Effect of Kaiyu Qingwei Jianji on the morphometry and residual strain distribution of small intestine in experimental diabetic rats

AIM： To investigate the effect of a Chinese medicine, Kaiyu Qingwei Jianji （KYQWJJ） used for diabetic treatment, on the morphometry and residual strain distribution of the small intestine in streptozotocin （STZ） -induced diabetic rats. Correlation analysis was also performed between the opening angle and residual strain with the blood glucose level. METHODS： Forty-two male Wistar rats weighing 220-240 g were included in this study. Thirty-two STZ- induced diabetic rats were subdivided into four groups （n = 8 in each group）, i.e. diabetic control group （DM）; high dose of KYQWJJ （T1, 36g/kg per day）; low dose of KYQWJJ （T2, 17 g/kg per day） and Gliclazide （T3, 50 mg/kg per day）. Another ten rats were used as nondiabetic control （CON）. The medicines were poured directly into stomach lumen by gastric lavage twice daily. The rats of CON and DM groups were only poured the physiological saline. Blood glucose and plasma insulin levels were measured. Experimental period was 35 d. At the end of experiment, three 5-cm long segments were harvested from the duodenum, jejunum and ileum. Three rings of 1-2 mm in length for no-load and zero-stress state tests were cut from the middle of different segments. The morphometric data, such as the circumferential length, the wall thickness and the opening angle were measured from the digitized images of intestinal segments in the no-load state and zerostress state. The residual strain was computed from the morphometry data. Furthermore, the linear regression analysis was performed between blood glucose level with morphometric and biomechanical data in the different intestinal segments. RESULTS： The blood glucose level of DM group was consistent 4-fold to 5-fold higher than those in CON group during the experiment （16.89 ± 1.11 vs 3.44 ± 0.15 mmol/L, P 〈 0.001）. The blood glucose level in the T1 （16.89 ± 1.11 vs 11.08 ± 2.67 mmol/L, P 〈 0.01） and T3 groups （16.89 ± 1.11 vs 13.54 ± 1.73 mmol/L, P 〈 0.05）, but not in T2 group （P 〉 0.05） was significantly lower than those in DM group. The plasma insulin levels of DM, T1, T2 and T3 groups were significantly lower than those in CON group （10.98 ± 1.02, 12.52 ± 1.42,13.54 ± 1.56,10.96 ± 0.96 vs 17.84 ± 2.34 pmol/L respectively, P 〈 0.05）, but no significantly difference among the groups with exception of CON group. The wet weight/cm and total wall thickness of duodenum, jejunum and ileum in DM group were significantly higher than those in CON group （wet weight （g/cm）： duodenum 0.209 ± 0.012 vs 0.166 ± 0.010, jejunum 0.149 ± 0.008 vs 0.121 ± 0.004, ileum 0.134 ± 0.013 vs 0.112 ± 0.007; Wall thickness （mm）： duodenum 0.849 ± 0.027 vs 0.710 ± 0.026, jejunum 0.7259 ± 0.034 vs 0.627 ± 0.025, ileum 0.532 ± 0.023 vs 0.470 ± 0.010, all P 〈 0.05）, T1 and T3 treatment could partly restore change of wall thickness, but T2 could not. The opening angle and absolute value of inner and outer residual stain were significantly smaller in duodenal segment （188 ± 11 degrees, -0.31 ± 0.02 and 0.35 ± 0.03 vs 259 ± 15 degrees, -0.40 ± 0.02 and 0.43 ± 0.05） and larger in jejunal （215 ± 20 degrees, -0.30 ± 0.03 and 0.36 ± 0.06 vs 172 ± 19 degrees, -0.25 ± 0.02 and 0.27 ± 0.02） and ileal segments （183 ± 20 degrees, -0.28 ± 0.01 and 0.34 ± 0.05 vs 153 ± 14 degrees, -0.23 ± 0.03 and 0.29 ± 0.04） in DM group than in CON group （P 〈 0.01）. TI and T3 treatment could partly restore this biomechanical alteration, but strong effect was found in T1 treatment （duodenum 243 ± 14 degrees, -0.36 ± 0.02 and 0.42 ± 0.06, jejunum 180 ± 15 degrees, -0.26 ± 0.03 and 0.30 ± 0.06 and ileum 163 ± 17 degrees, -0.23 ± 0.03 and 0.30 ± 0.05, compared with DM, P 〈 0.05）. The linear association was found between the glucose level with most morphometric and biomechanical data. CONCLUSION： KYQWJJ （high dose） treatment could partly restore the changes of blood glucose level and the remodeling of morphometry and residual strain of small intestine in diabetic rats. The linear regression analysis demonstrated that the effect of KYQWJJ on intestinal opening angle and residual strain is partially through its effect on the blood glucose level.

