Magnetic resonance imaging of hepatocellular carcinoma induced by diethylnitrosamine in Sprague-Dawley rats

Diethylnitrosamine (DENA) is able to induce various benign and malignant liver lesions in rats with a high success rate and a low mortality rate. It provides a more appropriate model that better simulates the various lesions occurring in humans than the usual model of tumor implantations. The aim of the present study was to evaluate MRI liver examination in Sprague-Dawley(SD) rats as a routine method to detect hepatocellular carcinoma (HCC) nodules induced by DENA and to follow up their growth. METHODS:Hepatic carcinogenesis was induced in 80 male SD rats using oral DENA solution. All animals were imaged for liver tumor detection with a 1.5 Tesla magnet (Siemens Sonata,Erlangen, Germany) using correspondence scan parameters and a radio-frequency knee coil. Macroscopic examinations were performed along the axial MRI sections to evaluate magnetic resonance imaging (MRI) findings, and histopathological assessment was also performed. RESULTS:No false negative results were obtained on MR images. Hepatic tumors in 72 rats were confirmed macro-scopically and 68 rats were detected by MRI till the 20th week. The smallest and the largest nodules detected by MRI were 2 mm and 37 mm in diameter respectively. The agreement rate of MRI with macroscopic observation was 39. 1% and 97. 4% respectively for 2 mm to 5 mm and more than 5 mm nodules. CONCLUSIONS:The hepatic tumor induced by DENA provides a more representative range of tumors for imaging diagnosis and interventional treatment. MRI is the best approach for scrutinizing pathological changes of rat livers in the period of observation.

Analysis of transcriptome sequencing of sciatic nerves in Sprague-Dawley rats of different ages

An aging-induced decrease in Schwann cell viability can affect regeneration following peripheral nerve injury in mammals. It is therefore necessary to investigate possible age-related changes in gene expression that may affect the biological function of peripheral nerves. Ten 1-week-old and ten 12-month-old healthy male Sprague-Dawley rats were divided into young（1 week old） and adult（12 months old） groups according to their ages. mRNA expression in the sciatic nerve was compared between young and adult rats using next-generation sequencing（NGS） and bioinformatics（n = 4/group）. The 18 groups of differentially expressed mRNA（DEmRNAs） were also tested by quantitative reverse transcription polymerase chain reaction（n = 6/group）. Results revealed that（1） compared with young rats, adult rats had 3608 groups of DEmRNAs. Of these, 2684 were groups of upregulated genes, and 924 were groups of downregulated genes. Their functions mainly involved cell viability, proliferation, differentiation, regeneration, and myelination.（2） The gene with the most obvious increase of all DEmRNAs in adult rats was Thrsp（log2 FC = 9.01, P 〈 0.05）, and the gene with the most obvious reduction was Col2 a1（log2 FC = -8.89, P 〈 0.05）.（3） Gene Ontology analysis showed that DEmRNAs were mainly concentrated in oligosaccharide binding, nucleotide-binding oligomerization domain containing one signaling pathway, and peptide-transporting ATPase activity.（4） Analysis using the Kyoto Encyclopedia of Genes and Genomes showed that, with increased age, DEmRNAs were mainly enriched in steroid biosynthesis, Staphylococcus aureus infection, and graft-versus-host disease.（5） Spearman＇s correlation coefficient method for evaluating NGS accuracy showed that the NGS results and quantitative reverse transcription polymerase chain reaction results were positively correlated（rs = 0.74, P 〈 0.05）. These findings confirm a difference in sciatic nerve gene expression between adult and young rats, suggesting that, in peripheral nerves, cells and the microenvironment change with age, thus influencing the function and repair of peripheral nerves.

Analysis of Behaviour Pattern in Sprague-Dawley Rats Using Microwave Techniques

This communication presents a new method of detecting the behaviour pattern in Sprague-Dawley (SD) rats based on the measurement of the dielectric properties of blood plasma at microwave frequencies at different periods of time. The microwave measurements were performed by rectangular cavity perturbation method in the S-band of microwave frequency with the blood plasma collected from normal rats (Controls) as well as chemically induced rats (Aβ). A change is observed in the dielectric properties of the Aβsamples but not the controls samples at the extended period of time. This measurement technique is simple and the collection of blood from the rats is nonsurgical in nature. These results prove a new method of diagnosing Alzheimer’s Disease (AD) using microwave techniques.

