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Background: Hyperuricemia may predispose to renal damage, but in end-stage renal disease lower uric acid concentrations have been associated with higher mortality. In experimental studies, uric acid has promoted renal fibrosis and inflammation, but some studies have shown nephroprotective effects probably due to alleviated oxidative stress. We studied the influence of moderate hyperuricemia on kidney morphology in 5/6 nephrectomized rats.Methods: Three weeks after subtotal nephrectomy or sham-operation, rats were put on 2.0% oxonic acid (uricase inhibitor) diet for 9 weeks. Blood pressure was monitored using tail-cuff. At close of the study, blood, urine, and kidney samples were taken, and renal histology, mast cell count, and oxidative stress markers were determined. Kidney tissue inflammation and fibrosis were evaluated using RT‑PCR and immunohistochemistry.Results: Oxonic acid diet increased plasma uric acid levels by >80 µmol/l without influencing blood pressure. Creatinine clearance was reduced by ~60% in both remnant kidney groups, and by ~30% in hyperuricemic sham-operated rats. In remnant kidney rats with suppressed plasma renin activity, moderate hyperuricemia decreased glomerulosclerosis, tubulointerstitial damage, and kidney mast cell count, but did not influence the fibrosis marker collagen I mRNA content. In both hyperuricemic groups, the mast-cell product 11-epi-prostaglandin-F2α excretion to the urine and kidney tissue COX‑2 levels were decreased.Conclusions: Hyperuricemic remnant kidney rats displayed improved kidney morphology and reduced markers of oxidative stress and inflammation. Thus, moderately increased plasma uric acid had beneficial effects on the kidney in this low-renin model of experimental chronic renal insufficiency.

Hyperactive poly(ADP-ribose) polymerases (PARP) promote ischemic heart failure (IHF) after myocardial infarction (MI). However, the role of tankyrases (TNKSs), members of the PARP family, in pathogenesis of IHF remains unknown. We investigated the expression and activation of TNKSs in myocardium of IHF patients and MI rats. We explored the cardioprotective effect of TNKS inhibition in an isoproterenol-induced zebrafish HF model. In IHF patients, we observed elevated TNKS2 and DICER and concomitant upregulation of miR-34a-5p and miR-21-5p in non-infarcted myocardium. In a rat MI model, we found augmented TNKS2 and DICER in the border and infarct areas at the early stage of post-MI. We also observed consistently increased TNKS1 in the border and infarct areas and destabilized AXIN in the infarct area from 4 weeks onward, which in turn triggered Wnt/β-catenin signaling. In an isoproterenol-induced HF zebrafish model, inhibition of TNKS activity with XAV939, a TNKSs-specific inhibitor, protected against ventricular dilatation and cardiac dysfunction and abrogated overactivation of Wnt/β-catenin signaling and dysregulation of miR-34a-5p induced by isoproterenol. Our study unravels a potential role of TNKSs in the pathogenesis of IHF by regulating Wnt/β-catenin signaling and possibly modulating miRNAs and highlights the pharmacotherapeutic potential of TNKS inhibition for prevention of IHF.

ObjectivesImpaired protein kinase signaling is a hallmark of ischemic heart disease (IHD). Inadequate understanding of the pathological mechanisms limits the development of therapeutic approaches. We aimed to identify the key cardiac kinases and signaling pathways in patients with IHD with an effort to discover potential therapeutic strategies.MethodsCardiac kinase activity in IHD left ventricle (LV) and the related signaling pathways were investigated by kinomics, transcriptomics, proteomics, and integrated multi-omics approach.ResultsProtein kinase A (PKA) and protein kinase G (PKG) ranked on top in the activity shift among the cardiac kinases. In the IHD LVs, PKA activity decreased markedly compared with that of controls (62% reduction, p = 0.0034), whereas PKG activity remained stable, although the amount of PKG protein increased remarkably (65%, p = 0.003). mRNA levels of adenylate cyclases (ADCY 1, 3, 5, 9) and cAMP-hydrolysing phosphodiesterases (PDE4A, PDE4D) decreased significantly, although no statistically significant alterations were observed in that of PKGs (PRKG1 and PRKG2) and guanylate cyclases (GUCYs). The gene expression of natriuretic peptide CNP decreased remarkably, whereas those of BNP, ANP, and neprilysin increased significantly in the IHD LVs. Proteomics analysis revealed a significant reduction in protein levels of “Energy metabolism” and “Muscle contraction” in the patients. Multi-omics integration highlighted intracellular signaling by second messengers as the top enriched Reactome pathway.ConclusionThe deficiency in cAMP/PKA signaling pathway is strongly implicated in the pathogenesis of IHD. Natriuretic peptide CNP could be a potential therapeutic target for the modulation of cGMP/PKG signaling.