Diet and Rat Strain as Factors in Nervous System Function and Influence of Confounders

The necessity for understanding normal human cognitive processes and behavior, and themechanisrns which result in dysfunction in these processes are dependant on utilization of a suitable animal model. In order to develop pharmaceutical agents to alleviate mental disturbances and enable the individual to cope within the norms of society, it is incumbent upon investigators to choose a species in which pharmacokinetic principles are established and resemble those of hurnans. The choice of rats in cognition research studies has specific advantages in that these anirnals possess similar pharrnacodynamic parameters to hurnans. Further advantages include availability, low cost, ease of breeding, maintenance and an extensive literature database which enable comparisons to present findings. However, there are substantial differences in the perforrnance of various rat strains in tasks of learning, memory, attention, and responses to stress or drugs. In addition to rat strain, quantity of thed also exerts profound consequences on animal behavior. The aim of this review is to demonstrate that there are differences in the central nervous systern responsivencess of rat strains to chemicals and these could be related to factors such as source of supplier, type and quantity of feed, or season of the year. It is also evident that the genotype differs amongst strains and this may be responsible for the observed differences in CNS sensitivity to chemicals. Strain differences must be identified and taken into consideration in interpretation of assessrnent of neurobehavioural functions. It is also incumbent upon the investigators to utilize healthy (diet-controlled) animal models.

Intravenous administration of glutathione protects parenchymal and non-parenchymal liver cells against reperfusion injury following rat liver transplantation

AIM:To investigate the effects of intravenous administration of the antioxidant glutathione (GSH) on reperfusion injury following liver transplantation. METHODS:Livers of male Lewis rats were transplanted after 24 h of hypothermic preservation in University of Wisconsin solution in a syngeneic setting.During a 2-h reperfusion period either saline (controls,n=8) or GSH (50 or 100 μmol/(h·kg),n=5 each) was continuously administered via the jugular vein. RESULTS:Two hours after starting reperfusion plasma ALT increased to 1 457±281 U/L (mean±SE) in controls but to only 908±187 U/L (P<0.05) in animals treated with 100 μmol GSH/(h·kg).No protection was conveyed by 50μmol GSH/(h·kg).Cytoprotection was confirmed by morphological findings on electron microscopy:GSH treatment prevented detachment of sinusoidal endothelial cells (SECs) as well as loss of microvilli and mitochondrial swelling of hepatocytes.Accordingly,postischemic bile flow increased 2-fold.Intravital fluorescence microscopy revealed a nearly complete restoration of sinusoidal blood flow and a significant reduction of leukocyte adherence to sinusoids and postsinusoidal venules.Following infusion of 50μmol and 100 μmol GSH/(h·kg),plasma GSH increased to 65±7 mol/L and 97±18 mol/L,but to only 20±3 mol/L in untreated recipients. Furthermore,plasma glutathione disulfide (GSSG) increased to 7.5±1.0 mol/L in animals treated with 100μmol/(h·kg) GSH but infusion of 50μmol GSH/(h·kg) did not raise levels of untreated controls (1.8±0.5 mol/L vs 2.2±0.2 mol/L). CONCLUSION:Plasma GSH levels above a critical level may act as a “sink” for ROS produced in the hepatic vasculature during reperfusion of liver grafts.Therefore,GSH can be considered a candidate antioxidant for the Drevention of reperfusion injury after liver transplantation,in particular since it has a low toxicity in humans.

