旋毛虫感染对高脂饮食肥胖小鼠的干预作用

流行病学分析显示,蠕虫感染率和肥胖等代谢疾病呈负相关,然而其作用机制未被完全阐明。本文探究了旋毛虫(Trichinella spiralis)感染对高脂饮食(HFD)肥胖小鼠的干预作用,并初步分析其作用机制。以高脂饮食构建肥胖模型,分为3 组：ND组给予基础饲料,其他两组高脂饲喂。4 周后,HFD+inf组口服感染250 条肌肉虫期旋毛虫,各组继续饲喂8周。每周称重,实验末期统计肝脏和附睾脂肪湿重;检测血清总胆固醇(TC)和甘油三酯(TG)含量;HE染色观察附睾脂肪组织病理学形态;油红O染色观察肝脏组织内脂滴情况;荧光定量PCR方法分析附睾脂肪中脂代谢基因表达。结果显示,与HFD组比较,HFD+inf组体重增加明显降低,血清中TC和TG的升高程度有所降低;HE显示附睾脂肪细胞的体积增大得到改善;同时,小鼠肝脏质量增加呈现降低趋势,油红O染色可见肝脏脂质变性得以纠正;此外,旋毛虫感染还可下调附睾脂肪组织中脂质合成相关基因并且上调脂质分解相关基因的mRNA表达水平。结果表明,旋毛虫可以通过减少机体脂质累积和加速脂质分解来影响脂质代谢,从而有效干预高脂诱导的肥胖,因此旋毛虫及其抗原可能为防治...     

3T3-L1前脂肪细胞诱导分化方法的建立

小鼠3T3-L1前脂肪细胞是目前研究脂肪相关疾病和脂肪沉积最常用细胞模型之一。本研究拟建立小鼠3T3-L1前脂肪细胞培养及诱导分化为成熟脂肪细胞的方法。采用油红O染色法对诱导分化成熟的脂肪细胞染色,镜下观察到在诱导分化后的7、8、9、d均有明显的脂质沉积,脂滴被油红O着染成鲜亮的橘红色,脂滴大小和数量均表现出逐渐增加的趋势。采用Real-time qPCR检测在3T3-L1前脂肪细胞的分化和脂质积累过程起重要调控作用的ADIPOQ和C/EBPα两个因子的相对表达量。结果表明:在小鼠3T3-L1前脂肪细胞的分化成熟阶段,随分化时间的延长ADIPOQ和C/EBPα在3T3-L1前脂肪细胞的脂质高度累积阶段分别呈现出逐渐降低和增加的趋势。通过形态学和分子生物学手段检测结果表明,本实验方法成功地将小鼠3T3-L1前脂肪细胞诱导为成熟的脂肪细胞。     

C57BL/6J小鼠非酒精性脂肪肝模型的建立

本试验分别采用高脂饲料和高脂饲料复合四氯化碳对C57BL/6J小鼠进行诱导,研究建立非酒精性脂肪肝模型的条件.本试验将C57BL/6J小鼠分成高脂组、高脂复合四氯化碳组(复合组)和正常组.各组分别于饲喂4、6、8周处死5只,称小鼠体重与肝重,采血测血清中生化指标情况,并取肝脏做H.E.染色、油红O染色.通过肝指数、生化与病理检查等指标,评价非酒精性脂肪肝的进程.结果显示,随着饲喂时间加长,高脂组动物肝脏脂肪变性加重;复合组动物除肝脏脂肪变性外,出现纤维化和明显的炎性浸润;4周时,高脂组中脂肪变性比复合组明显.6～8周时高脂组和复合组中生化指标明显高于正常组.本试验经饲喂高脂饲料成功复制了小鼠非酒精性脂肪肝模型.     

