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Hypertension is an important risk factor for cardiovascular and cerebrovascular diseases,which can damage structure and function of vital organs such as the heart,brain and kidney.Pseudo hypertension (PHT) refers to the blood pressure measured by ordinary cuffmanometry is higher than that of the arterial puncture,which is an essential factor of refractory hypertension.Recent findings have suggested that the elderly patients with concomitant history of atherosclerotic disease,renal insufficiency,and diabetes mellitus have the highest risk of pseudohypertension.The incidence rate ofpseudohypertension is about 1.7％-50％ in domestic and international studies.In the clinical treatment,the misdiagnosis of hypertension of patients with excessive blood pressure will lead to severe perfusion defects.In this review,we will focus on the diagnosis and pathogenesis of pseudohypertension.
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<p><b>BACKGROUND</b>Erythropoietin (EPO) and granulocyte colony-stimulating factor (G-CSF) are both potential novel therapeutics for use after myocardial infarction (MI). However, their underlying mechanisms remain unclear and the efficacy of monotherapy with EPO or G-CSF is also controversial. Therefore, we investigated the effects of combined treatment with EPO and G-CSF on neovascularization and cardiac function in post-infarction rats and explored the potential mechanisms.</p><p><b>METHODS</b>Four groups of rats were used: control (saline injection after MI, i.h.), EPO (a single dose of 5 000 IU/kg after MI, i.h.), G-CSF (a dose of 50 µg× kg(-1)× d(-1) for 5 days after MI, i.h.), and both EPO and G-CSF (EPO+G-CSF, using the same regiment as above). Cardiac function was assessed by echocardiography before and 1 day, 7 days, 14 days and 21 days after MI. CD34(+)/Flk-1(+) cells in the peripheral blood were evaluated by flow cytometry before and 3 days, 5 days and 7 days after MI. The infarct area and angiogenesis in the peri-infarct area were analyzed. The mRNA and protein expression of vascular endothelial growth factor (VEGF) and stromal-derived factor-1a (SDF-1α) in the peri-infarct area were detected by real-time quantitative RT-PCR and Western blotting.</p><p><b>RESULTS</b>Compared with the control and monotherapy groups, the EPO+G-CSF group had significantly increased CD34(+)/Flk-1(+) endothelial progenitor cells (EPCs) in the peripheral blood (P < 0.05), up-regulated VEGF and SDF-1α levels in the peri-infarct region (P < 0.05), enhanced capillary density (P < 0.05), reduced infarct size (P < 0.05) and improved cardiac structure and function (P < 0.05). G-CSF alone did not dramatically increase EPCs in the peripheral blood, enhance capillary density in the peri-infarct area or reduce infarct size compared with the control group.</p><p><b>CONCLUSIONS</b>Combined treatment with EPO and G-CSF increased EPCs mobilization, up-regulated VEGF and SDF-1α levels in the post-infarction microenvironment, subsequently enhanced neovascularization in the peri-infarct region and reduced infarct size. All factors contributed to its beneficial effects on cardiac function in post-infarction rats.</p>
Subject(s)
Animals , Male , Rats , Blotting, Western , Chemokine CXCL12 , Metabolism , Echocardiography , Erythropoietin , Therapeutic Uses , Flow Cytometry , Granulocyte Colony-Stimulating Factor , Therapeutic Uses , Myocardial Infarction , Drug Therapy , Metabolism , Neovascularization, Physiologic , Rats, Sprague-DawleyABSTRACT
Objective To explore the effects of the β3 adrenergic receptor (β3-AR) agonist BRL37344 on cardiac fibroblast proliferation and collagen fiber hyperplasia in Wistar rats by promoting the phosphaticlylinositol 3 kinase-protein kinase B(PI3K-Akt) signal transduction pathway. Method Cardiac fibroblasts(CFbs) were isolated from 1 - 3 day-old Wistar rats under the sterile environment in the laboratory of the First Affiliated Hospital of Hasbin Medical University, by using enzyme digestion and an modified technique of differential anchoring velocity.The cultured myocardial cells were randomly (random number) divided into five groups. ① In blank group, rats were not treated with drug; ②in BRL group, rats were treated with BRL37344; ③in LY group, rats were treated with LY294002(PI3K antagonist) for one hour before treated with BRL37344;④in Akt-Ⅰ group,rats were treated with Akt-Ⅰ (Akt antagonist) for one hour before treated with BRL37344;⑤in L-A group, rats were treated with LY294002 and Akt-Ⅰ for one hour before treated with BRL37344. MTT colorimetric method and RT-PCR were used to observe the role of β3-AR agonist with or without PI3K antagonist and/or Akt antagonist in cardiac fibroblast proliferation (CFP) and collagen fiber hyperplasia (CFH). Comparisons between groups were made by one-way ANOVA and Tukey test. Results ①β3-AR was present in the CFbs. ②Compared with BRL group, the CFP and CFH in LY and Akt-Ⅰ groups were lower (P ＜0.01) and those in L-A group were lowest (P ＜ 0.01). ③Compared with blank group,the expressions of type Ⅰ and type Ⅲ fiber mRNA obliviously increased in BRL group (P ＜ 0.01),and at 48 hours,the expressionrs reached peak. At 48 hours,compared with BRL group,the expressions in LY and Akt-Ⅰ groups were lower, and were lowest in L-A group ( P ＜0.01). Conclusions BRL37344 promotes cardiac fibroblast proliferation and expressions of type Ⅰ and Ⅲ collagen fiber mRNA by activating the PI3K-Akt signal transduction pathway.