Study on mitochondrial DNA diversity among 7 inbred strains of mice

Objective：To study the genetic variation of mitochondrial DNA （mtDNA） among common laboratory strains of inbred mice. Methods： The genetic polymorphism of mtDNA among 4 classical laboratory strains of inbred mice and 3 inbred strains of mice established in China was analyzed by polymerase chain reaction coupled with restriction fragment length polymorphism（PCR-RFLP） and PCR coupled with single-stranded conformation polymorphism（PCR-SSCP）. Results： With regard to the D-loop （Displacement loop, D-loop）, tRNA^ Met＋Glu＋Ile, and ND3 （NADH dehydrogenase subunit 3, ND3） gene fragments of mtDNA from these mice,no variation was revealed by PCR-RFLP at 46 restriction enzyme sites. Further analyzed by PCR-SSCP,the D-loop 5＇fragment and 3＇end fragment of mtDNA from these mice also showed no genetic variation. Conclusion： Owing to maternal mode of inheritance of mtDNA,the results indicate that these common inbred strains of mice share the same maternal lineage.

High IFN-α expression is associated with the induction of experimental autoimmune uveitis (EAU) in Fischer 344 rat

Th1-response plays a crucial role in determining pathogenesis of organ-specific autoimmune diseases. It is believed that both IL-12 and INF-alpha are initiators to regulate Th1-response. In our experimental autoimmune uveitis (EAU) model, both Lewis and Fischer 344 rats share the same MHC class II molecules, while Lewis rat is EAU susceptible and Fischer 344 rat is EAU resistant. However, under the same condition of immunization, if pertussis toxin (PTX) was injected intraperitoneally as an additional adjuvant, Fischer 344 rat can develop EAU. In this study we investigate which mechanisms are involved in the induction of EAU in CFA+R16+PTX-treated (CRP-treated) Fischer 344 rats. In vivo and in vitro data demonstrated that Th1-cytokine, IFN-gamma mRNA expression was significantly increased in disease target tissue-eyes and in draining lymph node cells of CRP-treated Fischer 344 rat. When IL-12 and IFN-alpha mRNA expression were compared in the experimental groups, only IFN-alpha mRNA expression was associated with EAU development. To distinguish the sources of IFN-alpha producing cells, it was observed that IFN-alpha expression was mainly produced by macrophages. It was further confirmed that normal macrophage from Fischer 344 rat was able to produce significant IFN-alpha in the presence of PTX. The data strongly suggested that IFN-alpha might be involved in initiating Th1-cell differentiation and in turn contribute to the induction of EAU. High IFN-alpha expression induced by PTX may represent a novel pathway to initiate Th1 response in Fischer 344 rat.

Regular nicotine intake increased tooth movement velocity,osteoclastogenesis and orthodontically induced dental root resorptions in a rat model

Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further （side） effects can be expected during orthodontic treatment at a nicotine exposure corresponding to that of an average European smoker. 63 male Fischer344 rats were randomized in three consecutive experiments of 21 animals each （A/B/C） to 3 experimental groups （7 rats, 112/3）. （A） cone-beam-computed tomography （CBCT）; （B） histology/serology; （C） reverse- transcription quantitative real-time polymerase chain reaction （RT-qPCR）/cotinine serology--（1） control; （2） orthodontic tooth movement （OTM） of the first and second upper left molar （NiTi closed coil spring, 0.25 N）; （3） OTM with 1.89 mg-kg- 1 per day s.c. of L（- ）-nicotine. After 14 days of OTM, serum cotinine and IL-6 concentration as well as orthodontically induced inflammatory root resorption （OIIRR）, osteoclast activity （histology）, orthodontic tooth movement velocity （CBCT, within 14 and 28 days of OTM） and relative gene expression of known inflammatory and osteoclast markers were quantified in the dental-periodontal tissue （RT-qPCR）. Animals exposed to nicotine showed significantly heightened serum cotinine and IL-6 levels corresponding to those of regular European smokers. Both the extent of root resorption, osteoclast activity, orthodontic tooth movement and gene expression of inflammatory and osteoclast markers were significantly increased compared to controls with and without OTM under the influence of nicotine. We conclude that apart from increased periodontal bone loss, a progression of dental root resorption and accelerated orthodontic tooth movement are to be anticipated during orthodontic therapy, if nicotine consumption is present. Thus patients should be informed about these risks and the necessity of nicotine abstinence during treatment.