兔腹主动脉粥样硬化模型的建立

为建立兔腹主动脉粥样硬化模型,将60只新西兰大耳白兔随机分为高脂饲料和普通饲料两组喂养每组30只,定期测量体重和血脂类指标,18周处死动物,观察腹主动脉形态结构。结果表明,高脂饲料兔血脂类指标升高,血管内壁脂质沉积,镜下见内皮细胞脱落缺失,多层泡沫细胞堆积,平滑肌细胞减少或增生,弹力蛋白和胶原糖蛋白基质成分增多等改变,表明动物模型建立成功。     

棕榈酸通过上调ACC/FAS/DGAT2通路表达诱导BRL 3A细胞脂肪变性

为探究棕榈酸诱导BRL 3A细胞脂肪变性的机制,以不同浓度的PA（0、0.2、0.4、0.6 mmol·L^-1）处理BRL 3A细胞24 h,用CCK-8法、RTCA技术检测细胞增殖情况;油红O染色,观察细胞脂滴生成情况;DAPI/F-actin双染,观察细胞核及骨架形态;采用比色法测定TG含量;采用RT-PCR检测脂肪合成相关基因Acaca、Fasn、Dgat2转录水平;采用Western blot检测脂肪合成关键蛋白ACC、FAS、SCD1、GPAM、DGAT2表达量。结果显示：与对照组相比,0.2、0.4 mmol·L^-1 PA对细胞增殖无影响,0.6 mmol·L^-1 PA抑制细胞增殖;油红O染色结果显示0.4 mmol·L^-1 PA处理细胞24 h,脂滴大量蓄积,发生明显脂肪变性;随PA浓度升高,细胞核发生皱缩、变形、碎裂,细胞骨架被破坏,微丝断裂;TG含量极显著增加（P<0.01）;不同浓度PA（0.2、0.4、0.6 mmol·L^-1）处理组脂肪合成关键基因Acaca、Fasn、Dgat2 mRNA转录水平均显著升高（P<0.05）,ACC、FAS、SCD1、GPAM、DGAT2蛋白表达水平均显著升高（P<0.05）;0.6 mmol·L^-1 PA组与0.4 mmol·L^-1 PA组相比,SCD1蛋白表达水平显著降低（P<0.05）。高浓度棕榈酸抑制BRL 3A细胞增殖,对细胞核及骨架产生损伤;棕榈酸诱导细胞发生脂滴蓄积,TG增加,通过上调脂肪合成关键基因Acaca、Fasn、Dgat2 mRNA转录水平及ACC/FAS/DGAT2通路蛋白表达水平诱导细胞发生脂肪变性。     

糖尿病动脉粥样硬化兔模型的建立

建立兔糖尿病动脉粥样硬化模型。四氧嘧啶静脉推注诱发糖尿病后,行腹主动脉球囊损伤术拉伤内皮并饲高脂饲料建立糖尿病动脉粥样硬化兔模型,喂养10周做腹主动脉造影和腹主动脉内超声后处死,取腹主动脉横切片做HE染色和免疫组化,以评价动脉粥样硬化病变的程度和性质。糖尿病动脉粥样硬化形成。糖尿病动脉粥样硬化兔的腹主动脉粥样硬化病变内有更加活跃的炎症细胞浸润,提示病变性质不稳定。     

FGF21对NEFA介导肝脂质沉积及AMPK调控因子的影响特征

研究旨在阐明成纤维细胞生长因子21（FGF21）对AMPK磷酸化调控因子的影响机制,并明确FGF21对高NEFA介导的小鼠肝细胞脂滴代谢的影响特征。对AML12小鼠肝细胞进行添加NEFA和（或）沉默FGF21处理,应用荧光定量PCR技术检测肝细胞FGF21、肝激酶B1（LKB1）、转化生长因子β激活激酶1（TAK1）、钙调蛋白依赖性蛋白激酶（CaMKK）mRNA表达水平;用油红O染色检测肝脂沉积水平。结果显示,沉默FGF21,显著（P<0.05）降低LKB1表达,而对TAK1、CaMKK表达量没有显著（P>0.05）影响。高浓度NEFA下,沉默FGF21肝细胞脂质沉积水平显著增高。由该试验结果可以得出,高NEFA下肝细胞FGF21可能通过诱导LKB1激活AMPK信号通路,进而减少肝细胞脂质沉积。     