Sprague-Dawley大鼠胃肠道微生物区系的研究

为了揭示Sprague-Dawley大鼠胃肠道微生物群落组成情况,探究大鼠胃肠道不同区域的菌群差异,该研究采用16S rRNA基因序列技术,对Sprague-Dawley大鼠的胃、十二指肠、空肠、回肠、盲肠、结肠和直肠的肠腔内容物进行基因组测序和微生物组成分析。结果表明:Sprague-Dawley大鼠不同胃肠道区域的细菌群落组成不同;大肠样本的物种丰富度和多样性高于小肠样本;厚壁菌门是各肠道段的优势菌门,乳酸杆菌属是各肠道段的优势菌属;与小肠相比,大鼠大肠微生物菌群更稳定、多样。研究结果揭示了Sprague-Dawley大鼠的胃肠道微生物群落组成信息,为其作为动物模型的相关研究提供了理论依据。

Morphological characteristics of the lumbosacral spinal cord urogenital center in Sprague Dawley rats

BACKGROUND： Studies have demonstrated that selective innervation of the sacral nerve tract to the bladder plays an important role in bladder functional reconstruction following spinal cord injury. However, there are very few studies reporting detailed morphological characteristics of urogenital center and lumbosacral nerve roots. OBJECTIVE： To analyze the spinal cord segment of the lumbosacral spinal cord urogenital center, and to observe morphological characteristics. DESIGN, TIME AND SETTING： A neuroanatomical study was performed at the Laboratory of Neuroanatomy, Peking University Health Science Center between September 2007 and March 2008. MATERIALS： Horseradish peroxidase-conjugated cholera toxin B subunit （CB-HRP） was purchased from Sigma, USA; surgical microscope was purchased from Zhenjian Zhongtian Optical Instrument, Jiangsu Province, China; BCL-420 biological and functional experimental system was purchased from Taimeng Science and Technology, Sichuan Province, China. METHODS： A total of 36 adult, Sprague Dawley rats were randomly assigned to groups A （n = 10）, B （n = 10）, C （n = 10）, and D （n = 6）. CB-HRP （3%, 10-15 μL） was injected into the bladder detrusor muscle （group A）, external urethral sphincter （group B）, and perineal muscles （group C）, respectively. Rats in group D were not given any treatments. MAIN OUTCOME MEASURES： At 72 hours after CB-HRP injection, CB-HRP-positive neurons were analyzed in lumbosacral segments using 3, 3＇, 5, 5＇-tetramethylbenzidine staining and an Olympus optic microscope, while anatomical structures in the respective spinal nerve tract were observed using a surgical microscope. RESULTS： CB-HRP-positive neurons were distributed in the L6-S1 segments of the spinal cord, and neurons primarily innervating the bladder detrusor muscle were located at the sacral parasympathetic nucleus and the intermediolateral nucleus. In addition, neurons that primarily innervate the external urethral sphincter and perineal muscles were observed in the ventrolateral portion （Onuf＇s nucleus）. The lumbar-sacral nerve roots were composed of varying nerve tracts, Le., they were typically divided into 1-2 sub-bundles, and the sub-bundles were then divided into 2-3 tiny bundles. There were extensive fibro-connections between the rootlets. CONCLUSION： The urogenital center in Sprague Dawley rats was located in the L6 -S1 segments of the spinal cord, and the rootlets were clearly observed. Therefore, this rat experimental model could be utilized for highly selective anterior/posterior rhizotomy.

