多沙唑嗪光学异构体对高血脂家兔血脂水平的影响

目的:观察左旋多沙唑嗪(-)DOX、右旋多沙唑嗪(+)DOX和消旋多沙唑嗪(±)DOX对高血脂家兔血脂水平及动物死亡率的影响。方法:取普通级雄性新西兰大耳白兔,给予高脂饮食4周后,血清TC小于10mmol/L的8只家兔为普通饮食组,饲以标准饲料。血清TC大于10mmol/L的40只家兔随机分为4组(n=10):高脂模型组、高脂模型+(-)DOX组、高脂模型+(+)DOX组以及高脂模型+(±)DOX组。普通饮食组和高脂模型组家兔腹腔注射无菌双蒸水;其他3组家兔分别腹腔注射(-)DOX、(+)DOX和(±)DOX,连续9周。分析药物对兔血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)的影响。结果:饲以高脂饮食13周时模型组家兔死亡率达40%,远远高于普通饮食组家兔(10%),亦明显高于(±)DOX和(-)DOX处理组。模型组家兔随高脂饲养的时间延长,血清LDL-C水平进一步显著升高(P0.05和P0.01);而各药物处理组动物的血清LDL-C水平未显著升高(P0.05)。结论:(-)DOX和(±)DOX可提高高脂饮食家兔的生存率,并对高血脂家兔的血清LDL-C紊乱具有轻度的改善作用;该作用可能不是其提高高脂饮食家兔生存率的主要作用机制。     

山楂籽油降血脂作用研究

采用不同剂量山楂籽油对小鼠进行灌胃试验,研究其对血脂水平的影响。结果表明山楂籽油组小鼠的血清甘油三酯(TG),总胆固醇(TC),低密度脂蛋白胆固醇(LDL-C)和动脉硬化指数(AI)均不同程度(P<0.05或P<0.01)低于高脂模型组,而高密度脂蛋白胆固醇(HDL-C)却明显(P<0.01)高于高脂模型组,说明山楂籽油确具显著(P<0.05)降低小鼠血脂作用。     

16S rDNA测序研究高脂饮食诱导的高脂血症大鼠肠道菌群变化

目的 通过高脂饮食诱导大鼠高脂血症,采用16S rDNA测序检测高脂血症大鼠肠道菌群变化情况.方法 SD大鼠20只(清洁级),按体质量随机分为模型组和对照组,对照组大鼠给予维持饲料,模型组大鼠给予高脂饲料.1周后检测血清总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)和高密度脂蛋白胆固醇(HDL-C...     

毛菊苣醇提物对高脂血症性脂肪肝大鼠作用机制初探

目的:目前,国内外研究集中在毛菊苣降糖降脂方面的作用,并已有相关药物上市,但实验表明毛菊苣在保肝降脂作用方面也具有很好的效果,本文旨在探讨毛菊苣醇提物治疗高脂血症性脂肪肝的作用机制。方法:采用高脂饮食喂饲大鼠复制高脂血症性脂肪肝大鼠模型,实验分组为模型组、毛菊苣醇提物治疗高剂量组和低剂量组、苯扎贝特对照组和正常对照组;以高、低剂量毛菊苣醇提物进行干预,然后测定各组大鼠血清及肝组织中乳酸脱氢酶(LDH)、低密度脂蛋白(LDL)、甘油三酯(TG)、胆固醇(TC)、丙二醛(MDA)等指标的含量。结果:模型组大鼠血清及肝组织中LDH、TG、TC、LDL、MDA等活性均较正常组明显升高(P0.05),说明高脂饲料造模成功;与模型组比较,测得各治疗组大鼠血清、肝组织中相应指标均明显降低(P0.05;或P0.1);毛菊苣醇提物高剂量组与阳性对照组相比无显著差异。结论:实验结果表明:通过高脂饮食饲喂SD大鼠建立高脂血症动物模型的实验是成功的;同时,毛菊苣醇提物能够使脂肪肝大鼠的体重降低,降低肝脏脂肪性病变,降低脂肪肝大鼠血清ALT、AST含量,降低大鼠血清TC、TG、LDL-c,升高HDL-c;对模型SD大鼠肝脏中异常升高的MDA、LDH、LD均有明显的降低作用;形态学检查显示,醇提物高剂组肝脏脂变程度明显减轻,脂滴数量减少,提示该药物具有保肝降脂的药理作用。     