Current literature suggests a higher risk of pregnancy-related complications in patients with renal fibromuscular dysplasia (FMD). The aim of our study was to assess the nature and prevalence of pregnancy-related complications in patients subsequently diagnosed with FMD. A call for participation was sent to centers contributing to the European/International FMD Registry. Patients with at least 1 pregnancy were included. Data on pregnancy were collected through medical files and FMD characteristics through the European/International FMD Registry. Data from 534 pregnancies were obtained in 237 patients. Despite the fact that, in 96% of cases, FMD was not diagnosed before pregnancy, 40% of women (n=93) experienced pregnancy-related complications, mostly gestational hypertension (25%) and preterm birth (20%), while preeclampsia was reported in only 7.5%. Only 1 patient experienced arterial dissection and another patient an aneurysm rupture. When compared with patients without pregnancy-related complications, patients with complicated pregnancies were younger at FMD diagnosis (43 versus 51 years old; P P =0.003) but underwent more often renal revascularization (63% versus 40%, P

Cardiogenic shock (CS) is a life-threatening emergency. New biomarkers are needed in order to detect patients at greater risk of adverse outcome. Our aim was to assess the characteristics of miR-21-5p, miR-122-5p, and miR-320a-3p in CS and evaluate the value of their expression levels in risk prediction. Circulating levels of miR-21-5p, miR-122-5p, and miR-320a-3p were measured from serial plasma samples of 179 patients during the first 5–10 days after detection of CS, derived from the CardShock study. Acute coronary syndrome was the most common cause (80%) of CS. Baseline (0 h) levels of miR-21-5p, miR-122-5p, and miR-320a-3p were all significantly elevated in nonsurvivors compared to survivors (p &lt, 0.05 for all). Above median levels at 0h of each miRNA were each significantly associated with higher lactate and alanine aminotransferase levels and decreased glomerular filtration rates. After adjusting the multivariate regression analysis with established CS risk factors, miR-21-5p and miR-320a-3p levels above median at 0 h were independently associated with 90-day all-cause mortality (adjusted hazard ratio 1.8 (95% confidence interval 1.1–3.0), p = 0.018, adjusted hazard ratio 1.9 (95% confidence interval 1.2–3.2), p = 0.009, respectively). In conclusion, circulating plasma levels of miR-21-5p, miR-122-5p, and miR-320a-3p at baseline were all elevated in nonsurvivors of CS and associated with markers of hypoperfusion. Above median levels of miR-21-5p and miR-320a-3p at baseline appear to independently predict 90-day all-cause mortality. This indicates the potential of miRNAs as biomarkers for risk assessment in cardiogenic shock.

Preeclampsia is a vascular pregnancy disorder that often involves impaired placental development. HO-1 (heme oxygenase 1, encoded by HMOX1 ) is a stress response enzyme crucial for endothelial and placental function. Long version of the guanine–thymine (GT n ) microsatellite in the HMOX1 promoter decreases HO-1 expression, and the long maternal repeat is associated with late-onset preeclampsia. Our aim was to study whether the length of fetal repeat is associated with mother’s preeclampsia, whether the length of fetal and maternal repeats affect HO-1 levels in placenta and maternal serum, and whether HO-1 levels are altered in preeclampsia. We genotyped the repeat in the cord blood of 609 preeclamptic and 745 nonpreeclamptic neonates. HO-1 levels were measured in 36 placental samples, and in the first (222 cases/243 controls) and third (176 cases/53 controls) pregnancy trimester serum samples using enzyme-linked immunosorbent assay. The long fetal GT n repeat was associated with preeclampsia and its severe and early-onset subtypes. Interaction analysis suggested the maternal and fetal effects to be independent. Placental or serum HO-1 levels were not altered in preeclamptics, possibly reflecting heterogeneity of preeclampsia. Carriers of the long fetal and maternal repeats had lower placental and serum HO-1 levels, respectively, providing functional evidence for the association. We conclude that the long fetal GT n repeat may increase mother’s risk for especially severe and early-onset preeclampsia. The fetal and maternal risk alleles likely predispose to different disease subtypes.