Reference values for selected hematological, biochemical and physiological parameters of Sprague‐Dawley rats at the Animal House, Faculty of Medicine, University of Colombo,Sri Lanka

Background: Lack of available reference values in a research setting under local conditions can be a drawback for beginners, as the accuracy of data from control samples cannot be checked at the beginning of a research project. This affects comparisons with data from test samples. To avoid these complications in their research projects,beginners tend to have a greater number of animals in the control group compared to test groups in order to have control group measurements within 2 SDs of the mean.Methods: As non-availability of reference values was a long-felt need, the described project was conducted in order to establish a reference database for selected haematological, biochemical and physiological parameters using apparently healthy Sprague-Dawley rats bred in the Animal House of Faculty of Medicine, University of Colombo(UCFM).Results: Differences in mean values of packed cell volume(PCV), mean corpuscular volume(MCV) and mean corpuscular hemoglobin concentration(MCHC), serum creatinine and blood glucose levels between the two genders were statistically significant. Lipid profile measurements did not differ significantly between genders, but mean and median values of triglycerides(TG) between male and female rats showed a difference of more than 10 mg/dL. The liver enzymes alkaline phosphatase(AP)and aspartate aminotransferase(AST) were also statistically significantly different between sexes. Despite wide variation in mean alanine aminotransferase(ALT)between sexes, the difference was not statistically significant.Conclusion: The findings of this project should support to a certain extent the"Reduction" aspect of the 3 Rs concept of Russell and Burch by reducing the number of Sprague-Dawley rats used in future research projects at UCFM.

成年Sprague-Dawley大鼠的睡眠结构和呼吸暂停分析

目的 :了解成年Sprague -Dawley大鼠生理状态下的睡眠结构以及清醒 /睡眠状态下的呼吸暂停情况。方法 :对每只SD大鼠进行 6h的睡眠呼吸监测。大鼠的皮质脑电、颈部肌电以及通过微压传感器记录到的呼吸信号经过多导生理仪放大 ,以波形形式在计算机上同步显示并储存。使用人机交互的方法进行脑电分期和呼吸暂停的判断。SAS软件分析数据。结果 :2 6只成年雄性SD大鼠的非快动眼睡眠期 (NREM)和快动眼睡眠期 (REM)分别占总睡眠时间的 (83 3± 7 1) %和 (16 2± 7 1) %。全部监测大鼠在睡眠中出现呼吸暂停 ,平均睡眠呼吸暂停指数 (AI)为 (11 5± 4 6 )次 /h。其中REM期的呼吸暂停最频繁。且叹息后呼吸暂停主要发生于NREM期 ,而自发呼吸暂停主要发生于REM期。结论 :成年SD大鼠具有与人类相似的睡眠结构 ,睡眠中发生的中枢性呼吸暂停现象及其表现特点也与人类SAS患者相似 ,可以作为研究睡眠呼吸暂停中枢发病机制的天然动物模型。

Sprague-Dawley大鼠外周血来源间充质干细胞的动员、分离培养及鉴定

目的：探讨Sprague—Dawley大鼠外周血来源间充质干细胞（mesenchymal stem cells，MSC）的动员、分离培养及鉴定方法，分析其表面标记和多向分化潜能，为运动创伤中的细胞治疗和组织工程产品培育提供新来源的、可以微创获得和自体细胞移植的种子细胞。方法：联合动员大鼠外周血MSC．采集腹主动脉外周血4ml。使用淋巴细胞分离液结合密度梯度离心方法分离外周血单核细胞，体外培养至第3代。于显微镜下观察其形态和生长状态。取第3代MSC，鉴定其表型并向成骨、成脂和成软骨诱导分化．以证明其干细胞的特性。结果：经淋巴分离液结合密度梯度离心方法分离培养的外周血单核细胞．3～5天可见少量长梭形细胞贴壁，7-9天见细胞成簇生长，并形成克隆集落。第3代细胞形态较均一．生长增殖良好；表达典型的MSC标记CD44和CD90，不表达造血干细胞标记CD34和CD45。成骨诱导21天后，茜素红和ALP染色阳性，有矿化结节形成。成脂诱导21天后，油红0染色阳性．细胞内有脂滴形成。细胞微团无血清成软骨诱导21天后。甲苯胺蓝染色阳性，细胞外有蛋白多糖分泌：免疫组织化学染色示，特异性软骨基质II型胶原表达阳性。结论：采用联合药物动员方法能促进干细胞向外周血释放，分离培养的外周血干细胞经鉴定为MSC，体外具备三系分化潜能，有望成为运动创伤中新的细胞治疗和组织工程产品培育的种子细胞来源。