柞蚕雄蛾油对大鼠辅助降血脂功能的影响研究

为研究柞蚕雄蛾油对小鼠血脂代谢的影响,进行了雄性Wistar大鼠高脂饲料与不同剂量柞蚕雄蛾油的喂养试验,每4天称体重一次,每4天测定小鼠肝系数及血清总胆固醇（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）一次。结果表明：3个剂量组TC、TG、LDL‐C含量与高脂模型组比较显著低于高脂模型组,而HDL‐C显著高于模型组,具有显著性差异（P＜0．05）。     

C57BL/6NcGAS基因敲除鼠的构建及对猪伪狂犬病病毒增殖的影响

胞质DNA感受器环鸟苷酸-腺苷酸合成酶(cyclic GMP-AMP synthase, cGAS)能够识别胞质中的双链DNA(double stranded DNA,dsDNA),从而激活Ⅰ型干扰素信号通路抵御外界病原微生物的感染。为研究cGAS基因对猪伪狂犬病病毒(PRV)增殖的影响，本试验首先利用CRISPR/Cas9基因编辑技术构建cGAS基因敲除小鼠，通过H&E染色检测C57BL/6N小鼠和C57BL/6N-cGAS^-/-小鼠肺脏和脑组织形态差异及感染PRV后肺脏组织中炎性浸润的影响；Q-PCR检测C57BL/6N小鼠和C57BL/6N-cGAS^-/-小鼠感染PRV后对PRV-gB、PRV-TK、IFN-β、ISG15和ISG20基因mRNA表达水平的差异；Western blot及免疫组化检测C57BL/6N小鼠和C57BL/6N-cGAS^-/-小鼠感染PRV后PRV-gB和PRV-gE蛋白表达水平；最后利用病毒PFU法检测cGAS敲除鼠对PRV子代病毒滴度的影响。Western blot检测结果显示...     

番鸭产蛋各期肝脂肪酸组成及AMPK信号通路基因表达研究

旨在探究产蛋各期番鸭肝腺苷酸活化蛋白激酶（AMPK）信号通路基因表达和肝脂肪酸组成,为番鸭肝脂质代谢应答产蛋提供机理研究。本研究选取开产前22周龄、产蛋初期30周龄、产蛋中期40周龄和产蛋末期60周龄母番鸭各15羽,全自动生化仪测定血脂水平,苏木精-伊红（HE）染色和油红O染色观察肝组织学结构,实时荧光定量PCR （qRT-PCR）检测肝AMPK通路基因表达,气相色谱-质谱联用法（GC-MS）检测产蛋各期肝脂肪酸组成。结果表明,总胆固醇（TC）、低密度脂蛋白胆固醇（LDL-C）、甘油三酯（TG）和极低密度脂蛋白胆固醇（VLDL-C）水平在40周龄显著高于22、30和60周龄（P<0.05）;高密度脂蛋白胆固醇（HDL-C）水平在30和40周龄显著低于22和60周龄（P<0.05）。肝HE和油红O染色切片显示,肝在22周龄呈实质状,至产蛋40和60周龄,肝脂滴沉积明显（P<0.05）。AMPKα1在22、30、40和60周龄呈本底低水平表达,并显著低于产蛋各期肉碱脂酰转移酶1（CPT1）和脂肪酸合成酶（FAS）的表达量（P<0.05）,FAS在22、40和60周龄均呈高水平表达（P<0.05）;羟甲基戊二酰辅酶A还原酶（HMGR）、肝细胞核因子4α（HNF4α）、乙酰辅酶A羧化酶1（ACC1）和固醇调控元件结合蛋白-1（SREBP1c）在40周龄表达量显著高于22和30周龄（P<0.05）。肝中饱和脂肪酸（SFA）、单不饱和脂肪酸（MUFA）和多不饱和脂肪酸（PUFA）主要由C16∶0、C18∶0、C18∶1和C20∶2 n-6构成,分别占总脂肪酸含量的32%、16%、30%和9%。C14∶0和C16∶0含量在40周龄显著高于22周龄（P<0.05）;C24∶0、C20∶2 n-6和PUFA含量在60周龄显著高于22和40周龄（P<0.05）。综上,番鸭产蛋期肝通过上调FAS等脂质合成基因表达,合成大量长链脂肪酸,沉积于肝,并增加血脂水平。     