Changes of phasic and tonic smooth muscle function of jejunum in type 2 diabetic Goto-Kakizaki rats

AIM:To generate phasic and tonic stress-strain curves for evaluation of intestinal smooth muscle function in type 2 diabetic rats during active and passive conditions.METHODS:Seven diabetic Goto-Kakizaki(GK)male rats,32-wk old(GK group),and 9 age-matched normal Wistar rats(Normal group)were included in the study.Jejunal segments were distended up to a pressure of10 cm H2O in an organ bath containing 37℃Krebs solution with addition of carbachol(CA).The pressure and outer diameter changes were synchronously recorded.Passive conditions were obtained using calcium-free Krebs solution containing ethylene glycol tetraacetic acid and papaverine.Total phasic,tonic and passive circumferential stress and strain were computed from the diameter and pressure data with reference to the zero-stress state geometry.The active phasic and tonic stresses were defined as the total phasic and tonic stresses minus the passive stress.RESULTS:Diabetes increased jejunal mucosa and muscle layer thicknesses compared to the Normal group(mucosa,755.8±63.3 vs 633.1±59.1μm,P<0.01;muscle,106.3±12.9 vs 85.2±11.7μm,P<0.05).The pressure and stress thresholds were decreased in the GK group after CA application compared to distensions without CA application(pressure,1.01±0.07vs 1.99±0.19 cmH2O,P<0.01;stress,0.11±0.01vs 0.24±0.02 kPa,P<0.01).CA application did not change the pressure and stress threshold in the Normal group(pressure,2.13±0.32 vs 2.34±0.32 cm H2O,P>0.05;stress,0.25±0.03 vs 0.35±0.06 kPa,P>0.05).The amplitude of total phasic,total tonic,active phasic and active tonic circumferential stresses did not differ for the distensions without CA application between the GK group and the Normal group.However,the total phasic and total tonic stresses increased after CA application in the GK group compared those in the Normal group.When normalized to muscle layer thickness,the amplitude of active stresses before CA application was lowest in the GK group compared with the Normal group.No difference was found during CA application.CONCLUSION:The stress generated by intestinal muscle normalized to the muscle layer thickness was lowest in GK rats compared to normal rats whereas the response to CA stimulation was preserved.

Integrative rodent models for assessing male reproductive toxicity of environmental endocrine active substances

In the present review, we first summarize the main benefits, limitations and pitfalls of conventional in vivo approaches to assessing male reproductive structures and functions in rodents in cases of endocrine active substance （EAS） exposure from the postulate that they may provide data that can be extrapolated to humans. Then, we briefly present some integrated approaches in rodents we have recently developed at the organism level. We particularly focus on the possible effects and modes of action （MOA） of these substances at low doses and in mixtures, real-life conditions and at the organ level, deciphering the precise effects and MOA on the fetal testis. It can be considered that the in vivo experimental EAS exposure of rodents remains the first choice for studies and is a necessary tool （together with the epidemiological approach） for understanding the reproductive effects and MOA of EASs, provided the pitfalls and limitations of the rodent models are known and considered. We also provide some evidence that classical rodent models may be refined for studying the multiple consequences of EAS exposure, not only on the reproductive axis but also on various hormonally regulated organs and tissues, among which several are implicated in the complex process of mammalian reproduction. Such models constitute an interesting way of approaching human exposure conditions. Finally, we show that organotypic culture models are powerful complementary tools, especially when focusing on the MOA. All these approaches have contributed in a combinatorial manner to a better understanding of the impact of EAS exposure on human reproduction.