Carbon monoxide (CO), produced by heme oxygenase-1 (HO-1), is an endogenous paracrine factor involved in the regulation of cardiovascular structure and function. We studied the effects of a synthetic CO releasing molecule (CORM-3) on cardiac recovery and myocardial microRNA expression after myocardial infarction (MI). Male Wistar rats with MI (n = 75) or sham-operated controls (n = 75) were treated from day 4 to day 14 after MI either with synthetic CORM-3 or with inactive iCORM and killed 2, 4 or 8 weeks post-MI. Infarct size, vascular and capillary densities, the amount of cardiomyocytes in the infarct area, and cardiomyocyte proliferation and apoptosis were determined. PCR was used for microRNA and mRNA quantification, western blotting to evaluate protein expression and echocardiography to assess cardiac structure and function. CORM-3 treatment increased vascular density (P0.05 vs. iCORM) and the proportion of cardiomyocytes (P0.05 vs. iCORM) in the infarct area. Ejection fraction improved (P0.05) and left ventricular volumes decreased (P0.05) in CORM-3 treated MI groups compared to iCORM treatment. CORM-3 treatment decreased the amount of proliferating Ki67 positive cardiomyocytes in the infarct/border area at week 2 after MI compared to iCORM treatment, whereas the amount of apoptotic cardiomyocytes did not differ between CORM-3 and iCORM groups. Compared to iCORM treatment, CORM-3 decreased expression on miR-206 in the remote area at week 2 after MI. The CO releasing molecule CORM-3 improved structural and functional cardiac recovery after MI. Modulation of HO-1-CO axis may prove novel drug targets to facilitate cardiac recovery after myocardial injury.

Sodium glucose cotransporter 2 (SGLT2) inhibitors reduce HbA1c, blood pressure, and weight in patients with type 2 diabetes. To investigate the effect of renal function on reductions in these parameters with the SGLT2 inhibitor empagliflozin, we assessed subgroups by baseline estimated glomerular filtration rate (eGFR; Modification of Diet in Renal Disease) in pooled data from five 24-week trials of 2286 patients with type 2 diabetes randomized to empagliflozin or placebo. Reductions in HbA1c with empagliflozin versus placebo significantly diminished with decreasing baseline eGFR. Reductions in systolic blood pressure (SBP) with empagliflozin were maintained in patients with lower eGFR. The mean placebo-corrected changes from baseline in systolic blood pressure at week 24 with empagliflozin were -3.2 (95% confidence interval -4.9,-1.5) mmHg, -4.0 (-5.4, -2.6) mmHg, -5.5 (-7.6, -3.4) mmHg, and -6.6 (-11.4, -1.8) mmHg in patients with an eGFR of 90 or more, 60 to 89, 30 to 59, and under 30 ml/min/1.73m(2), respectively. Similar trends were observed for diastolic blood pressure. Weight loss with empagliflozin versus placebo tended to be attenuated in patients with a lower eGFR. Results were consistent in a 12-week ambulatory blood pressure monitoring trial in 823 patients with type 2 diabetes and hypertension. Thus, unlike HbA1c reductions, systolic blood pressure and weight reductions with empagliflozin are generally preserved in patients with chronic kidney disease.

In the EMPA-REG BP trial, empagliflozin significantly reduced systolic and diastolic blood pressure (SBP and DBP) compared with placebo at week 12 in patients with type 2 diabetes mellitus (T2DM) and hypertension. In a post-hoc analysis, we assessed the effect of empagliflozin on SBP and DBP using 24-hour ambulatory BP monitoring in patients categorized as dippers (sleep-time mean SBP ≤ 90% of awake-time mean; n = 417) or non-dippers (sleep-time mean SBP > 90% of awake-time mean; n = 350). In dippers, adjusted mean (SE) changes from baseline in mean 24-hour SBP (mm Hg) at week 12 were -0.2 (0.7) with placebo vs -3.8 (0.6) and -3.9 (0.7) with empagliflozin 10 and 25 mg, respectively (both P