基质细胞衍生因子-1/CXC族细胞因子受体4轴在缺氧预处理骨髓间充质干细胞移植促进Sprague-Dawley大鼠急性心肌梗死心脏功能恢复中的作用

目的观察缺氧预处理的同种异体骨髓间充质干细胞(MSCs)移植入受体后,基质细胞衍生因子(SDF)-1/CXC族细胞因子受体(CXCR)4轴在促进Sprague-Dawley(SD)大鼠急性心肌梗死(AMI)心脏功能恢复中的作用。方法对SD大鼠的MSCs进行体外培养、鉴定,并行缺氧预处理。128只SD大鼠被随机分入MSCs移植组(MSCs组)、缺氧预处理MSCs移植组(预处理MSCs组)、AMI组、假手术组,每组32只。MSCs组、预处理MSCs组和AMI组大鼠均予冠状动脉左前降支结扎造成AMI 10min后,预处理MSCs组大鼠在梗死区域、梗死区边缘局部共注射5×105/\mL经缺氧预处理的MSCs,MSCs组大鼠注射5×105/\mL MSCs,AMI组大鼠注射相同容量的0.9%氯化钠溶液。假手术组大鼠仅行开胸处理。造模前和造模后28d采用超声心动图测量左心室舒张末期内径(LVDd)、左心室收缩末期内径(LVDs)、左心室射血分数(LVEF)3项反映心脏功能的指标。分别于造模后1、7、14和28d每组各处死8只大鼠取其心脏组织行免疫组织化学、常规病理染色,计算心肌梗死面积百分比、梗死区心室壁厚度和心室肌内微血管密度(MVD)。采用实时定量PCR和免疫激光共聚焦定性、定量测定各组心肌组织内SDF-1和CXCR4的表达。结果造模后28d时超声心动图检测结果显示,预处理MSCs组、MSCs组、AMI组的LVDd和LVDs均显著长于假手术组(P值均<0.05),LVEF均显著低于假手术组(P值均<0.05);预处理MSCs组、MSCs组的LVDd和LVDs均显著短于AMI组(P值均<0.05),LVEF均显著高于AMI组(P值均<0.05);预处理MSCs组的LVDd和LVDs均显著短于MSCs组(P值均<0.05),LVEF均显著高于MSCs组(P<0.05)。造模后28d,预处理MSCs组、MSCs组的心肌梗死面积百分比均显著小于AMI组(P值均<0.05),预处理MSCs组显著小于MSCs组(P<0.05);预处理MSCs组、MSCs组左心室前壁厚度均显著厚于AMI组(P值均<0.05),预处理MSCs组显著厚于MSCs组(P<0.05)。造模后28d,预处理MSCs组、MSCs组、AMI组心肌梗死区的MVD定量和AMI组梗死边缘区的MVD定量均显著低于假手术组(P值均<0.05),预处理MSCs组、MSCs组梗死边缘区的MVD定量均显著高于假手术组(P值均<0.05),预处理MSCs组、MSCs组心肌梗死区和梗死边缘区的MVD定量均显著高于AMI组(P值均<0.05),预处理MSCs组心肌梗死区和梗死边缘区的MVD定量均显著高于MSCs组(P值均<0.05)。造模后1、7、14和28d,预处理MSCs组、MSCs组和AMI组的SDF-1和CXCR4蛋白荧光强度均显著高于假手术组(P值均<0.05),预处理MSCs组、MSCs组均显著高于AMI组(P值均<0.05),预处理MSCs组均显著高于MSCs组(P值均<0.05)。结论SD大鼠AMI区局部注射缺氧预处理的MSCs或MSCs后可使SDF-1和CRCR4在受损组织局部表达上调,同时心功能得到改善。SDF-1/CRCR4轴在心肌梗死区局部表达上调可能是缺氧预处理MSCs或MSCs移植后改善心脏功能的重要途径之一。

