Effects of aerobic exercise time on cardiovascular and renal functions of 2K1C renal vascular hypertensive rats

AIM: To explore the impact of aerobic exercise (AE) time on mean arterial pressure (MAP), sinus bradycardia, heart and kidney histological changes and oxidative damage in the two-kidney and one-clip (2K1C) hypertensive rats, and to assess the specific effects of AE time on alleviation of hypertension. METHODS: Healthy male Wistar rats (n=60) were randomly divided into sham operation (sham) group and 2K1C group. After operation, the rats in these 2 groups were divided into sham sedentary (sham+SED) group, sham exercise (sham+AE) group, 2K1C se-dentary (2K1C+SED) group and 2K1C exercise (2K1C+AE) group. The rats in sham+AE group and 2K1C+AE group were subjected to AE for 10 weeks:swimming for 1 h/d. The MAP, sinus bradycardia and the histological changes of heart and kidney in these 4 groups were tested regularly. RESULTS: Compared with 2K1C+SED group, the rats in 2K1C+AE group had significantly improved MAP and sinus bradycardia at the 4th week, with reduced collagen deposition in the myocardium and kidney, decreased level of thiobarbituric acid reactive substances (TBARS) in the left ventricle and increased catalase (CAT) activity in the left ventricle and kidney. The results of the 6th to 10th weeks showed that the differences of MAP and sinus bradycardia between the rats in 2K1C+AE group and 2K1C+SED group had gradually narrowed. The TBARS levels in the left ventricle and kidney and CAT activity in both kidneys of the rats in 2K1C+AE group were partly restored at the 8th week. The collagen deposition in the heart and kidney of the rats in AE group was reduced to the lowest level at the 10th week. CONCLUSION: Short-time (about 4 weeks) AE effectively improves the MAP and sinus bradycardia of 2K1C renal vascular hypertensive rats and attenuates the damages of the heart and kidney by regulating oxidative stress, thus improving the cardiovascular and renal functions of 2K1C renal hypertensive rats.     

Effects of syringe material and temperature and duration of storage on the stability of equine arterial blood gas variables

OBJECTIVES: To evaluate the consistency of partial pressures (P) of arterial oxygen (aO(2)), arterial carbon dioxide (aCO(2)) and pH measurements in equine carotid arterial blood samples taken into syringes made from three different materials and stored at room temperature or placed in iced water for measurement at three different times. STUDY DESIGN: Prospective observational study over 19 days. ANIMALS: Four clinically normal Thoroughbred or Thoroughbred-cross horses (three geldings, one mare, mean age 6.25 years, range 5-7 years). METHODS: Identical blood samples were taken on two separate occasions from the carotid arteries of the four horses into syringes made of glass, plastic and polypropylene. PaO(2), PaCO(2) and pH determinations were performed on blood from each syringe type at 10, 60 and 120 minutes post-sampling with samples stored at room temperature (approximately 20 degrees C) or in iced water (approximately 0 degrees C). Data were analysed by anova and a split plot model fitting syringe within horse X pair and time within temperature within syringe. RESULTS: Syringe material, storage temperature and time before analysis all had significant effects on PaO(2) (p < 0.001). PaCO(2) was unaffected by syringe material or storage temperature. However, over 120 minutes, storage duration significantly (p = 0.002) affected values. Temperature of storage and duration prior to analysis both significantly affected pH values (p = 0.005 and p < 0.001, respectively), but syringe material did not. Several significant interactions between these variables were noted. CONCLUSIONS: Equine arterial blood gas determination has a different sensitivity to storage conditions compared to other veterinary species. CLINICAL RELEVANCE: For accurate equine arterial blood analysis, PaO(2) samples need to be analysed within 10 minutes or taken into glass syringes, stored on ice and analysed at 2 hours post-sampling. PaCO(2) and pH measurements can be performed on samples stored in glass, plastic or polypropylene syringes at room temperature for up to 1 hour post-sampling.     

