摄入高脂不同n-3/n-6多不饱和脂肪酸(PUFAs)构成比的饮食后,大鼠胰岛素敏感性及血清炎症因子表达水平的变化。方法 40只刚断乳雄性SD大鼠适应性喂养7天后,根据体重随机分为4组:空白对照组(基础饲料)、高脂组(猪油)、高脂1∶1组(n-3/n-6为1∶1)和高脂1∶4组(n-3/n-6为1∶4),每组10只。每周记录一次大鼠体重,喂养16周处死动物,检测大鼠血脂、血清胰岛素敏感性和血清炎症因子(IL-6、TNF-α和hs-CRP)表达水平。结果与空白对照组相比,其他3个组体重显著上升(P<0.05);高脂1∶1组胰岛素敏感性与空白对照组比较,差异无显著性,且显著高于高脂组和高脂1∶4组(P<0.05);与高脂组相比,高脂1∶1组血清TNF-α和hs-CRP表达水平显著下降(P<0.05)。结论长期摄取高多不饱和脂肪酸同样具有肥胖风险,提高n-3PUFAs在膳食构成中的比重可以有效抑制炎症因子表达,改善胰岛素敏感性,预防胰岛素抵抗的发生。     

n-6/n-3多不饱和脂肪酸对3T3-L1脂肪细胞脂联素及PPARγ表达的调节作用

目的探讨不同比例、不同浓度的n-6/n-3多不饱和脂肪酸(PUFA)对3T3-L1脂肪细胞脂联素及过氧化物酶体增殖物激活受体(PPARγ)表达的调节作用。方法用不同比例、不同浓度的n-6/n-3PUFA分别处理已诱导分化成熟的3T3-L1脂肪细胞,用实时定量PCR和Western-Blot法测定各处理组胞内脂联素、PPARγmRNA表达水平以及脂联素蛋白表达水平。结果与空白对照相比,n-6/n-3PUFA为1:1时,在25~200μmol/L范围内时显著促进脂联素mRNA表达;比例为5:1时25、50μmol/L浓度组及比例为10:1时50μmol/L浓度组均显著促进脂联素mRNA表达。比例为20:1及30:1时,各浓度组对脂联素mRNA表达主要起抑制作用。在脂肪酸浓度达到400μmol/L时,n-6/n-3PUFA无论何种构成比均抑制脂联素表达。胞内脂联素蛋白表达与脂联素mRNA表达基本一致。PPARγ表达与脂联素表达呈正相关。结论 n-6/n-3PUFA可能通过PPARγ途径,以剂量依赖方式调节脂联素表达。     

广州成人膳食n-6/n-3脂肪酸比值与心血管疾病危险因素的关系

目的分析广州40～65岁居民膳食n-6/n-3脂肪酸比值与心血管疾病危险因素的关系。方法 40～65岁广州市民1133人,采用定量食物频数问卷调查对象的每日摄入食物种类和数量,计算能量和营养素摄入量,检测其红细胞膜脂肪酸构成、血脂及颈动脉内中膜厚度(IMT),分析n-6/n-3比值大小高Q3,中Q2,低Q1与血压、血脂和IMT的关系。结果 995人资料完整纳入分析。对象日均膳食总能量摄入为9.10±2.09MJ、脂肪供能比为(34.3±7.9)%。膳食n-6/n-3脂肪酸比值为(29.74±22.71):1,红细胞膜n-6/n-3脂肪酸比值为(2.7±1.0):1,膳食SFA:MUFA:PUFA为1:1.5:1。膳食n-3脂肪酸摄入量与红细胞膜n-3构成比、膳食n-6/n-3比值与红细胞膜n-6/n-3比值均呈显著正相关关系。膳食n-6/n-3比值最高组Q3(>31.16)对象的收缩压、TC和IMT水平显著高于最低组Q1(<17.40);红细胞膜n-6/n-3比值最高组Q3(>3.04)和中间组Q2(2.18～3.03)对象的收缩压、舒张压、TC、LDL-C及IMT水平均显著高于最低组Q1(≤2.17)。结论广州市40～65岁居民膳食n-6/n-3脂肪酸比值约为30:1;该比值小于17.40:1时,有较低的血压,总胆固醇及IMT水平。     

Lack of effect of dietary n-6:n-3 PUFA ratio on plasma lipids and markers of insulin responses in Indian Asians living in the UK