Combined Subchronic Toxicity of Bisphenol A and Dibutyl Phthalate on Male Rats

Objective To evaluate the combined subchronic toxicity of bisphenol A（BPA） and dibutyl phthalate（DBP） in male Sprague Dawley（SD） rats.Methods Forty 4‐week‐old male rats weighing 115‐125 g were randomly divided into BPA‐treated,DBP‐treated group,BPA＋DBP‐treated and control groups and fed with a soy‐ and alfalfa‐free diet containing 285.4 ppm BPA,285.4 ppm DBP,285.4 ppm BPA plus 285.4 ppm DBP,and a control diet,respectively,for 90 consecutive days.At the end of the study,the animals were sacrificed by exsanguination via the carotid artery under diethyl etherane aesthesia and weighed.Organs,including liver,kidneys,spleen,thymus,heart,brain,and testis underwent pathological examination.The androgen receptor（AR）,gonadotropin‐releasing hormone receptor（GNRHR）,and progesterone hormone receptor（PR） genes from the hypothalamus were detected by real‐time PCR.The biomedical parameters were analyzed.Results No significant difference was found in food intake,body weight,tissue weight,organ/brain weight ratio,and biomedical parameters among the four groups（P〉0.05）.However,BPA and DBP up‐regulated AR,PR and GNRHR expression levels in rats and showed a synergistic or an additive effect in the BPA＋DBP group.Conclusion The combined subchronic toxicity of BPA and DBP is synergistic or additive in male SD rats.

Keladi candik(Alocasia longiloba Miq.) petiole extracts promote wound healing in a full thickness excision wound model in rats

Objective: To investigate the wound-healing effect of Alocasia longiloba(A. longiloba) petiole extract on wounds in rats.Methods: Twenty-two male Sprague-dawley rats were randomly assigned to receive 10% solcoseryl gel, phosphate buffer saline, 50% ethanol, 95% ethanol and hexane extracts of A. longiloba at 1.5%, 3% and 6% doses, respectively. A full thicknesses wound(6 mm) was created on the dorsal of the rat; and all rats were applied with the extract solutions, 10% solcoseryl gel and phosphate buffer saline once a day topically until day 12. The wound was photographed on day 1, 6 and 12, and the percentage of wound contraction was calculated. On day 12, rats were sacrificed and histological examination of granulation tissue was carried out using haematoxylin & eosin and Masson's Trichrome stain to determine the wound healing effect.Results: In this study, 6% of 50% and 95% ethanol extracts of A. longiloba showed 82.50% and 82.32% wound contraction, respectively, and were comparable with 10% solcoseryl gel(82.30%). Meanwhile, phosphate buffer saline treated group showed the lowest wound contraction(69.86%). Histological assessment of wound treated with 6% of 95% ethanol extract of A. longiloba showed distinct epidermal and dermal layer, higher proliferation of fibroblast and more angiogenesis with collagen compared to other wound treated groups.Conclusions: A. longiloba petiole extracts have a wound healing potential and 6% of 95% ethanol extract of A. longiloba is more effective. Further studies are required to understand the wound healing mechanism of action of the extract.

Morphometric study on Leydig cells in capsulotomized testis of rats

AIM: To further clarify the changes occurred in the testicular capsulotomized rats. METHODS: In testicular capsulotomized and sham-operated rats, the cross sectional area, the nucleus diameter and the number of Leydig cells were morphologically analyzed by the Vidas Image Processing System connected to a microscope. RESULTS: In the capsulotomized animals, the cross sectional area of Leydig cells was gradually increased from 30 days onwards. There was no obvious change in the nucleus diameter of Leydig cells. However, The Leydig cell number was significantly increased from day 30 onwards. CONCLUSION: In rats, testicular capsulotomy may induce hyperplasia/hypertrophy of Leydig cells in the testis.