蚕蛹油对大鼠非酒精性脂肪肝形成的影响

目的观察蚕蛹油对高脂大鼠模型的非酒精性脂肪肝形成的影响。方法SD大鼠100只,雌雄各半,按体重并参考血脂水平随机分为9组:空白对照组,高脂对照组,预防低剂量组,预防中剂量组,预防高剂量组,治疗低剂量组,治疗中剂量组,治疗高剂量组,及阳性对照组(月见草油),分别喂饲各种饲料。于第11周处死大鼠,检测肝脏的肝重指数和肝脏甘油三酯(triglyceride,TG)、总胆固醇(total cholesterol,TC)、丙二醛(malondialde-hyde,MDA)水平。结果实验11周末,预防组、治疗组和阳性对照组大鼠的肝重指数,肝脏TG、TC及MDA水平均明显低于高脂对照组(P<0.05),并具有剂量依赖性。结论蚕蛹油可通过调整脂质代谢,具有十分显著的预防和治疗非酒精性脂肪肝形成的效果,优于月见草油。     

三种金花茶提取物降脂作用实验研究

目的:探讨金花茶浓缩液、金花茶乙酸乙酯/二氯甲烷提取物以及金花茶水提物对高脂血症小鼠血脂的调节作用。方法:将小鼠按照体重随机分成正常饮食组和高脂饮食组,分别给予正常饲料和高脂饲料喂食,4周后将高脂饮食小鼠按照体重以及血脂水平(TC)随机分成金花茶浓缩液组、金花茶乙酸乙酯/二氯甲烷提取物组、金花茶水提物组以及辛伐他丁组。3种金花茶提取物以及辛伐他丁混悬液连续灌胃10周,同时给予高脂饮食。末次给药后禁食不禁水12 h,摘眼球取血,检测血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-C)、低密度脂蛋白(LDL-C)、谷丙转氨酶(ALT)、谷草转氨酶(AST)、超氧化物歧化酶(SOD)以及丙二醛(MDA)。结果:与模型组相比,金花茶浓缩液和辛伐他丁能显著降低血清TC、TG、LDL-C水平(P0.01或P0.05),但是对HDL-C无明显调节作用;对血清中的AST、ALT、SOD以及MDA影响不大。金花茶乙酸乙酯/二氯甲烷提取物以及水体物对血清中的TC、TG、LDL-C、HDL-C、AST、ALT、SOD及MDA无明显的调节作用。结论:金花茶浓缩液对高脂血症小鼠的血脂具有良好的调节作用。     

家兔低密度脂蛋白胆固醇增高及同步饮磁处理水时动脉内膜病理学变化的比较研究

目的:观察家兔实验性低密度脂蛋白胆固醇(LDL -c)增高及同步饮磁处理水时动脉内膜病理变化的区别,探讨磁处理水对动脉粥样硬化的预防作用。方法:新西兰雄性大白兔随机分为3组即对照组(NG)、模型组(ASG)和预防组(MWG) ,以高脂饲料复制家兔动脉粥样硬化(AS)模型。MWG家兔喂高脂饲料同步饮磁处理水,分阶段检测各组家兔血浆LDL -c含量并观察其主动脉内膜病理学改变。结果:MWG血浆LDL -c含量明显较ASG降低(P <0 .0 1,MWG主动脉内膜脂质沉积及粥样斑块形成面积较ASG减小(P <0 .0 1,内膜增生程度较ASG减轻(P <0 .0 1)。结论:提示磁处理水在家兔实验性高LDL -c血症及AS的预防中起一定作用。     

小檗碱对动脉粥样硬化形成的抑制作用及机制探讨

目的:研究小檗碱(Berberine)对家兔动脉粥样硬化形成的抑制,并探讨其可能的作用机制。方法:将32只雄性新西兰大白兔随机分为正常组、模型对照组、小檗碱组和阿托伐他汀组,每组各8只。正常组以普通饲料喂养,其余各组高脂喂养,小檗碱组和阿托伐他汀组分别灌胃给予小檗碱(100 mg/kg,1次/d)和阿托伐他汀(5 mg/kg,1次/d),饲养12周。利用全自动生化分析仪测定兔血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)水平,酶联免疫吸附法测定血清ox-LDL、MCP-1、MMP-9水平。观察斑块破裂和血栓形成情况,并进行苏木素-伊红(HE)染色,测量病变区域内膜与中膜的厚度。结果:小檗碱可显著降低高脂喂养家兔的血清TC、TG、LD-C水平,降低血清血清炎症因子ox-LDL、MCP-1、MMP-9水平(P0.01),与阿托伐他汀组相比无显著性差异。同时小檗碱组的内膜增生程度明显小于模型对照组,和阿托伐他汀组接近。结论:小檗碱可改善动脉粥样硬化病变的程度,抑制斑块的形成,同时降低血清中炎症因子标志物。     