Echocardiographic characterisation of cardiac dilatation induced by volume overload in a canine experimental model

The aim of this study was to characterise the development of cardiac dilatation induced by chronic volume overload in 12 dogs. Bilateral arteriovenous fistulas were created between the common femoral arteries and the femoral veins, and the animals were serially studied with transthoracic echocardiography for a period of 12 weeks after the operation. Compared to the measurements obtained before the operation (week 0), the data obtained at the end of the experimental period showed significantly increased left ventricular volume measured by 2D-echocardiography (from 25.1 cm3 to 43.8 cm3, p < 0.0001 in diastole and from 8.6 cm3 to 16.8 cm3, p < 0.001 in systole), and left ventricular diameter measured by M-mode echocardiography (from 26.2 mm to 32.6 mm, p < 0.0001 in diastole and from 17.1 mm to 20.6 mm, p < 0.001 in systole). The size of the left atrium also increased in transversal (from 29.2 mm to 33.6 mm, p < 0.01) but not in longitudinal diameter. In spite of a significant cardiac chamber dilatation over the 12-week period, left ventricular systolic functional variables (fractional shortening, FS % and ejection fraction, EF %), and also the left ventricular systolic and diastolic free wall thickness remained unchanged. In this study we demonstrated that chronic progressive volume overload resulted in gradual dilatation of the canine heart, and that the pathological process can be monitored successfully by serial echocardiography. We found that left atrial dilatation occurred without the development of mitral regurgitation and/or detectable left ventricular dysfunction.     

Echocardiographic characteristics of chickens with ascites syndrome

1. B- and M-mode echocardiography was used to compare cardiac function in broilers with spontaneous ascites syndrome with that of normal chickens. 2. Thirty ascitic chickens and 15 normal chickens aged three, 4, 5, and 6 weeks from the same flock (180 birds in total) were examined. They were restrained gently in a natural standing position, and echocardiographs were obtained from a 7.0-MHz linear transducer placed on the left pectoral apterium. Indices of cardiac structure and functioning were calculated from the echocardiographs, and some were normalised to body weight. Heart rate was also measured. 3. All cardiac structural indices in both ascitic and normal chickens increased with age. Compared with normal chickens, right ventricular diameter at the end of systole in ascitic chickens was greater at 4, 5 and 6 weeks of age. Ventricular septal thickness at the end of both systole and diastole was greater in ascitic chickens at 5 and 6 weeks. Left ventricular free wall thickness at the end of diastole was less in ascitic chickens at 3 weeks. However, all the structural indices decreased with age after normalisation with body weight. 4. The heart rate of ascitic chickens was lower at 4, 5 and 6 weeks. Normalised left ventricular fractional shortening was lower in ascitic chickens at 4, 5 and 6 weeks, as was normalised right ventricular fractional shortening. Incrassation of the ventricular septum (Delta T), which changed little in normal chickens, was less at 4, 5 and 6 weeks in ascitic chickens. Left ventricular fractional shortening, right ventricular fractional shortening and Delta T were all negatively correlated with ascites heart index at all ages. 5. Taken together the results suggest heart failure of both ventricle, but that right ventricular dysfunction is more extensive than left ventricular dysfunction. We suggest that secondary pulmonary hypertension would result in these ascitic chickens due to volume overload.     