Sprague-Dawley大鼠自发性乳腺癌分子分型的动物实验研究

目的探讨Sprague-Dawley(SD)大鼠患有自发性乳腺癌的分子分型情况。方法选取20只无特定病原体级雌性4周SD大鼠。通过分析全部大鼠乳腺癌分子分型,找到自发性乳腺肿瘤相关分子分型特点。结果 Luminal A型(55.00%)乳腺癌大鼠显著高于Basal-like型、Luminal B型和Her-2过表达型(P均<0.05),其余三组差异无统计学意义(P均>0.05)。结论临床上除常规生化指标及影像学诊断以外,配合ER、Cerb B-2及PR检测对早期鉴别大鼠乳腺癌有积极意义。

Evaluation of the Haematinic Activities of Extracts of <i>Justicia secunda</i>Vahl Leaves in Red Blood Cells of Laboratory Rats

The use of plant parts (leaves, flowers, stems, barks, roots etc.) in traditional medicine is increasingly gaining ground in modern medicine, as plant sources have long been recognized as sources of secondary metabolites which can be used to treat a wide range of diseases. The effect of extracts of Justicia secunda leaves on red blood cells (RBC) count and haemoglobin (Hb) concentration was investigated in adult Sprague-Dawley rats to establish haematinic activity. Phenylhydrazine (PHZ)-induced anaemic rats were treated with water, methanol or ethyl acetate extracts at 200 mg/kg body weight. RBC counts and Hb concentration were analysed using a haematology analyser at 3-day intervals for 21 days. The extracts were compared with rats administered the haematinic tonic Feroglobin&reg;?and vehicle-treated (normal saline). Rats administered the water extract exhibited the most significant increase (P ) in the number of RBCs and Hb concentration compared with the vehicle-treated PHZ-induced anaemic rats. Rats administered the methanol extract followed with significant increase (P ) in RBC counts and Hb concentration (J. secunda leaves has excellent haematinic properties and this provides the pharmacological basis of its use in Ghanaian traditional medicine for the treatment of anaemia.

Effects of Extracellular ATP on Survival of Sensory Neurons in the Dorsal Root Ganglia of Rats

ATP was added to the cultured sensory neurons obtained from the dorsal root ganglia of the neonatal rats and PBS was added to serve as control. MTT assays were conducted to evaluate the survival and activity of the cultured neurons. And the silicone regenerative chamber was used after the sciatic nerve incision of the mature SD rat. 1 mmol/L ATP was injected into the left chamber and 0.09 % natrium chloride was injected into the right chamber as controls. The changes of nitric oxide synthase (NOS) activity in the corresponding dorsal root ganglia were measured histochemically and image analysis was also performed 4 days after the sciatic nerve injury. The results showed that extracellular ATP could enhance the survival of the neurons and the number of NOS positive neurons were significantly different between the ATP and control groups ( P <0.05). It was suggested that extracellular ATP had neurotrophic effect on neurons survival and could inhibit the NOS activity of the sensory neurons after the peripheral nerve incision, hence exerting the protective effect on the neurons, which was valuable for nerve regeneration after nerve injury.

Effect of Alligator Pepper on Litter Weight of Rats Fed on High Glycemic Index Diet

This study was carried out to find out if alligator pepper can prevent the development of fetal macrosomia in Sprague-Dawley rats fed with high glycemic index diet. Fifteen adult female Sprague-Dawley rats of proven fertility were acclimatized for a period of two weeks in a well-ventilated laboratory and fed with grower’s mash and water ad libitum. Thereafter, they were randomly placed in separate cages after which a male Sprague-Dawley rat of proven fertility was introduced into each of the cages containing the female rats. They were left in the cages for three days during, which mating was confirmed to have occurred. The male rats were then withdrawn from the female rats, which were placed in separate maternity cages. The female rats were randomly allocated to three groups A, B and C so there were 5 pregnant rats in each group. The rats in group A were fed with 50 g of grower’s mash daily while the rats in groups B and C were fed with 50 g of cooked fermented cassava respectively. All rats were given water ad libitum throughout the duration of the experiment. The rats in groups A and B were intraperitoneally injected with 13.3 ml per Kg body weight of distilled water while the rats in group C were intraperitoneally injected with 13.3 mg/Kg body weight of aqueous extract of alligator pepper respectively. They were observed for 18 - 25 days. The litters of the rats in group B had a significantly higher mean weight than the rats in group A while the litters of the rats in group C had a significantly lower mean weight than the rats in groups B. It was concluded that intraperitoneally injected aqueous extract of alligator pepper, in the first trimester of pregnancy, can prevent the development of fetal macrosomia in Sprague-Dawley rats.