利用X射线测定活体鹿茸骨化程度及其与生长速度的关系

为阐明鹿茸骨化与生长的关系,以5头雄性梅花鹿为试验材料,利用X射线测定活体鹿茸相对骨质密度（RBM）和鹿茸生长速度。结果表明：从脱盘到75d鹿茸生长速度递增并达高峰;75d以后生长速度下降,到120d基本停止生长;RBM在75d前增长缓慢,75d以后快速增长,并与鹿茸生长速度呈明显负相关（r=0.9）。     

Arteriosclerosis in the ventral aorta and epicarditis in the bulbus arteriosus of Atlantic salmon (Salmo salar L)

Spontaneous mortality of seemingly healthy, farmed Atlantic salmon (Salmo salar L) is an increasing problem in Norwegian aquaculture. In this study, we present a morphological study of the previously undescribed syndrome of arteriosclerosis of the ventral aorta and epicarditis of the adjacent bulbus arteriosus found in farmed Atlantic salmon, with wild‐captured fish as a control group. Both the ventral aorta and epicardium are vital for correct arterial compliance and vascular resistance in the respiratory capillaries of the gills. We discuss the possible implications of ventral aorta arteriosclerosis and epicarditis for blood vascular health and in particular for the increasing frequency of spontaneous gill bleeding in farmed salmon. As both these conditions primarily occur in farmed salmon, we suggest that they should be considered pathological.     

Effects of EGLN1 siRNA on growth of rat pulmonary artery smooth muscle cells under hypoxic condition

AIM: To observe whether EGLN1 gene is involved in the growth of pulmonary arterial smooth muscle cells (PASMCs) during hypoxia when EGLN1 gene expression was interference by siRNA. METHODS: The rat primary pulmonary arterial smooth muscle cells were cultured, and the specific lipidosome of EGLN1 siRNA was constructed and transfected into the PASMCs. The transfected PASMCs were cultured under hypoxia or normoxia conditions, respectively. The viability of the PASMCs was detected by CCK-8 assay. The protein expression of EGLN1 and vascular endothelial growth factor (VEGF) was determined by Western blot. RESULTS: The viability of the PASMCs was increased and the protein expression of VEGF was up-regulated in the PASMCs under hypoxic condition in a time-dependent manner. In hypoxia or normoxia condition, the viability and VEGF protein expression of the PASMCs were suppressed by EGLN1 siRNA. CONCLUSION: EGLN1 gene may involve in the growth of rat PASMCs by regulating VEGF protein level under hypoxic condition.     

环境低温和T3对肉鸡内皮素、一氧化氮和肺动脉压的影响

20 0只 AA肉鸡随机等分为对照组 (C)和试验组 (T) ,C组和 14日龄前 T组鸡按常规饲养。 T组自 14日龄起舍温从 2 5℃起每天降 1～ 2℃逐渐降至 12℃ ,同时在日粮中按 1.5 m g/ kg的剂量添加三碘甲腺原氨酸 (T3 )以诱发肺动脉高压综合征 (PHS)。分别于 2 1、2 8、35、42、49日龄测定 2组肉鸡平均肺动脉压 (m PAP)、红细胞压积 (PCV)、右心全心比 (RV/ TV)、血浆内皮素 (ET- 1)及一氧化氮 (NO)水平 ,同时记录 PHS发病率。结果显示 ,试验组肉鸡 m PAP升高 ,PHS发病率增加 ;PCV、RV/ TV及血浆 ET- 1水平与对照组相比都显著升高 (P<0 .0 1) ;m PAP变化与血浆 ET- 1含量变化之间存在显著正相关 ,2组间血浆 NO水平无显著差异 (P>0 .0 5 ) ,但都出现随日龄增加血浆 NO水平升高的现象。     