蓝树莓叶总黄酮对大鼠非酒精脂肪肝形成的防治作用

目的研究不同浓度的蓝树莓叶总黄酮对大鼠非酒精性脂肪肝(NAFLD)形成的防治作用。方法将60只雌、雄各半的SD大鼠分成5组:正常组(N)喂以普通饲料;高脂饮食模型组(M)喂以改良的高胆固醇饲料,诱发形成脂肪肝模型;蓝树莓叶总黄酮低、中、高浓度实验组(HLF1、HLF2、HLF3)在喂高脂饲料的同时分别灌胃20 mg·kg-1、40 mg·kg-1、80 mg·kg-1体重蓝树莓叶总黄酮溶液各3 m L。实验180 d后取动物血清、肝脏,检测动物血清中总胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白(HDL-C)、低密度脂蛋白(LDL-C)、谷丙转氨酶(AST)、谷草转氨酶(ALT)的含量,制备大鼠肝脏组织石蜡切片观察其病理学变化。结果蓝树莓叶总黄酮实验组各组与模型组相比,其血清的TC、TG、LDL-C、AST、ALT等含量均显著下降(P0.01),而HDL-C含量则明显上升(P0.01),且与蓝树莓叶总黄酮的浓度呈明显的量效关系。石蜡切片也显示蓝树莓叶总黄酮实验组动物肝脏中的脂质积累和脂肪肝病理学变化明显轻于模型组。结论蓝树莓叶总黄酮可以降低大鼠脂肪变性程度,对高脂饮食引起的脂肪肝具有明显的防治作用。     

降胆固醇益生菌联合大豆卵磷脂辅助降血脂保健食品的功能评价

目的研究降胆固醇益生菌联合大豆卵磷脂的保健食品的辅助降血脂作用。方法雄性SD大鼠喂普通饲料7d后,根据血清总胆固醇(TC)水平随机分成5组,每组10只,分别为样品高、中、低3个剂量组,模型对照组和空白对照组。以灌胃方式(10mL/kg)给予受试物,除空白对照组外,各组均喂高脂饲料,连续喂养30d后,称重、取大鼠眼血测定各项血脂指标。结果样品的低、中、高剂量组均能使高胆固醇血症大鼠血清TC和低密度脂蛋白胆固醇(LDL-C)水平降低,与模型对照组比较差异有统计学意义(P0.05)。结论降胆固醇益生菌联合大豆卵磷脂的保健食品对大鼠具有辅助降血脂作用。     

Does a HDL injection reduce the development of serum hyperlipidemia and progression of fatty streaks in cholesterol fed rabbits?

The influences of homologous (rabbit) or heterologous (human) high density lipoprotein (HDL) on the development of serum hyperlipidemia and progression of fatty streaks were studied in cholesterol fed rabbits. Three groups of New Zealand rabbits were fed a 0.5% cholesterol rich diet for 8 weeks. Additionally into these animals the following solutions were injected intravenously two times per week: group 1 (control): saline; group 2: human HDL dissolved in saline; group 3: rabbit HDL dissolved in saline. The animals of group 2 had lower serum cholesterol levels during the dietary period than rabbits of group 1 (p < 0.05) but the surface of intima covered with fatty streaks was the same as in group 1. On the other hand, the serum cholesterol level in rabbits of group 3 was the same as in group 1 during the whole experimental period, but the surface of aorta covered with fatty streaks was significantly lower (p < 0.05) in group 3 than in group 1. The results of this study support the hypothesis of an antiatherogenic action of HDL, which seems to be independent of the influence of HDL on the serum lipids but depends on the source of HDL.     