Pathophysiologic mechanism of cardiac dysfunction in experimentally induced heartworm caval syndrome in dogs: an echocardiographic study

In dogs with experimentally induced heartworm infection, the onset of caval syndrome (CS) was characterized by a murmur, loudest over the tricuspid valve, and a large worm mass in the right ventricular lumen detectable during diastole by use of M-mode echocardiography. Two-dimensional echocardiography indicated that the worm mass was located in the right atrium and venae cavae and was "flowing" into the right ventricle during rapid diastolic filling. Paradoxical septal motion and vigorous right ventricular cranial wall motion also were observed. Other echocardiographic changes included decreased size of the left atrium and ventricle, aortic root, and ratio of left-to-right ventricular diastolic luminal diameter, compared with values obtained 6 months after experimentally induced heartworm infection. Right ventricular end diastolic diameter increased considerably. Most echocardiographic indices of left ventricular function (fractional shortening, velocity of circumferential fiber shortening, ejection fraction, and preejection period) were not altered appreciably, but estimates of cardiac index and stroke volume were markedly decreased. Electrocardiography revealed ventricular and supraventricular premature complexes in 7 of the 8 dogs studied, evidence of right ventricular enlargement in 6 of the 8 dogs studied, and increased mean heart rate, compared with that measured 6 months after inoculation of infective larvae, before the onset of CS. Cardiac catheterization was performed in 3 days at the onset of CS. Severe pulmonary arterial and right ventricular hypertension and decreased cardiac index (compared with values obtained before inoculation) were observed. Evidence of right ventricular inflow obstruction was not detected. Mean aortic blood pressure decreased with the onset of CS, but right ventricular end diastolic pressure increased.(ABSTRACT TRUNCATED AT 250 WORDS)     

Echocardiographic evaluation of equine aortic insufficiency

Echocardiographic evaluation of 23 horses with aortic insufficiency was performed, using M-mode (n = 23) and 2-dimensional real-time echocardiography (n = 14 of 23). Echocardiograms were evaluated for abnormalities of aortic and mitral valves and alterations in motion of these valves. Changes in left ventricular chamber size and function, as well as aortic root size, were evaluated. The presence of other cardiac disease was also evaluated. Horses with aortic insufficiency had significant increases (P less than 0.01) in mean values of left ventricular chamber size, aortic root diameter, and shortening fraction. Left ventricular free wall thickness also was significantly decreased (P less than 0.01). Valvular abnormalities were seen echocardiographically in all 23 horses. Eighteen horses with aortic insufficiency had thickened valves, whereas two horses had lesions associated with vegetative endocarditis. High-frequency vibrations of the septal leaflet of the mitral valve were noticed in all horses, whereas similar vibrations of the aortic valve were seen in six horses. The presence of a bounding arterial pulse correlated significantly (P less than 0.05) with increased left ventricular chamber size at end diastole and shortening fraction, indicating a marked left ventricular volume overload. A reliable diagnosis of aortic insufficiency can be made with the detection of bounding arterial pulses in concert with a holodiastolic decrescendo grade II to V/V murmur with maximal intensity over the aortic valve area, radiating toward the left cardiac apex.     

Growth,behavioural, serum biochemical and morphological changes in female rabbits fed high-fat diet