应用超高分辨率小动物超声系统研究高脂诱导的ApoE-/-小鼠动脉粥样硬化发生情况

以7~8周龄雄性SPF级ApoE^-/-小鼠为研究对象,高脂饲料喂养12周,按照不同喂养时间分为6组,喂养结束对小鼠进行血脂(TG、TC、HDL-C、LDL-C)检测和动脉超声影像学(动脉内中膜厚度、心脏左室收缩末期/舒张末期内径、左室校正质量、射血分数和缩短分数等指标)检测及动脉脂质沉积油红O染色观察,综合评价ApoE^-/-小鼠动脉粥样硬化模型的建立。结果显示,与对照相比较,Apo E^-/-小鼠心脏室间隔和左心室后壁增厚,左室质量增加,心脏功能降低。随着高脂饲料喂养周数的增加,ApoE^-/-小鼠血脂升高,升主动脉内膜厚度随之增加,从0.137 mm增加到0.195 mm;结合不同阶段ApoE^-/-小鼠动脉脂质沉积油红O染色结果,得出动脉脂质沉积不同程度的增加,与超声成像的结果保持一致。超高分辨率小动物超声系统在无创和活体情况下,监测ApoE^-/-小鼠的动脉粥样硬化的发生和发展,可作为小鼠模型建立的重要辅助工具。     

Finite element analysis of wall stress in the equine pulmonary artery

Reasons for performing study: Arterial calcification is found frequently in the pulmonary artery of racehorses, but the aetiology is unknown. Calcification might be associated with increased wall stress due to arterial geometry (shape) and exercise‐induced hypertension. Hypothesis: High wall stress levels are found in the regions associated with calcified lesion formation, exacerbated as transluminal pressure increases to levels associated with exercise. Methods: The pulmonary arteries of 5 horses, unaffected by calcification, were dissected and pressurised to resting and exercising physiological transluminal pressures and scanned with MRI. Arterial geometries were reconstructed to form 3D computer models and finite element analyses performed. Wall stress levels were measured in 4 regions of interest: the arterial trunk and bifurcation, the wall ipsilateral and contralateral to the bifurcation. Measurements were made for arterial transluminal pressures of 25, 50 and 100 mmHg. Results: High wall stress levels were consistently found at the pulmonary artery bifurcation and wall ipsilateral to the bifurcation, where calcified lesions typically form. Lower wall stress levels were found along the trunk and the wall contralateral to the bifurcation where lesions are less frequently found. Wall stress levels increased 5‐fold over a 4‐fold increase in pressure. The wall stress levels ranged 10 kPa in the wall of the branch contralateral to the bifurcation at 25 mmHg to 400 kPa in the bifurcation at 100 mmHg. Conclusions: Wall stress from arterial geometry and increased pulmonary artery transluminal pressure are factors that may be associated with calcification of the equine pulmonary artery. Potential relevance: Arterial calcification may increase the risk of arterial wall failure in racing horses.     

Validation of oscillometric blood pressure measurement using a Datex S/5 Compact multiparameter monitor in anaesthetized adult dogs

ObjectiveTo compare noninvasive (NIBP) with invasive blood pressure (IBP) measurements from a Datex S/5 Compact monitor in anaesthetized adult dogs, and to evaluate it according to the American College of Veterinary Internal Medicine (ACVIM) and the Association for the Advancement of Medical Instrumentation (AAMI) criteria.Study designProspective clinical study.AnimalsA group of 34 client-owned adult dogs.MethodsDogs were anaesthetized for different surgical procedures using different anaesthetic protocols. IBP was measured using a catheter placed in a dorsal pedal artery. A blood pressure cuff was placed over the contralateral dorsal pedal artery for NIBP measurement. Data were recorded using the Datex iCollect program, and paired readings were matched every 3 minutes for 60 minutes. Bland-Altman and error grid analyses were used to estimate the agreement between IBP and NIBP measurements, and its clinical significance, respectively. Data were reported as mean bias [lower, upper limits of agreement (LoA)].ResultsThe Datex S/5 monitor conformed to most ACVIM criteria. The correlation coefficient was less than 0.9 for systolic, diastolic, and mean arterial pressures (MAP). The best agreement between the noninvasive and invasive methods was observed for MAP, with LoA (–17 to 13 mmHg) and higher percentage of NIBP readings within 5 (55.6%), 10 (81.7%) and 20 (98.6%) mmHg of the IBP values. The Datex S/5 NIBP technology did not meet the AAMI validation criteria and less than 95% of the paired measurements were found within the green zone of the error grid analysis.Conclusions and clinical relevanceThe Datex S/5 monitor conformed to most ACVIM criteria but not with the more rigorous AAMI standards. Despite good agreement between IBP and NIBP for MAP measurements, care must be taken when using this device to guide therapeutic interventions of blood pressure in anaesthetized healthy adult dogs.