低密度脂蛋白胆固醇升高在家兔动脉粥样硬化发生发展中的意义

目的观察低密度脂蛋白胆固醇(LDL-c)对家兔动脉粥样硬化(AS)形成的影响,探讨AS的发生机制。方法以高脂饲料复制家兔实验性AS模型,分阶段检测家兔血清胆固醇(TC)、甘油三脂(TG)、高密度脂蛋白胆固醇(HDL-c)和低密度脂蛋白胆固醇(LDL-c)含量;观察主动脉内膜病理学变化;分析主动脉内膜增生程度及AS斑块面积与血浆脂蛋白水平的相关性。结果高脂组家兔主动脉粥样硬化面积和内膜增生程度明显较对照组增加(P<0.01),血浆LDL-c水平明显较对照组升高(P<0.01);动脉内膜增生程度及AS斑块面积均与血浆LDL-c水平呈非常显著正相关(r=0.837,P<0.001)。结论提示血浆LDL-c水平升高,是致AS发生发展的重要原因。     

有氧运动联合破壁蛋白核小球藻对高脂膳食大鼠脂代谢某些指标的影响

目的：研究有氧运动联合破壁蛋白核小球藻对高脂膳食大鼠脂代谢某些指标的影响。方法：55只雄性Wistar大鼠经过适应性饲养4 d后进行3 d、20 min/d的无负重游泳训练,筛选淘汰5只不适应游泳训练的大鼠后,按体重以数字随机分组法分为5组：普通膳食+安静对照组（C组）、高脂膳食+安静对照组（H组）、高脂膳食+小球藻+安静对照组（HC组）、高脂膳食+有氧运动组（HM组）、高脂膳食+有氧运动+小球藻组（HMC）,每组10只。HM组和HMC组进行6周每周6次60 min/d的无负重游泳训练。C组大鼠以普通饲料常规喂养;其余各组以高脂饲料喂养;HC组和HMC组大鼠灌胃破壁小球藻1次,灌胃剂量为3.9 g/（kg·d）,灌胃体积为5 ml/kg,其余各组ig等量生理盐水。6周后,测定大鼠Lee’s指数,取血、肝脏检测相关生化指标。结果：与C组比较,H组Lee’s指数,血清FFA、IL-6、TNF-α、TC、TG、LDL-c,肝脏FFA、IL-10显著升高（P<0.01）;血清HDL-c水平显著降低（P< 0.01）。与H组比较,HC、HM、HMC组Lee’s指数,血清FFA、IL-6、TNF-α、TC、TG、LDL-c,肝脏FFA、IL-10显著降低（P<0.05或P<0.01）;血清HDL-c水平显著升高（P<0.05或P<0.01）。与HC、HM组比较,HMC组Lee’s指数,血清FFA、IL-6、TNF-α、TC、TG、LDL-c,肝脏FFA、IL-10显著降低（P<0.05）;血清HDL-c水平显著升高（P<0.05）。结论：有氧运动和破壁蛋白核小球藻干预能够不同程度改善高脂膳食大鼠脂代谢,降低肥胖对肝脏造成的脂毒性。其中联合干预较单一干预更为有效。     

Adipophilin在动脉粥样硬化病变和脂质负荷细胞中的作用研究(英文)

Adipophilin是细胞内脂质聚集和与脂质聚集有关疾病的标志物 ,巨噬细胞源性泡沫细胞的形成是动脉粥样硬化性疾病发生的重要环节 .为了探讨adipophilin在动脉粥样硬化性疾病的作用 ,通过高胆固醇饲料喂养新西兰白兔 12周 ,复制动脉粥样硬化疾病模型 ,同时测定血脂的变化和动脉壁胆固醇 ,使用HE染色、苏丹Ⅳ染色观察动脉粥样硬化病变的形成 ,使用免疫组织化学的方法观察动脉粥样硬化病变处和动物肝脏中adipophilin的表达 .结果发现 ,高胆固醇饲料喂养组血清总胆固醇、低密度脂蛋白胆固醇和动脉壁胆固醇明显增高 ,动脉粥样硬化病变面积增加到 (40 0 6± 7 2 9) % ,动脉粥样硬化病变处adipophilin表达呈阳性 ;而adipophilin在肝脏中的表达无论是高胆固醇饲料喂养组或对照组均为阴性 .使用80mg/L OxLDL与小鼠腹膜巨噬细胞共孵育 ,复制脂质负荷细胞 ,然后把构建的 1mmol/Ladipophilin反义寡核苷酸与该细胞共孵育 .结果发现 ,使用油红O染色观察的细胞内脂滴明显减少 ,生化测定细胞内胆固醇酯显著降低 ,与对照组相比 ,差别有显著性 .说明adipophilin与动脉粥样硬化病变有密切的关系 ,控制adipophilin的表达能够减少巨噬细胞细胞内胆固醇酯的聚集     