Endothelin-1, an important mitogen of smooth muscle cells of spontaneously hypertensive rats

OBJECTIVE: To study the features of vascular smooth muscle cell (VSMC) proliferation induced by endothelin-1 (ET-1). METHODS: VSMCs of spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats were cultured and treated with ET-1. Basic fibroblast growth factor (bFGF) gene expression was measured using both Northern blot and an enzyme-linked immunoassay. RESULTS: ET-1 resulted in an increase in bFGF transcripts at 8 - 24 h; bFGF levels were significantly higher in VSMCs treated with ET-1 than in those not treated. However, VSMCs growth responses in SHR and WKY were different. Smooth muscle cells of SHR were hyper-responsive to ET-1. Maximal bFGF mRNA levels were elevated 3.5-fold at 4 h of stimulation in WKY and 8-fold at 8h in SHR4. Moreover, the proliferation of VSMCs induced by ET-1 was inhibited by antisense phosphorothioate oligodeoxynucleotides (10 micromol/L AS-bFGF) but not sense bFGF oligomers at the same concentrations, being reduced by 80% in SHR and 40% in WKY vs control, respectively. Furthermore, the effect of AS-bFGF oligomers on SHR SMC proliferation is significantly greater than on WKY SMC proliferation. CONCLUSION: ET-1 may be required for exaggerated vascular growth responses in SHR and bFGF may be involved.

Opening angles and residual strains in normal rat trachea

The no-load state and zero-stress state of the normal rat trachea were analyzed. It was found that there exist compressive residual strains in the inner wall region of the rat trachea and tensile residual strains in the outer wall region. The fact that the opening angle of the rat trachea cut at the cartilaginous region is significantly larger than that cut at the muscular portion shows that residual strains exist mainly in the muscular region in the rat trachea. It was also indicated that the opening angles and residual strains expressed by cutting at the muscular portion are basically identical along longitudinal location and those expressed by cutting in the cartilaginous region tend to increase in the longitudinal direction in the normal rat, and that there exists quantitatively positive correlation between the opening angles and residual strains in rat trachea. The results will help to further understand the opening angles and residual strains in the trachea and study tracheal remodeling in response to mechanical environment.

Influence of Valsartan on myocardial apoptosis in spontaneously hypertensive rats

OBJECTIVE: To explore the pathogenic changes of myocardial apoptosis in heart hypertrophy during hypertension and evaluate the anti-apoptosis effect of Valsartan. METHODS: Thirty spontaneously hypertensive rats (SHRs) were divided into two groups: 15 treated with Valsartan (20 mg x kg(-1) x d(-1)) (SHR + Valsartan group), the others with placebo (SHR + placebo group), with 15 normal Wistar rats as control. Systolic blood pressure was measured by the tail-cuff method. The observation period was from 8 to 16 weeks of age. Cardiac apoptosis was evaluated by a Terminal Deoxynucleotidyl Transferase-Mediated dUTP-biotin Nick End Labeling (TUNEL) assay. RESULTS: Mean blood pressure values were 127 +/- 2 mm Hg in controls, 163 +/- 6 mm Hg in the SHR + Valsartan group and 193 +/- 7 mm Hg in the SHR + placebo group at 16 weeks of age, whereas the blood pressure in 8-week-old SHR and Wistar rats were 175 +/- 3 mm Hg and 125 +/- 5 mm Hg, respectively. The ratio of the heart weight over body weight declined in Wistar (3.07 +/- 0.03 mg/g) and SHR + Valsartan groups (3.22 +/- 0.19 mg/g) compared with the SHR + placebo group (4.02 +/- 0.31 mg/g) (P

Endothelin receptor antagonist combined with a calcium channel blocker attenuates renal injury in spontaneous hypertensive rats with diabetes