Selective control by posterior spinal nerve roots of micturition and erection in rats

The posterior rootlets in L6 and S1 spinal cord of adult male Sprague-Dawley rats underwent electrostimulation. The bladder pressure, urethral perfusion pressure and intracavernous pressure were recorded. When some posterior rootlets of L6 and Sl were electrostimulated, the intracavernous pressure peaked rapidly, but the bladder pressure and the urethral perfusion pressure curve did not show great change. When other rootlets were stimulated, the bladder pressure changed greatly, but the urethral perfusion pressure and the intracavernous pressure did not show great change. When different rootlets were stimulated, the urethral perfusion pressure changed maximally, but there were no great changes in bladder pressure or intracavernous pressure. Furthermore, stimulation of some rootlets produced simultaneous changes in two or three different pressure measures mentioned above. The results demonstrate that regulation by L6 and S1 posterior rootlets of the rat bladder detrusor, external urethral sphincter and penis cavernous body are significantly distinct. Different rootlets can be distinguished by electrostimulation.

Effects of Different Electromagnetic Fields on Circadian Rhythms of Some Haematochemical Parameters in Rats

Objective To investigate the effects of different electromagnetic fields on some haematochemical parameters of circadian rhythms in Sprague-Dawley rats. Methods The study was carried out in 18 male and 18 female rats in good health conditions exposed to 50 Hz magnetic sinusoid fields at the intensity of 1000 μT, 100 μT, and 0 μT （control group） respectively, and in 18 male and 18 female rats in good health conditions exposed to 1.8 GHz electromagnetic fields at the intensity of 50 V/m, 25 V/m and 0 V/m （control group）, respectively. Following haematochemical parameters for glucose, triglycerides, and total cholesterol were measured. Results Different effects of electromagnetic fields on circadian rhythms of both male and female rats were observed. Different changes occurred in some haematochemical parameters for glucose, triglycerides, and total cholesterol （P〈0.05）. Conclusion Exposure to different electromagnetic fields is responsible for the variations of some haematochemical parameters in rats.