This study aimed to determine whether high-fat diet (HFD) could cause growth, behavioural, biochemical and morphological changes in young female rabbits. Thirty-six female rabbits were randomly divided into two groups fed with either a high-fat diet (HFD) or a standard normal diet (SND) for 5 weeks. Growth and behavioural changes were recorded during the 5-week feeding period. Tissue samples, including blood and adipose tissue, were obtained after slaughter. HFD rabbits weighed more by the end of the feeding period, had a higher percent body weight and adipose tissue weight change and had longer body and bust lengths than SND rabbits. HFD rabbits significantly reduced their feed intake and feeding frequency during the fourth and fifth weeks. HFD rabbits also showed lower frequency of drinking and resting and increased stereotypical behaviour. Besides, HFD rabbits showed significant physiological abnormalities. HFD rabbits had higher serum cholesterol (TC) and triglycerides (TG) levels than SND rabbits at the end of the feeding period, and higher free fatty acid (FFA) levels than rabbits in the SND group after the third week of feeding. Serum thyroxine (T4) increased significantly in week 2 and week 5 and triiodothyronine (T3) increased significantly in week four. However, there was no significant change in serum glucose (GLU) and insulin (INS) levels. Additionally, HFD reduced the area and diameter of perirenal and subcutaneous fat cells and increased their density. Our findings suggest that HFD rabbits had higher weight gains, accumulation of fat, and more behavioural changes than SND rabbits. Although high levels of fat in the diet had a low impact on hyperglycaemia, it could lead to hyperlipidemia and hyperthyroidism. Our results also suggest that sustained HFD may cause the proliferation of adipocytes in young female rabbits.     

M-mode and Doppler echocardiographic reference values for male New Zealand white rabbits

OBJECTIVE: To determine M-mode and Doppler echocardiographic reference values in healthy New Zealand white rabbits. ANIMALS: 52 healthy male rabbits. PROCEDURES: The rabbits were anesthetized and M-mode measurements of the left ventricle, left atrium, and aorta and Doppler measurements of pulmonary and aortic outflow and mitral inflow were recorded. RESULTS: Mean +/- SD heart rate during echocardiographic examination was 155 +/- 29 beats/min. Mean +/- SD measurements in diastole and systole for the interventricular septum thickness, left ventricular internal diameter, and left ventricular free wall thickness were 2.03 +/- 0.37 mm and 3.05 +/- 0.45 mm; 14.37 +/- 1.49 mm and 10.25 +/- 1.22 mm; and 2.16 +/- 0.25 and 3.48 +/- 0.55 mm, respectively. Mean +/- SD left atrial-to-aortic diameter ratio was 1.17 +/- 0.14, and mean +/- SD mitral valve E-point-to-septal separation interval was 1.71 +/- 0.29 mm. Mean +/- SD for fractional shortening and ejection fraction were 30.13 +/- 2.98% and 61.29 +/- 4.66%, respectively. Mean +/- SD maximal aortic and pulmonary artery outflow velocities were 0.85 +/- 0.11 m/s and 0.59 +/- 0.10 m/s, respectively, and the peak E-to-peak A wave velocity ratio of the mitral valve was 2.19 +/- 0.46. CONCLUSIONS AND CLINICAL RELEVANCE: Results provide echocardiographic reference values for young adult male New Zealand white rabbits anesthetized with ketamine and medetomidine. Values obtained from unanesthetized rabbits, rabbits sedated with other agents, or rabbits of different size may differ from those reported here.     

A morphometric study of foetal and newborn cardiac growth in the horse

A morphometric study of hearts in 81 equine foetuses, ranging in age from 190 to 330 days of foetal age, and in 26 newborn foals is reported. The mean weight, external dimensions, ventricular wall thickness and circumference of the atrio-ventricular orifice were measured. Features of the main associated vessels of the heart were also recorded. All cardiac measurements of foetuses increased linearly throughout the latter half of pregnancy and were highly correlated with foetal age. This linear growth pattern was also found in the parameters of the associated arterial trunks. The ratio of the right ventricular weight to the total ventricular weight in the equine foetuses increased gradually from 0.27 (Day 190) to 0.34 (full term), but in newborn foals, this ratio began to decrease soon after birth, declining from 0.32 to 0.28 by 11 days of age. The interventricular septum was thickest followed by the right ventricular wall, and the left ventricular wall was thinnest during the period of gestation studied. The right ventricle was 3.2 per cent to 31.5 per cent thicker than the left ventricle.     