OBJECTIVE: To investigate the effects of the mixed endothelin receptor antagonist, bosentan, combined with the long-acting calcium channel blocker, amlodipine, compared to the angiotensin-converting enzyme inhibitor, cilazapril, on the progressive renal injury in spontaneous hypertensive rats (SHR) with diabetes. METHODS: Diabetic hypertensive rats (SHR-DM) were induced by streptozotozin injected in male SHR (7-week-old),and divided into an untreated and three treated groups: 1) cilazapril treated group; 2) bosentan+amlodipine treated group; and 3) amlodipine treated group. Wistar Kyoto rats (WKY) and SHR rats served as normotensive and hypertensive control, respectively. The mean arterial blood pressure, renal function, endothelin and angiotensin II levels as well as the protein expression of renal extracellular matrix components and transforming growth factor (TGF)-beta1 were determined at the end of the 4th week. RESULTS: Mean arterial blood pressure significantly increased in SHR and SHR-DM rats compared to WKY rats. All the therapies reduced the blood pressure to normal levels. However, the enhanced urinary protein excretion, the decreased creatinine clearance as well as the increased plasma and intrarenal endothelin and angiotens in II levels were found in the untreated SHR-DM and prevented by treatment with bosentan+amlodipine and cilazapril. Similarly, these two kinds of therapies in SHR-DM abolished the overexpression of renal TGF-beta1 by Western blot analysis and reduced the accumulation of collagen type IV, laminin and fibronectin proteins by an immunochemical approach. Amlodipine monotherapy had no detectable effects on the above parameters. CONCLUSION: Bosentan combined with amlodipine can offer similar renoprotective effects on that of cilazapril and may be a potent therapy to attenuate renal injury by reducing renal protein levels of TGF-beta1 in diabetes with a hypertensive state.

Microsatellite Genotyping for Four Expected Inbred Mouse Strains from KM Mice

Chinese Kun Ming （KM） mouse, an outbreed strain of laboratory animal, has been widely utilized in related pharmaceutical and genetic studies throughout China. However, the value of KM mice to the research community has been severely limited, partially due to the fact that well-characterized inbred strain of KM mice is not available. Several expected inbred strains from KM mice have been bred, but their genetic purity remains uncertain. In this study, four expected inbred strains of KM mice （A1, T2, N2, and N4） were chosen and their inbred degree were compared with two classical inbred mouse lines （BALB/c and C57BL/6） by analyzing the genotypes of about 30 microsatellite markers. In the four strains, A1 and N4 were homozygous at all genotyped loci, but N2 and T2 were only heterozygous at locus D15Mit16. These results indicate that the level of genetic purity/homozygousity of A1, N4, N2, and T2 inbred line is comparable to those of BALB/c and C57BL/6. This study provided the first and solid evidence for genetic purity of four expected inbred strains of KM mice. These 4 inbred mice strains should be well maintained for further characterization and utilization in genetic studies.

Ventricular remodeling by Scutellarein treatment in spontaneously hypertensive rats

OBJECTIVE: To observe reversal of ventricular remodeling by the protein kinase C inhibitor Scutellarein in spontaneously hypertensive rats (SHRs). METHODS: Twelve SHRs were randomly divided into two groups. Scutellarein and saline (10 mg x kg(-1) x d(-1)) were given by intraperitoneal injection to two groups of rats separately. Systolic blood pressure (SBP) and ventricular weight index (LVW/BW, RVW/BW) were measured. A polarization microscope and an image analyzer system (IAS) were used to observe changes in cardiovascular structure and to count the content of cardiac muscle interstitial collagen. RESULTS: The pathologic changes in the left ventricle in the Scutellarein group rats (SHR(D)) improved to varying degrees, including hypertrophy of the cardiac muscle and collagen volume fraction. CONCLUSION: Scutellarein can reverse ventricular remodeling, improve myocardial stiffness and protect heart cardiac muscle.

Tong-xin-luo capsule inhibits left ventricular remodeling in spontaneously hypertensive rats by enhancing PPAR-γ expression and suppressing NF-κB activity