Summary Background Indian Asians living in Western Countries have an over 50 % increased risk of coronary heart disease (CHD) relative to their Caucasians counterparts. The atherogenic lipoprotein phenotype (ALP), which is more prevalent in this ethnic group, may in part explain the increased risk. A low dietary long chain n-3 fatty acid (LC n-3 PUFA) intake and a high dietary n-6 PUFA intake and n-6:n-3 PUFA ratio in Indian Asians have been proposed as contributors to the increased ALP incidence and CHD risk in this subgroup. Aim To examine the impact of dietary n-6:n-3 PUFA ratio on membrane fatty acid composition, blood lipid levels and markers of insulin sensitivity in Indian Asians living in the UK. Methods Twentynine males were assigned to either a moderate or high n-6:n-3 PUFA (9 or 16) diet for 6 weeks. Fasting blood samples were collected at baseline and 6 weeks for analysis of triglycerides, total-, LDL- and HDL-cholesterol, non-esterified fatty acids, glucose, insulin, markers of insulin sensitivity and C-reactive protein. Results Group mean saturated fatty acid, MUFA, n-6 PUFA and n-3 PUFA on the moderate and high n-6:n-3 PUFA diets were 26 g/d, 43 g/d, 15 g/d, 2 g/d and 25 g/d, 25 g/d, 28 g/d, 2 g/d respectively. A significantly lower total membrane n-3 PUFA and a trend towards lower EPA and DHA levels were observed following the high n-6:n-3 PUFA diet. However no significant effect of treatment on plasma lipids was evident. There was a trend towards a loss of insulin sensitivity on the high n-6:n- 3 PUFA diet, with the increase in fasting insulin (P = 0.04) and HOMA IR [(insulin x glucose)/ 22.5] (P = 0.02) reaching significance. Conclusion The results of the current study suggest that, within the context of a western diet, it is unlikely that dietary n-6:n-3 PUFA ratio has any major impact on the levels of LC n-3 PUFA in membrane phospholipids or have any major clinically relevant impact on insulin sensitivity and its associated dyslipidaemia. Source of support: This project was funded by the Food Standards Agency (FSA), UK.     

膳食n-6/n-3脂肪酸比值对小鼠淋巴细胞脂肪酸构成和功能的影响

目的观察膳食n6n3脂肪酸比值对淋巴细胞脂肪酸构成及细胞功能的影响。方法BALBc小鼠随机分为5组n6n3比值分别为1(A组)、75(B组)、15(C组)、30(D组)和正常对照组,其中实验组S∶M∶P模拟中国居民膳食脂肪酸摄入的S∶M∶P为1∶15∶1,正常对照组为AIN93G配方的1∶15∶37。基础饲料采用AIN93G配方,脂肪酸构成以食用油脂调配。饲养12周。测定小鼠T淋巴细胞功能,脾淋巴细胞脂肪酸构成、PGE2水平。结果n6n3比值接近1时,小鼠T淋巴细胞增殖活性、CD4+、CD8+T细胞比例、培养上清IL2、PGE2水平显著降低;淋巴细胞C18∶2、C20∶4、n6PUFA含量显著减少;C22∶6、C16∶1、C18∶1、总MUFA含量明显高于其他实验组。淋巴细胞C22∶6含量与淋巴细胞增殖活性显著负相关;C20∶5含量与CD4+T淋巴细胞比例、IL2水平显著负相关;C16∶1含量与CD4+、CD8+T淋巴细胞比例显著负相关。结论小鼠脾淋巴细胞的脂肪酸构成受膳食脂肪酸构成的影响;n6n3比值为1组与比值为30的膳食组相比较,小鼠T淋巴细胞增殖活性受到抑制。     

Dietary n-3 and n-6 fatty acids alter avian metabolism: metabolism and abdominal fat deposition

The effects of dietary saturated fatty acids and polyunsaturated fatty acids (PUFA) of the n-3 and n-6 series on weight gain, body composition and substrate oxidation were investigated in broiler chickens. At 3 weeks of age three groups of chickens (n 30; ten birds per group) were fed the fat-enriched experimental diets for 5 weeks. These diets were isonitrogenous, isoenergetic and contained 208 g protein/kg and 80 g edible tallow, fish oil or sunflower oil/kg; the dietary fatty acid profiles were thus dominated by saturated fatty acids, n-3 PUFA or n-6 PUFA respectively. Resting RQ was measured in five birds from each treatment group during weeks 4 and 5 of the experiment. There were no significant differences between treatments in total feed intake or final body mass. Birds fed the PUFA diets had lower RQ and significantly reduced abdominal fat pad weights (P<0.01) compared with those fed tallow. The dietary lipid profile changes resulted in significantly greater partitioning of energy into lean tissue than into fat tissue (calculated as breast lean tissue weight:abdominal fat mass) in the PUFA groups compared with the saturated fat group (P<0.01; with no difference between the n-3 and n-6 PUFA groups). In addition, the PUFA-rich diets lowered plasma concentrations of serum triacylglycerols and cholesterol. The findings indicate that dietary fatty acid profile influences nutrient partitioning in broiler chickens.     