银灵通胶囊调节实验性高脂饮食大鼠血脂的研究

目的:探究银灵通胶囊对脂质代谢的影响及其机制。方法:建立大鼠高脂模型,用药后检测其血脂、丙二醛(MDA)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)的活性,检测肝脏组织的高密度脂蛋白受体SR-BI、低密度脂蛋白受体(LDLR)、氧化低密度脂蛋白(ox-LDH)受体CD36蛋白表达的mRNA表达水平,检测血管组织学变化。结果:高脂饮食明显升高大鼠血清中总胆固醇(CH)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)和动脉硬化指数(AI值),银灵通胶囊组可降低上述指标,且呈一定的浓度依赖;高脂饮食可增加肝脏中SR-BI及CD36表达,降低LDLR表达,银灵通胶囊引起SR-BI的过度表达,使LDLR表达增加,CD36表达下降。高脂饮食使血清中MDA的含量增加,给予银灵通胶囊后,明显降低血清MDA的含量。结论:银灵通胶囊具有调节脂质代谢,抗动脉粥样硬化(AS)及抗脂质过氧化作用。其机制与银灵通胶囊能引起肝脏中SR-BI的过度表达及LDLR表达增加,降低肝脏中CD36表达和血清MDA含量有关。     

Effects of dietary medium-chain triacylglycerols on serum lipoproteins and biochemical parameters in healthy men

The objective of this study was to investigate effects of dietary medium-chain triacylglycerols (MCTs) on serum lipid levels, liver function, and hepatic fat accumulations in healthy men. Eleven subjects consumed 2200-2600 kcal daily, of which 70-80 g was fat; the fat included 40 g of MCTs or else 40 g of long-chain triacylglycerols (blended vegetable oil). The diet was followed for 4 weeks in this controlled double-blind study. At the end of the experiment, significant differences were not found in the concentrations of serum total cholesterol, very low density lipoprotein cholesterol, low density lipoprotein cholesterol, and high density lipoprotein cholesterol between the groups. Serum triglycerol levels were not significantly different in the groups. Adverse effects from ingestion of MCTs on liver functions, the liver-to-spleen ratio on computed tomography (an index of fatty liver), or results of blood tests were not seen. The results suggest that the long-term effects of dietary MCTs on serum cholesterol were similar to those of unsaturated fatty acids found abundantly in vegetable oil, and that consumption of MCTs in the amount of 40 g/day for a month does not cause liver fat accumulation or liver dysfunction.     

Effect of long term feeding of rice bran oil upon lipids and lipoproteins in rats

The effects of feeding two levels of rice bran oil (RBO) on the growth, lipid parameters, and fatty acid composition of the plasma and liver of rats (Wistar strain) were compared with those produced on animals which had been fed the same levels of peanut oil (PNO). The control animals were fed synthetic diets containing 5 and 20% peanut oil (PNO) and the experimental groups were fed similar diets, containing the same level of rice bran oil (RBO). There was no significant difference with respect to the organ weights between the control and the experimental groups. In general, groups fed 20% oil gained more weight than groups fed 5% oil. The animals which received rice bran oil in their diet had, in general, comparatively lower levels of cholesterol, triglycerides and phospholipids. On the other hand, animals receiving 20% rice bran oil in their diet, showed an increase of 20% in high density lipoproteins (HDL-C), within 18 weeks (p<0.05), when compared to the animals fed with peanut oil. Similarly, low density lipoprotein cholesterol (LDL-C) and very low density lipoprotein cholesterol (VLDL-C) were lower in RBO-fed groups, than in the PNO-fed groups. There was, however, no significant differences in the cholesterol/phospholipid (C/P) ratio of the two groups. Analysis of plasma and of liver fatty acids indicated, in a general way, the type of fat consumed. There were no significant difference in the P/S ratio, nor any in the oleic/linoleic, oleic/stearic, palmitoleic/palmitic, oleic/palmitic, and oleic/palmitoleic ratios. Furthermore, levels of saturated (SAFA), monounsaturated (MUFA), and polyunsaturated (PUFA) fatty acids were identical in both the groups. Thus, our results suggest that feeding a high level of rice bran oil (RBO) has no deleterious effect on the growth and blood lipid profile of rats.Abbreviations PNO peanut oil - RBO rice bran oil - HDL-C high density lipoprotein cholesterol - LDL-C low density lipoprotein cholesterol - VLDL-C very low density lipoprotein cholesterol - SAFA saturated fatty acids - MUFA mono-unsaturated fatty acids     

Selenium-Enriched Probiotics Improves Murine Male Fertility Compromised by High Fat Diet