Background Tong-xin-luo capsule （TXL）, used as a traditional Chinese herb, offeres a therapeutic potential for treatment of cardiovascular diseases. It has been shown to exert a variety of pharmacological effects, including antihypertensive effects, and is able to improve ventricular remodeling. However, the mechanisms of its action are not completely understood. The aim of this study was to evaluate the molecular mechanisms of Tong-xin-luo capsule on left ventricular remodeling in spontaneously hypertensive rats （SHR）. Methods Sixteen eight-week-old SHRs were randomized into an SHR group （n=8） and a TXL group （n=8） that were given Tong-xin-luo capsule （1.5 mg·kg^-1·d^-1）. Eight Wistar Kyoto （WKY） rats fed with 0.9% NaCl served as the control group （WKY group）. Systolic blood pressure （BP）, body weight and heart rate were monitored once every two weeks. Ventricular remodeling was detected by histopathological examination. Nuclear factor kappa B P65 （NF-κB P65） and peroxisome proliferators activated receptor y （PPAR-γ） protein and phosphorylated inhibitor kappa a （IκBα） protein were detected by immunohistochemistry and western blot respectively. The physical interaction of the P65-P50 heterodimer with IκBα and NF-κB were measured by co-immunoprecipitation. PPAR-γ mRNA, collagen Ⅰ mRNA and collagen Ⅲ mHNA were measured by real-time PCR.Results TXL inhibited NF-κB P65 expression and ventricular remodeling and suppressed the activation of NF-κB compared with the SHR group （P〈0.01, P〈0.05）. TXL reduced IκBα phosphorylation, increased expression of PPAR-γ protein and enhanced the physical interaction of the P65-P50 heterodimer with IκBα. The mRNA expression of PPAR-γ was enhanced but the mRNA expression of collagen Ⅰ mRNA and collagen Ⅲ mRNA were suppressed by TXL. Conclusions In spontaneously hypertensive rats, TXL could inhibit ventricular remodeling induced by hypertension, and the inhibitory effect might be associated with the process of TXL increasing the expression of PPAR-γ that could result in the inhibition of the activation of NF-κB.

高频超声在构建SD大鼠皮下移植性乳腺癌模型中的应用

目的:应用MADB-106大鼠乳腺癌细胞悬液皮下移植法建立SD大鼠乳腺癌移植性肿瘤动物模型,并使用高频超声监测肿瘤生长情况。方法:选取7~8周龄雌性SD乳鼠16只,将处于对数生长期的MADB-106大鼠乳腺癌细胞悬液于大鼠腹股沟皮下接种,应用高频超声观察成瘤率、肿块大小、血供情况及其它声像图特征。结果:SD大鼠接种成功率为100%,死亡2只,剩余14只生长良好;超声检查肿块为类圆形,内部低回声且稍不均匀,边界尚清,后方回声衰减,彩色多普勒扫查肿块内部及周边可见较丰富血流信号;3周后切除瘤体组织,大体观肿块成灰白色,多呈椭圆形,部分边缘呈分叶状改变,肿瘤血管较丰富,镜下可见肿瘤细胞大小形状各异,核大深染,异型性明显。结论:通过MADB-106大鼠乳腺癌细胞接种于雌性SD大鼠腹股沟皮下,成功建立了大鼠乳腺癌移植性肿瘤动物模型。高频超声技术可以在SD大鼠乳腺癌皮下成瘤过程中对肿物的大小、形态、边界、内部回声及血流等生物学情况进行动态检测,是观察和评价瘤体动态变化过程的重要技术手段。

Five novel monoclonal antibodies to thymic epithelial cell surface antigens in rats

OBJECTIVE: To establish monoclonal antibodies (mAbs) against thymic epithelial cells and study the function of epithelial cells during T-cell differentiation in the thymus. METHODS: Hybridomas secreting mAbs against thymic epithelial cells were derived by immunization of Balb/c mice with two thymic epithelial cell lines, TaD3 and FTE. The distribution of antigens recognized by these mAbs was detected by immunochemical staining and cytofluorographic analysis, and the molecular weight of the antigens by immunoblotting. RESULTS: Five specific monoclonal antibodies (mAb) were obtained. On the basis of their distribution in the thymus determined by immunochemical staining, mAb RE-4D8 was regarded as clusters of thymic epithelium staining (CTES) type IIA: mAb RE-12B2, which showed a unique distribution pattern only in the medulla, was CTES type V: mAb RE-5C6 was CTES type IV: mAb RE-6D6 might be CTES type IIB: and mAb RE-1D4 was classified as type V. The molecular weight (MW) of antigen RE-4D8, RE-6D6 and RE-12B2 were 120 kDa, 220 kDa and 35 kDa, respectively. Antigen RE-1D4 is a novel marker of cortical epithelium, several established thymic epithelial cell lines were classified and their original intrathymic locations were determined by these mAbs. Thymic cell lines, TuD3 and FTE were cortical phenotypes whereas TaD3 had a medullar phenotype. CONCLUSIONS: These mAbs clearly demonstrate the heterogeneity of the thymic epithelium; they could detect antigens not only in the cytoplasm but also on the surface of thymic epithelial cells. Our data suggest that these newly established mAbs may help elucidate the interaction between thymocytes and epithelial cells during T cell maturation.