Total fat and (n-3):(n-6) fat ratios influence eicosanoid production in mice.

Previous studies have not addressed the effect of differing fat intake on the effectiveness of varying (n-3) polyunsaturated fatty acid (PUFA) ingestion in altering tissue composition and eicosanoid production. This study examined (n-3):(n-6) PUFA ratios of 0, 0.1:1, 0.2:1, 0.4:1, and 1:1 with total fat at 5, 10, 15, and 20 g/100 g of diet and (n-6) PUFA fixed at 1.5 g/100 g of diet on tissue composition and peritoneal cell eicosanoid response to an in vivo inflammatory stimulus in 240 mice. Both (n-3) PUFA and total fat intake influenced tissue composition and eicosanoid biosynthesis. Increased (n-3) PUFA intake was associated with an increase in tissue (n-3) PUFA and a decrease in long-chain (n-6) PUFA. Although hepatic tissue linoleic acid (LA) was not altered by (n-3) PUFA intake or changes in total fat, peritoneal cell LA increased in response to increasing total fat but was unaffected by changes in dietary (n-3) PUFA. Four-series leukotrienes (LT) decreased progressively with increased (n-3) PUFA at all fat intake levels. In addition, four-series LT decreased with increased total fat at low (n-3):(n-6) ratios (0 and 0.1). At high (n-3):(n-6) ratios (0.4 and 1.0) increasing dietary fat between the 5 and 15 g/100 g diets increased four-series LT synthesis, which reached a plateau between 15 and 20 g fat/100 g diets. Five-series LT production generally rose with increased (n-3) PUFA intake; this effect was most evident in mice fed the 5 g fat/100 g diet. Increasing total dietary fat at the three highest (n-3):(n-6) ratios (0.2, 0.4, 1.0) decreased five-series LT production. Elevated (n-3) PUFA and total fat intake exerted an additive effect with respect to prostacyclin (PGI(2)) production because it was reduced with increasing intakes of both. Compared with the mice consuming the no (n-3) 5 g/100 g diets, PGI(2) levels were reduced by 88% in mice consuming the highest total fat and (n-3) PUFA diets. At low fat intake (5 and 10 g/100 g diet), increasing the (n-3) PUFA intake was associated with a decrease in PGE(2) synthesis. However, unlike PGI(2), high fat intake reduced PGE(2) to basal levels with no further reduction induced by increased (n-3) PUFA intake.     

孕期及哺乳期n-6/n-3脂肪酸变化对仔鼠脑源性神经营养因子基因表达的影响

目的 探讨孕期及哺乳期n-3 多不饱和脂肪酸(n-3 polyunsaturated fatty acids,n-3 PUFAs)摄入量及其与n-6 PUFAs比例对仔鼠脑源性神经营养因子(brain-derived neurotrophic factor,bdnf)基因表达的影响。方法 使用6~8周龄清洁级C57BL/6J雌性小鼠,随机分为5 组,分别给予n-3 PUFAs缺乏和4种不同含量n-3 PUFAs(n-6/n-3 PUFAs比值分别为15∶1、5∶1、1∶1及1∶5)饲料喂养。小鼠12~14周龄时雌雄合笼交配繁殖,仔鼠断乳后继续行母鼠相同饲料喂养,分别在生后7 d、21 d和3 月时被处死后取脑。同时,分别从n-3 PUFAs缺乏组和n-6/n-3 PUFAs(5∶1)组中选取等量仔鼠,21 d断乳后相互交换饲料喂养至3个月,处死后取脑。采用实时荧光定量PCR技术测定脑皮质bdnf基因mRNA的表达。结果 与n-3 PUFAs缺乏饲料组相比,对于7 d和21 d幼年仔鼠,只有n-6/n-3 PUFAs(1∶5)饲料组bdnf基因mRNA表达量显著升高;对于3 月龄成年仔鼠,各含n-3 PUFAs饲料组bdnf基因mRNA的表达均升高。对于孕期和哺乳期n-3 PUFAs缺乏饲料组仔鼠,断乳后给予含n-3 PUFAs饲料喂养未能提升脑皮质bdnf基因mRNA表达;而孕期和哺乳期含n-3 PUFAs饲料喂养的仔鼠,断乳后给予n-3 PUFAs缺乏饲料喂养时,脑皮质bdnf基因mRNA表达量见一定程度的升高。结论 孕期及哺乳期可能需要较高的n-3 PUFAs摄入,才能满足幼年期诱导脑bdnf表达之需。保证生命早期n-3 PUFAs的适量摄入,有助于维持成年期bdnf的正常表达。