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AIM To observe whether acute stimulation of BRL 37344, a β3-adrenergic receptor (β3-AR) agonist, has the same effects of exacerbating hemodynamics and increasing in β3-AR expression on rats with failing heart as chronic administration. METHODSRats received two doses of isoprenaline (Iso, 340 mg·kg-1, sc, with a 24-h interval) to prepare heart failure model. After 8 weeks, rats were given iv BRL 37344 0.4 nmol·kg-1·min-1 for 10 min. Hemodynamics were measured at 0, 10, 30 min, 1, 2, 3 h, 1, 2 and 7 d after BRL 37344. Levels of β-AR mRNA in myocardium were measured at 0, 1, 2 and 7 d after BRL 37344 by reverse transcription-polymerase chain reaction. RESULTSCompared with Iso group, heart rate, left ventricular end systolic pressure and +dp/dtmax were significantly higher, and left ventricular end diastolic pressure was significantly lower during 1-3 h after BRL 37344 injection in Iso+BRL group. Then, they were restored to the same level as that prior to BRL 37344 injection. Compared with normal control, the levels of β1-, β2- and β3-AR mRNA displayed no significant change in BRL group;the level of β1-AR mRNA was lower and the level of β3-AR mRNA was higher in Iso group. In Iso+BRL group, much more lower β1-AR mRNA level and much higher β3-AR mRNA level were shown on d 2 and d 7 than Iso group. CONCLUSION Acute administration of β3-AR agonist has a shorter improved hemodynamics. But it caused the same result as chronic administration in reduction of β1-AR mRNA and increment of β3-AR mRNA in failure hearts, which may aggravate the cardiac functions.
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Objective:Autoimmune mechanisms, including cellular and humoral immune, are likely to participate in the pathogenesis of at least a subgroup of idiopathic dilated cardiomyopathy(IDC), in which cellular immune-mediated one plays a more important role. Cytotoxic T lymphocyte associated antigen-4(CTLA-4) is the major negative regulatory factor of cellular immunity. This study was conducted to investigate the association of CTLA-4 gene promoter -318C/T polymorphism, exon 1 A/G polymorphism and 3′ untranslated region microsatellite polymorphism with susceptibility to IDC in Han Chinese.Methods:Polymerase chain reaction-restriction fragment length polymorphisms(PCR-RFLP) techniques were used to analyze the polymorphisms of CTLA-4 promoter -318, exon 1 A/G and 3′ untranslated region in the unrelated Han ethnic population in Heilongjiang Province(including 72 IDC patients and 100 normal controls). Serum sCTLA-4 was tested by ELISA. The relationship of CTLA-4 genotype and alleles frequencies with sCTLA-4 was evaluated by linear regression analysis.Results:Compared with controls, the frequencies of GG genotype(0.604 2 and 0.739 6, P=0.012) and the G allele(0.360 0 and 0.560 0, P=0.008) were significantly increased in patients with IDC. Increased serum sCTLA-4 was found in the IDC group compared with the controls[(1.87?1.06)?g/L vs (0.54?0.19)?g/L, P