Genetic Quality Analysis of Xiphophorus helleri RR-B Strain Using 18 Microsatellite Loci

[Objective] The study aimed to further understand the genetic quality of Xiphophorus helleri RR-B strain and estimate the feasibility of microsatellite markers in genetic monitoring of aquatic laboratory animals.[Method] Eighteen microsatellite loci which had polymorphism in wild X. helleri were used for genetic quality analysis of RR-B strain (red eyes and red body) by PCR. [Result] All these 18 microsatellite loci displayed single allelic gene band in 30 individuals of X. helleri RR-B strain and the average homozygote rate reached 100%. [Conclusion] These loci could be used as markers in genetic monitoring of X. helleri RR-B strain, which had obtained fairly high genetic homozygosity by inbreeding for more than 20 generations. This study provided basic data for establishing the molecular genetic monitoring standard of aquatic laboratory animals.

PVG大鼠生化标记基因的测定

目的 对PVG大鼠进行生化标记基因的测定。方法 依据国家标准GB/T 14927.1—2008《实验动物近交系小鼠、大鼠生化标记检测法》测定,随机抽取4只PVG大鼠,取(肺、肾、小肠、睾丸)组织器官进行样品制备,用醋酸纤维薄膜电泳法检测11个生化位点(Hbb、Cs1、Alp1、Akp1、Esl、Es3、Es4、Es6、Es8、Es9和Esl0)。结果 PVG大鼠11个位点的基因型分别是Hbb为b型,Cs1为b型,Alp1为b型,Akp1为a型,Esl为a型,Es3为d型,Es4为b型,Es6为b型,Es8为b型,Es9为a型和Esl0为a型,且均为纯合。结论 PVG大鼠遗传生化标记结果符合近交系特征。

Effects of electroacupuncture at Taichong(LR 3) and Baihui(DU 20)on cardiac hypertrophy in rats with spontaneous hypertension

OBJECTIVE: To investigate the effects of electroacupuncture(EA) at Taichong(LR 3) and Baihui(DU 20)on myocardial hypertrophy in spontaneously hypertensive rats(SHRs).METHODS: Thirty-six SHRs were randomly assigned to model, EA, and Losartan groups, with twelve rats per group. Twelve Wistar Kyoto rats were selected as the normal control group. Systolic blood pressure(SBP) and cardiac function were measured in all rats.Expression levels of factors associated with the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/Akt/mTOR) pathway were evaluated by Western blotting and real-time PCR.Pathological changes of the heart tissue were observed by hematoxylin-eosin staining.RESULTS: After treatment, enhanced SBP was significantly decreased in the EA and Losartan groups compared with the model group(P < 0.01). Echocardiographic and morphological analyses revealed that enhanced end-diastolic interventricular septal thickness and left ventricular posterior wall thickness, as well as ratio of left ventricular weight to body weight were markedly diminished in the EA and Losartan groups(P < 0.01 or P < 0.05), while reduced left ventricular end-diastolic dimension and left ventricular ejection fraction were significantly ameliorated(P < 0.01). Real-time PCR and western blotting analyses showed that the expression levels of PI3K,Akt, and mT OR in SHRs were significantly up-regulated by EA and Losartan(P < 0.01), while the expression levels of PTEN and ANP were down-regulated(P < 0.01).CONCLUSION: EA at Taichong(LR 3) and Baihui(DU20) inhibited the development of cardiac hypertrophy and improved the cardiac function in SHRs, possibly through regulation of the PI3K/Akt/mTOR signalling pathway.