DHA对高脂饲粮诱导肝脏脂肪积累的预防作用

【目的】探索二十二碳六烯酸(DHA)对高脂饲粮诱导肝脏脂肪积累的预防机制。【方法】将32只雄性SPF级C57BL/6小鼠均分为4组,对照组(Con)饲喂普通饲粮,模型组(Model)饲喂高脂饲粮,DHA组分别在高脂饲粮中添加0.2 g DHA(DHAL)和1.0 g DHA(DHAH),饲喂周期为20周。饲喂期间每天称量体重及食物重量,计算摄食量;饲喂结束,采集肝脏和血液,ELISA法检测肝脏脂联素和血清甘油三酯(TG)的含量,实时荧光定量PCR检测新生脂肪合成关键酶(SREBP-1c、FAS)、脂肪酸氧化关键基因(PPARα、PPARγ、CPT-1A和ACOX)、线粒体基因(PGC-1α)、褐色脂肪化基因(Prdm16、UCP1)的表达,Western blotting法检测肝脏磷酸化ACC、AMPK和AKT蛋白的表达。【结果】与Con组相比,Model组终体重、体脂重量和TG含量均显著增加(P<0.05),肝脏脂联素浓度显著降低(P<0.05)。与Model组相比,DHAL和DHAH组终体重、体脂重量和TG含量均显著降低(P<0.05),肝脏脂联素水平显著增加(P...     

M-mode echocardiographs of endurance horses in the recovery phase of long-distance competition

M-mode echocardiographic structures, and cardiac function indices, PCV, and total plasma protein values were determined for 34 endurance equine athletes before (base line) and after (after race) a 161-km endurance competition and were compared. The PCV (base-line mean, 37%; after-race mean, 46%) and total plasma protein value (base-line mean, 6.9 g/dl; after-race mean, 7.5 g/dl) increased. Compared with base-line echocardiography, after-race echocardiography indicated an increase in heart rate, as determined from the simultaneous ECG recorded on the echocardiograph (base-line mean, 41 beats/min; after-race mean, 54 beats/min), and an increase in interventricular septal diastolic thickness (base-line mean, 28 mm; after-race mean, 33 mm). The septal thickening fraction (base-line mean, 59%; after-race mean, 38%), the left atrioventricular valve E to F slope (base-line mean, 224 mm/s; after-race mean, 175 mm/s), the left ventricular diastolic dimension (base-line mean, 99 mm; after-race mean, 86 mm), the fractional shortening of the left ventricle (base-line mean, 41%; after-race mean, 37%), the aortic root dimension (base-line mean, 63 mm; after-race mean, 58 mm), the caudal aortic wall excursion (base-line mean, 19 mm; after-race mean, 11 mm) and the left atrial diastolic dimension (base-line mean, 46 mm; after-race mean, 39 mm), decreased significantly (P less than 0.05). In base-line echocardiographs, late diastolic left atrioventricular valve motion was evident in 9 horses. The aberrant left atrioventricular valve motion was not evident in after-race echocardiographs. Seemingly, central vascular volume decreased in these horses during the recovery phase of severe strenuous endurance competition.     

长期饲喂高精料日粮对泌乳期山羊血液生化参数及组织中糖代谢相关基因表达的影响

为了研究长期饲喂高精料日粮对泌乳期山羊血液生化指标和糖代谢的影响,选择8只安装永久性瘤胃瘘管的健康经产泌乳中期山羊,分别饲喂精粗比为40∶60 (low concentrate, LC,n=4) 和60∶40 (high concentrate, HC,n=4)的日粮。实验期共8周,实验期间采集瘤胃液,血液;实验结束时采集肝脏,肌肉,脂肪组织置于液氮速冻后于-70℃保存待测。结果显示,饲喂高精料日粮2周后山羊瘤胃液pH显著降低,采食后瘤胃液pH持续低于5.8超过3 h,8周后瘤胃液pH升高维持在6.0以上,但仍低于LC组山羊。与LC组山羊相比较,HC组山羊血液中葡萄糖、游离脂肪酸含量均升高(P<0.05,P=0.071),谷草转氨酶含量有上升的趋势(0.05相似文献