A total of 75 male mice were allotted to five groups of 15 each in a completely randomized experimental design to study the effects of probiotics, inorganic selenium, and selenium-enriched probiotics on male fertility in hyperlipidemic status. The mice in group 1 were fed a normal basal diet and served as negative control. The mice in group 2 were fed a high fat diet and served as positive control. The mice in groups 3, 4, and 5 were fed the high fat diet supplemented with probiotics, inorganic selenium, and selenium-enriched probiotics, respectively. The high fat diet was composed of 15% lard, 1% cholesterol, 0.3% cholic acid, and 83.7% basal diet. Over 90% of the selenium in the selenium-enriched probiotics was present in forms of organic selenium. After the mice were fed these diets for 75 days, serumal total cholesterol, triglycerides, low density lipoprotein, high density lipoprotein, and testosterone levels, plus sperm index (count, motility and abnormalities), penis length, and weight and histopathology of testes were measured. The results showed that in the mice fed the high fat diet were significant (P < 0.01) elevations of serumal total cholesterol, triglycerides and low density lipoprotein, and decreases of high density lipoprotein. The high fat diet caused a decline in serumal testosterone level, reduced semen quality, and atrophy and degeneration of seminiferous tubules. No effects on penis length or relative weight of testis were observed. Supplementation of probiotics, inorganic selenium, or selenium-enriched probiotics to the high fat diet significantly alleviated (P < 0.05) the adverse effects of hyperlipidemia by reducing testicular tissue injury, increasing serumal testosterone level, and improving sperm indexes. It was concluded that hyperlipidemia had significant adverse effects on male fertility, which could be ameliorated at various degrees by feeding the diets supplemented with probiotics, inorganic selenium, or selenium-enriched probiotics. Selenium-enriched probiotics or inorganic selenium supplementation gave better results than probiotics supplementation and may be used to improve animal and human male fertility compromised by hyperlipidemia or obesity.     

Hypertriglyceridemia and delayed clearance of fat load in transgenic rabbits expressing human apolipoprotein CIII

Apolipoprotein CIII (apoCIII) has been implicated in hypertriglyceridemia and plasma apoCIII independently predicts risk for coronary heart disease. While hypertriglyceridemia in patients has been demonstrated to correlate with elevated plasma apoCIII levels and reduced lipoprotein lipase (LPL) activity, apoCIII transgenic mice show elevated LPL activity. In this study, we generated transgenic (Tg) rabbits expressing human apoCIII gene exclusively in liver and investigated the effect of apoCIII overexpression on lipid metabolism of rabbits. In comparison with non-Tg littermates, Tg rabbits had 3- and 3.2-fold increases in fed and fasted plasma triglycerides, respectively. In contrast, no significant differences were observed in plasma total cholesterol and high density lipoprotein cholesterol levels between Tg and non-Tg rabbits. Analysis of lipoprotein fractions revealed that elevated plasma triglyceride levels in Tg rabbits were mainly attributed to an increase in very low density lipoprotein/chylomicron-sized particles. Furthermore, Tg rabbits showed markedly delayed clearance of plasma triglycerides accompanied with significantly reduced LPL activity in post-heparin plasma compared to that in non-Tg controls. In conclusion, these results indicate apoCIII transgenic rabbits develop hypertriglyceridemia with similar mechanism in hypertriglyceridemic patients via delayed clearance of plasma triglycerides, and could be used as a valuable tool for the study of human hyperlipidemia in relation with atherosclerotic disorders.     

Reduction in plasma cholesterol and increase in biliary cholesterol by a diet rich in n-3 fatty acids in the rat

Cholesterol and lipoprotein metabolism were investigated in a group of rats fed a fish oil-supplemented diet, a rich source of n-3 fatty acids. For comparison purposes, other groups of rats were fed either safflower oil (n-6 fatty acids) or coconut oil (saturated fatty acids). Diets were isocaloric and contained identical amounts of cholesterol. Rats fed fish oils for 2 weeks showed a 35% lower plasma cholesterol level than rats fed safflower oil, who in turn showed a 14% lower plasma cholesterol level than those fed coconut oil. The fall in plasma cholesterol level with fish oils was associated with significant falls in low density and high density lipoprotein cholesterol levels, but with no significant change in the ratio of low density to high density lipoprotein cholesterol. The fatty acid compositions of plasma, hepatic, and biliary lipids showed relative enrichment with n-3 fatty acids, reflecting the composition of the diet. The fish oil diet increased the basal secretion rate of cholesterol into bile, but the bile acid secretion rate remained unchanged. It is suggested that n-3 fatty acids reduce the plasma cholesterol level in rats by increasing the transfer of cholesterol into bile.