萝卜硫素调节腺苷酸活化蛋白激酶/沉默信息调节器1/过氧化物酶体增殖活化受体γ辅助活化因子1α信号通路对妊娠高血压大鼠妊娠结局的影响

目的 探究萝卜硫素(SFN)通过调节腺苷酸活化蛋白激酶(AMPK)/沉默信息调节器1(SIRT1)/过氧化物酶体增殖活化受体γ辅助活化因子1α(PGC-1α)信号通路对妊娠期高血压疾病(HDP)大鼠妊娠结局的影响。方法 2021年3月至2022年6月,70只雌性大鼠受孕后分为对照组、HDP组、SFN-L组(SFN 5 mg/kg)、SFN-M(SFN 15 mg/kg)、SFN-H(SFN 30 mg/kg)、硫酸镁组(硫酸镁注射液100 mg/kg)、Compound C组(SFN 30 mg/kg+AMPK抑制剂Compound C 0.25 mg/kg),各组10只。在妊娠第13天起除对照组,其余各组妊娠大鼠尾静脉注射7 mg/kg L-NAME,连续注射4 d,建立HDP大鼠模型,对照组大鼠尾静脉注射0.9%氯化钠溶液。从造模成功后第1天(妊娠第17天)起,各给药组注射相应剂量的药物,对照组、HDP组注射0.9%氯化钠溶液,连续给药至妊娠第20天。检测妊娠第17天和第20天各组大鼠尾动脉压和24 h尿蛋白定量水平;试剂盒法检测大鼠血肌酐(SCr)和血尿素氮(BUN)水平;观察检测大鼠妊娠结局指标;HE染色观察胎盘组织和肾脏组织病理情况;蛋白质印迹法检测胎盘组织可溶性血管内皮生长因子受体-1(sFLT-1)、胎盘生长因子(PLGF)、内皮型一氧化氮合酶(eNOs)、磷酸化eNOs(peNOs)、磷酸化AMPK(p-AMPK)、AMPK、SIRT1、PGC-1ɑ蛋白水平。结果 HDP组大鼠血压[(152.52±4.79)mmHg比(101.63±4.15)mmHg]、24 h尿蛋白定量水平[(679.38±64.32)mg/L比(123.17±20.19)mg/L]、胎鼠病死率[(28.57±2.08)%比(0.96±0.11)%]、血清SCr和BUN水平、胎盘组织sFLT-1表达水平高于对照组(P<0.05),而胎鼠质量[(2.32±0.19)g比(4.75±0.43)g]、产仔数[(11.70±0.69)个比(7.10±0.57)个]、胎盘质量[(0.32±0.06)g比(0.58±0.12)g]、胎盘组织PLGF、p-eNOs、p-AMPK、SIRT1和PGC-1ɑ蛋白表达低于对照组(P<0.05),另外,HDP大鼠胎盘组织绒毛数量减少,胎盘结构缩小,部分绒毛显示纤维蛋白样坏死,肾脏组织内肾小球数目减少,结构异常;SFN-L组、SFN-M组、SFN-H组和硫酸镁组大鼠血压[(136.91±5.16)mmHg、(129.25±4.54)mmHg、(117.33±4.19)mmHg、(121.72±4.61)mmHg比(152.52±4.79)mmHg]、24 h尿蛋白定量水平[(595.91±53.05)mg/L、(532.23±49.76)mg/L、(461.16±35.15)mg/L、(482.74±39.58)mg/L比(679.38±64.32)mg/L]、胎鼠病死率、血清SCr和BUN水平、胎盘组织sFLT-1表达水平低于HDP组(P<0.05),胎鼠质量、产仔数、胎盘质量、胎盘组织PLGF、p-eNOs、p-AMPK、SIRT1和PGC-1ɑ蛋白表达高于HDP组(P<0.05),胎盘组织和肾脏组织结构异常程度减轻;AMPK抑制剂Compound C减弱了SFN对HDP大鼠血压、肾损伤和妊娠结局的保护作用。结论 SFN通过激活AMPK/SIRT1/PGC-1ɑ信号通路改善HDP大鼠妊娠结局。

CCl4诱导的肝纤维化大鼠模型肝小叶内卵圆细胞总体积与轮廓数密度变化的体视学分析

目的 定量研究CCl4诱导的肝纤维化大鼠肝小叶内卵圆细胞(HOC)总体积和轮廓数密度的变化。方法 将11只雄性健康SD大鼠随机分为对照组(n=5)、肝纤维化组(n=6),每周2次皮下注射CCl4与橄榄油混悬液,每次3 mL/kg。在肝纤维化造模5周后取材,从每只大鼠肝脏随机抽选5个大小约1 mm3的肝组织块分别制作1张Epon812环氧树脂包埋超薄切片,运用体视学方法结合透射电子显微镜技术,对大鼠肝小叶内的HOC总体积和轮廓数密度进行定量研究,另从每只大鼠剩余肝脏等距随机抽选4个2 mm厚的肝组织块并分别制作2张石蜡包埋的Masson染色切片,按照肝纤维化Metavir分期标准定性评估每只大鼠的肝纤维化程度。计量资料两组间比较采用成组t检验。结果 体视学定量研究显示,对照组肝小叶内HOC总体积为(15.40±7.63) mm3,肝纤维化组肝小叶内HOC总体积为(146.80±114.00) mm3,与对照组比较,肝纤维化组大鼠肝小叶内HOC总体积显著增加了8.53倍(t=-2.551,P=0.031);对照组肝小叶内HOC轮廓数密度为(56.20±40.40),肝纤维化组肝小叶内HOC轮廓数密度为(566.50±317.00),与对照组比较,肝纤维化组大鼠肝小叶内轮廓数密度显著增加了9.08倍(t=-3.539,P=0.006);定性观察研究结果显示,肝纤维化大鼠肝纤维化分期按照Metavir评分标准达到Ⅱ~Ⅲ期,大鼠窦周隙内肝星状细胞增生部位周围伴随着HOC的大量增生。结论 CCl4诱导肝纤维化大鼠肝小叶内HOC显著增生。