Upregulation of TRPC1/6 may be involved in arterial remodeling in rat.

BACKGROUND: Hypertension and its complications are associated with arterial remodeling. Transient receptor potential cationic channels (TRPCs) are important nonselective cationic channels that regulate calcium homeostasis in mammalian cell membranes. We aimed to study the expression of various TRPC isoforms in spontaneously hypertensive rat (SHR) carotid arterial remodeling and explore the relationship between SHR carotid arterial remodeling and TRPC expression. MATERIALS AND METHODS: Thirty male SHRs were randomly divided into three groups and sacrificed at ages 4, 8, and 18 wk, respectively, with matching control male Wistar-Kyoto rats (n = 10). Caudal artery systolic blood pressure (SBP) was measured every 2 wk. Carotid artery remodeling parameters including carotid artery wall thickness (MT), lumen diameter (LD), medial area, collagen area rate, and average nuclear area in media cells were determined after histologic staining. Real-time polymerase chain reaction and immunoblot assays were performed to assess TRPC expression. Carotid artery remodeling and TRPC expression were reevaluated after ginsenoside Rb1 treatment from eighth to eighteenth week. RESULTS: Carotid artery remodeling of SHRs was aggravated gradually with age and SBP, as well as MT, LD, MT/LD, medial area, average nuclear area in media cells, and collagen deposition, most obvious at 18 wk. Interestingly, expression of TRPC1, 3, and 6 increased with age and SBP, with TRPC1/6 showing significant differences between the Wistar-Kyoto and 18 wk groups; TRPC4/5 expression was unchanged and TRPC7 was barely detected. Importantly, after ginsenoside Rb1 treatment, TRPC1/6 expressions were significantly inhibited, SBP decreased, and the carotid artery remodeling in SHRs relieved. CONCLUSIONS: Upregulation of TRPC1 and TRPC6 may be involved in carotid arterial remodeling in SHRs.

[The value of aggressive diuretic therapy in acute decompensated stage of chronic heart failure].

OBJECTIVE: To evaluate both the efficacy, safety, length of stay in hospital and expenses of aggressive diuretic therapy in patients with acute decompensation of chronic heart failure (CHF). METHODS: The retrospective analysis was conducted in the patients with acute decompensation CHF New York Heart Association (NYHA) class III or IV in department of cardiology of Fujian Medical University Union Hospital from January 1st 2006 to September 1st 2007. The 24-hour urine volume on the 2nd day was equivalent or over 2 400 ml was defined as aggressive diuretic therapy group, and those with less than 2 400 ml of urine as non-aggressive diuretic therapy group. The biochemical parameters and vital signs were compared before and after aggressive diuretic therapy, and the mortality, the length of stay and expenses were also compared between the two groups. RESULTS: One hundred and ninety-five patients were enrolled in the study, there were 73 and 122 patients in aggressive diuretic therapy group and in non-aggressive diuretic therapy group respectively. The mortality in aggressive diuretic therapy group was lower than that in non-aggressive diuretic therapy group (1.4% vs. 9.8%, P<0.05). The length of stay, total expenses and average cost in aggressive diuretic therapy group were lower than those in non-aggressive diuretic therapy group respectively [the length of stay: 11 days vs. 16 days; total expenses: 8 483 yuan vs. 12 182 yuan; average expenseI: 721.1 yuan/d vs. 854.4 yuan/d; average expenseII (except for examination expenses): 580.0 yuan/d vs. 698.2 yuan/d, P<0.05 or P<0.01]. There were no significant changes in biochemical parameters and heart rate before and after aggressive diuretic therapy. The systolic pressure (SBP) and diastolic pressure (DBP) were reduced significantly after aggressive diuretic therapy [SBP: (118.2±16.9) mm Hg vs. (127.0±24.9) mm Hg; DBP: (67.2±4.5) mm Hg vs. (75.2±4.9) mm Hg, 1 mm Hg=0.133 kPa, P<0.05 and P<0.01]. No hypotension symptoms such as dizziness and chest distress were found in all patients. CONCLUSION: Aggressive diuretic therapy in patients with acute decompensation CHF is a safe, effective mode of therapy. It can reduce the length of stay in hospital, expenses and the mortality during hospitalization.

Mechanical Property Tests and Strength Formulas of Basalt Fiber Reinforced Recycled Aggregate Concrete.