Objectives: Elderly patients undergoing vascular surgery are at major risk for perioperative cardiac complications. The authors investigated continuous electrocardiographic Holter monitoring in a postoperative setting to determine the degree of postoperative ischemic load and its possible associations with perioperative myocardial infarction. Design: A prospective, observational study. Setting: One university hospital. Participants: The study comprised 51 patients aged 65 years or older undergoing peripheral arterial surgery. Interventions: Continuous electrocardiographic monitoring with a Holier device was started postoperatively and continued for 72 hours or until discharge. Postural changes were recorded using a 3-axis accelerometer. Standard 12-lead electrocardiography, high-sensitive troponin T measurements, and an inquiry of ischemic symptoms were performed 4 times perioperatively. Measurements and Main Results: The primary outcomes were ischemic load (area under the function of ischemic ST-segment deviation and ischemic time) and perioperative myocardial infarction. During 3,262.7 patient-hours of monitoring, 17 patients (33.3%) experienced 608 transient ischemic events, all denoted by ST-segment depression. Of these 17 patients, 5 experienced perioperative myocardial infarction. The mean ischemic load in all patients was 913.2 +/- 2,797.3 mu V x minute. Ischemic load predicted perioperative myocardial infarction, with an area under receiver operating characteristics curve (95% confidence interval) of 0.87 (0.75-0.99). Ischemic changes occurred most frequently during hours 24 to 60 of monitoring. Ischemia was asymptomatic in 14 of 17 patients (82.4%). Conclusion: Postoperative myocardial ischemia was common in peripheral vascular surgery patients and may progress to perioperative myocardial infarction. Ischemic load was a good predictor of perioperative myocardial infarction. Ambulatory electrocardiographic monitoring solutions for continuous postoperative ischemia detection are warranted in the surgical ward. (C) 2017 Elsevier Inc. All rights reserved.

Myofibrils made up of actin, myosin, and associated proteins generate the contractile force in muscle, and, consequently, mutations in these proteins may lead to heart failure. Septins are a conserved family of small GTPases that associate with actin filaments, microtubules, and cellular membranes. Despite the importance of septins in cytoskeleton organization, their role in cardiomyocyte organization and function is poorly characterized. Here, we show that septin 7 is expressed in both embryonic and adult zebrafish hearts and elucidate the physiological significance of sept7b, the zebrafish ortholog of human septin 7, in the heart in embryonic and larval zebrafish. Knockdown of sept7b reduced F-actin and α-cardiac actin expression in the heart and caused disorganization of actin filaments. Electron microscopy of sept7b-depleted larvae showed disorganization of heart myofibrils and partial detachment from Z-disks. Functional studies revealed that knockdown of sept7b leads to reduced ventricular dimensions, contractility, and cardiac output. Furthermore, we found that depletion of sept7b diminished the expression of retinaldehyde dehydrogenase 2, which catalyzes the synthesis of retinoic acid necessary for heart morphogenesis. We further observed that the sept7b and retinoic acid signaling pathways converge to regulate cardiac function. Together, these results specify an essential role for sept7b in the contractile function of the heart.NEW & NOTEWORTHY Knockdown of the zebrafish ortholog of human septin 7 ( sept7b) destabilizes cardiac actin and reduces ventricular dimensions, contractility, and cardiac output in larval zebrafish, indicating that sept7b is essential for cardiac function. We further found that sept7b and retinoic acid signaling pathways converge to regulate cardiac function. These data prompt further studies defining the role of sept7b in cardiomyopathies.

The prevalence of diabetes around the world has reached epidemic proportions and is projected to increase to 642 million people by 2040. Diabetes is already the leading cause of end-stage kidney disease (ESKD) in most developed countries, and the growth in the number of people with ESKD around the world parallels the increase in diabetes. The presence of kidney disease is associated with a markedly elevated risk of cardiovascular disease and death in people with diabetes. Several new therapies and novel investigational agents targeting chronic kidney disease patients with diabetes are now under development. This conference was convened to assess our current state of knowledge regarding optimal glycemic control, current antidiabetic agents and their safety, and new therapies being developed to improve kidney function and cardiovascular outcomes for this vulnerable population.

The let-7c family of micro-RNAs (miRNAs) is expressed during embryonic development and plays an important role in cell differentiation. We have investigated the role of let-7c in heart regeneration after injury in adult zebrafish. let-7c antagomir or scramble injections were given at one day after cryoinjury (1 dpi). Tissue samples were collected at 7 dpi, 14 dpi and 28 dpi and cardiac function was assessed before cryoinjury, 1 dpi, 7 dpi, 14 dpi and 28 dpi. Inhibition of let-7c increased the rate of fibrinolysis, increased the number of proliferating cell nuclear antigen (PCNA) positive cardiomyocytes at 7 dpi and increased the expression of the epicardial marker raldh2 at 7 dpi. Additionally, cardiac function measured with echocardiography recovered slightly more rapidly after inhibition of let-7c. These results reveal a beneficial role of let-7c inhibition in adult zebrafish heart regeneration.

The majority of patients with type 2 diabetes mellitus (T2DM) have hypertension requiring combination therapy. Sodium glucose cotransporter 2 (SGLT2) inhibitors are novel glucose-lowering drugs with shared and potentially unique beneficial effects on cardiovascular risk beyond glycemic control. This review focuses on the potential role of SGLT2 inhibitors in the treatment of hypertension associated with T2DM.SGLT2 inhibitors reduce office SBP by 3-5 mmHg and DBP by 2-3 mmHg across all class members. Corresponding clinically meaningful, significant blood pressure (BP) lowering effects have been confirmed using 24 h ambulatory BP monitoring. SGLT2 inhibitors reduce BP irrespective of the type of background antihypertensive medication. The antihypertensive actions of SGLT2 inhibitors involve several mechanisms including modest diuretic effects, weight loss, and direct vascular effects leading to decreased arterial stiffness and vascular resistance. The first-in class cardiovascular outcome trial with empagliflozin showed a significant reduction in a composite endpoint of cardiovascular death, nonfatal stroke, and nonfatal myocardial infarction in T2DM patients at high risk for cardiovascular events.SGLT2 inhibitors have clinically significant antihypertensive effects. SGLT2 inhibition could be a potentially useful supplement to the BP-lowering treatment armamentarium in patients with T2DM.

OBJECTIVE To investigate the efficacy, safety, and tolerability of empagliflozin in patients with type 2 diabetes and hypertension. RESEARCH DESIGN AND METHODS Patients (N = 825) with type 2 diabetes and hypertension (mean seated systolic blood pressure [SBP] 130–159 mmHg and diastolic blood pressure [DBP] 80–99 mmHg) were randomized (double blind) to 10 mg or 25 mg empagliflozin or placebo once daily for 12 weeks. RESULTS At week 12, adjusted mean difference versus placebo in change from baseline in mean 24-h SBP (ambulatory blood pressure monitoring [ABPM]) was −3.44 mmHg (95% CI −4.78, −2.09) with 10 mg empagliflozin and −4.16 mmHg (−5.50, −2.83) with 25 mg empagliflozin (both P < 0.001). At week 12, adjusted mean difference versus placebo in change from baseline in mean 24-h DBP (ABPM) was −1.36 mmHg (95% CI −2.15, −0.56) with 10 mg empagliflozin and −1.72 mmHg (95% CI −2.51, −0.93) with 25 mg empagliflozin (both P < 0.001). Changes in office BP were consistent with ABPM. Adjusted mean difference versus placebo in change from baseline in HbA1c at week 12 was −0.62% (95% CI −0.72, −0.52) (−6.8 mmol/mol [95% CI −7.9, −5.7]) with 10 mg empagliflozin and −0.65% (95% CI −0.75, −0.55) (−7.1 mmol/mol [95% CI −8.2, −6.0]) with 25 mg empagliflozin (both P < 0.001). Empagliflozin was well tolerated. One patient on placebo and one patient on 10 mg empagliflozin reported events consistent with volume depletion. CONCLUSIONS Empagliflozin was associated with significant and clinically meaningful reductions in BP and HbA1c versus placebo and was well tolerated in patients with type 2 diabetes and hypertension.

The let-7c family of micro-RNAs (miRNAs) is expressed during embryonic development and plays an important role in cell differentiation. We have investigated the role of let-7c in heart regeneration after injury in adult zebrafish. let-7c antagomir or scramble injections were given at one day after cryoinjury (1 dpi). Tissue samples were collected at 7 dpi, 14 dpi and 28 dpi and cardiac function was assessed before cryoinjury, 1 dpi, 7 dpi, 14 dpi and 28 dpi. Inhibition of let-7c increased the rate of fibrinolysis, increased the number of proliferating cell nuclear antigen (PCNA) positive cardiomyocytes at 7 dpi and increased the expression of the epicardial marker raldh2 at 7 dpi. Additionally, cardiac function measured with echocardiography recovered slightly more rapidly after inhibition of let-7c. These results reveal a beneficial role of let-7c inhibition in adult zebrafish heart regeneration.