In order to investigate the influence of basalt fibers (BFs) on the mechanical performance of recycled aggregate concrete (RAC), some groups of RAC specimens were first tested involving different types of fibers such as carbon fibers, steel fibers, polypropylene fibers and hybrid fibers. The main four indices for the investigation consisted of cube compressive strengths, axial compressive strengths, splitting tensile strengths and Young's modulus. The effects of fiber volume fractions on the RAC slumps were also discussed. Meanwhile, the mechanical properties and failure modes of the BF-reinforced RAC were compared with those of other fiber-reinforced RAC and common concrete (CC). Subsequently the optimal volume fractions of BFs were explored for different mechanical properties within the volume fraction range of 0⁻0.2%. The back propagation neural networks were further applied to predict and validate the optimal BF fractions. Lastly, the general strength formulas, as well as the elastic modulus formula, for BF-reinforced RAC were deducted based on the specimen test results. It is found that the addition of fibers may improve the failure modes of RAC and different fibers present positive or negative effects on the mechanical properties. The optimal volume fractions of BF with respect to the four mechanical indices are 0.1%, 0.15%, 0.1% and 0.2% respectively. The proposed strength and elastic modulus formulas of BF-reinforced RAC provide satisfactory predictions with the test results and thus can be used as a reference in practice.

[Effect of shexiang baoxin pill in alleviating myocardial fibrosis in spontaneous hypertensive rats].

OBJECTIVE: To investigate the effects and mechanisms of Shexiang Baoxin Pill (SBP) on myocardial fibrosis in spontaneous hypertensive rats (SHR). METHODS: SHR of 12 weeks old were divided into the SBP group, the control group (treated with benazepril) and the model control group. The effects on such indexes as systolic blood pressure (SBP), left ventricular mass (LVM), left ventricular mass index (LVMI), content of myocardial collagen (MC) in left ventricle, extracellular matrix fibronectin (FN), laminin (LN), cardiac fibroblast (cFb) and transforming growth factor-beta1 (TGF-beta1) were determined after 12 weeks of treatment. RESULTS: SBP had no marked pressure depressive effect, but had the effect similar to that of benazepril in reducing the level of LVM, LVMI and content of MC (P < 0.05), as well as the content of LN, FN in myocardium, cFb count and TGF-beta1 expression (P < 0.05). CONCLUSION: SBP can prevent and treat myocardial fibrosis, whose action is independent of its hypotensive effect. The mechanism may be associated with such factors as the decrease of MC synthesis in left ventricle and the deposition of extracellular matrix.

Effects of exercise of different intensities on the angiogenesis, infarct healing, and function of the left ventricle in postmyocardial infarction rats.

BACKGROUND: Lifestyle interventions, including physical exercise, are feasible options for the prevention and treatment of cardiovascular diseases. In this study, the effects of exercise of different intensities on the infarct region, function, and angiogenesis of the left ventricle (LV) in postmyocardial infarction (MI) rats were investigated and the levels of vascular endothelial growth factor (VEGF) proteins in the LV and plasma were examined. MATERIALS AND METHODS: Male Sprague-Dawley rats were randomly assigned to six groups. The exercise-trained rats observed a daily 60-min treadmill routine 5 days/weeks for 6 weeks. Different treadmill speeds were used in the high-intensity exercise (HIE), moderate-intensity exercise (MIE), and low-intensity exercise (LIE) groups, whereas the untrained rats remained sedentary (Sed). At 6 weeks, all rats underwent either an acute MI operation or a sham (Sh) MI operation 24 h after their last treadmill exercise or the corresponding Sed protocol. They were then killed 7 days after recovery. Echocardiographic and hemodynamic measurements were taken at the end of the experimental protocol. The infarct regions were analyzed using Masson's trichrome staining, whereas intramyocardial microvessels were detected using Factor VIII-related antigen staining. The cardiac VEGF protein levels were determined by western blotting analysis, and plasma VEGF concentrations were examined by enzyme-linked immunosorbent assay. RESULTS: Compared with the corresponding parameters in the Sed-Sh group, LV function did not significantly ameliorate and microvessel density did not increase in the MIE-Sh group. Compared with the Sed-MI group, the MIE-MI and HIE-MI groups had significantly reduced LV infarct size, improved hemodynamic parameters, and increased fractional shortening, scar thickness, and microvessel density, these parameters did not significantly change in the LIE-MI group. In addition, the MIE-MI and HIE-MI rats had significant differences in hemodynamic parameters and microvessel density. Compared with those of the Sed-MI group, the heart and plasma of the exercise-trained rats in the MIE-MI and HIE-MI groups displayed higher levels of VEGF protein, but the difference between the MIE-MI and HIE-MI groups was not significant. CONCLUSIONS: Moderate-intensity running before acute MI improved LV function, reduced scar size, and increased scar thickness and microvessel density in post-MI rats. Exercise at a higher intensity could have further small effects. LIE may be beneficial, but it would not be sufficient to improve MI. Moderate-intensity and high-intensity running upregulated the expression of VEGF protein and increased microvessels, which may have partly improved cardiac function after MI in this study.