Introduction: We studied the effects of angiotensin type 1 receptor blockade (ARB) on formation of new cardiomyocytes, neovascularization and ventricular remodelling after myocardial infarction (MI). Methods: Male Wistar rats with MI or sham-operated controls were treated with either losartan or vehicle. Bromodeoxyuridine (BrdU) was given to identify newly formed cardiac cells. Immunohistochemical analysis was used to quantify proliferative and apoptotic cardiomyocytes, vascular structures and c-Kit+ stem/progenitor cells, western blot- ting to evaluate gene expression, and planimetry and echocardiography to assess cardiac structure and function. Results: The number of BrdU+ cardiomyocytes increased similarly in the vehicle and losartan treated MI groups. The number of apoptotic or proliferating cardiomyocytes did not differ between losartan and vehicle treated rats. Losartan induced an increase in capillary and BrdU+ vascular densities in the infarct border zone. Losartan treatment completely prevented post-MI cardiac hypertrophy. In the non-infarcted myocardium the amount of all BrdU+ cells (including non- cardiomyocyte cells) was highest in the vehicle treated MI rats at week 4. Conclusions: The number of newly formed cardiomyocytes increased after MI. Angiotensin II blockade neither stimulated nor prevented cardiomyocyte regeneration. ARB treatment increased vascular densities in the infarct border zone and modulated remodelling of the non-infarcted myocardium preventing effectively post-MI cardiac hypertrophy.

Cell sheet-based tissue engineering shows great potential in the treatment of ischaemic heart disease. However, treatment efficacy is compromised by low blood and nutrient supply. The aim of this study was to investigate the effect of pro-angiogenic vascular endothelial growth factor (VEGF)-modified mesenchymal stem cell (MSC) sheet transplantation therapy in ischaemic heart failure. Rat MSCs were manipulated to overexpress the VEGF gene. In vitro, the antiapoptotic and paracrine effects were assessed under hypoxic conditions. In vivo, we evaluated the therapeutic effect of VEGF-modified MSC sheet therapy in a rat model of acute myocardial infarction (AMI). Forty-five Wistar rats were divided into three groups; one group underwent AMI (control), another underwent AMI and WT sheet transplantation (WT-MSC) and a third group underwent AMI and VEGF sheet transplantation (VEGF-MSC). Echocardiography was performed after 3, 10 and 28 days. Samples for histological analysis were collected at the end of the study. The VEGF gene protected MSCs against apoptosis. In vitro, VEGF overexpression significantly reduced MSC apoptosis compared with wild-type and enhanced VEGF secretion under hypoxic conditions. Capillary density in the infarct border zone was higher in VEGF-MSC-transplanted animals than in WT-MSC-treated animals. Furthermore, VEGF-MSC-transplanted animals had a smaller infarct size than WT-MSC-treated animals and exhibited remarkable functional recovery. These findings support the premise that transplantation of proangiogenic gene-modified MSCs may be valuable for mediating substantial functional recovery after AMI. Copyright © 2012 John Wiley & Sons, Ltd.

The calcium sensitizer levosimendan has shown beneficial effects on cardiac remodelling in spontaneously diabetic Goto-Kakizaki (GK) rats 12 weeks after experimental myocardial infarction (MI). However, the short-term effects and the cellular mechanisms remain partially unresolved. The aim was to study the effects of oral levosimendan treatment on the myocardial gene expression profile in diabetic GK rats 4 weeks after MI/sham operation. MI was induced to diabetic GK rats. Twenty-four hours after surgery, rats were randomized into four groups: MI, MI +levosimendan (1 mg/kg/day), sham-operated and sham-operated +levosimendan. Cardiac function and histology were examined 1, 4 and 12 weeks after MI. The effects of levosimendan on cardiac gene expression profile were investigated by microarray analysis. Levosimendan ameliorated post-infarct heart failure and cardiac remodelling. Levosimendan altered the expression of 264 of MI and sham rats, respectively; these changes were associated with alterations in two Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Levosimendan up-regulated 3 genes in the renin-angiotensin system pathway [angiotensin receptor 1 (Agtr1), chymase 1 (Cma1) and thimet oligopeptidase 1 (Thop1)] and down-regulated 3 genes in the glycerolipid metabolism pathway [diacylglycerol kinase gamma (Dgkg), carboxyl ester lipase (Cel) and Diacylglycerol kinase iota]. Levosimendan induced opposite effects on the gene expression of pleckstrin homology (PH) domain containing family f (Plekhf1), carboxymethylenebutenolidase homologue (Cmbl) (up-regulation) and hydroxyprostaglandin dehydrogenase 15 (Hpgd) (down-regulation) as compared with MI. MI versus sham affected 420 genes and was associated with alterations in 12 KEGG pathways. The beneficial effects of levosimendan on cardiac hypertrophy in sham-operated GK rats was associated with altered expression in 522 genes and associated with three KEGG pathways including purine metabolism, cell cycle pathway and pathways in cancer. Levosimendan protects against post-infarct heart failure and cardiac remodelling. Analysis of the cardiac transcriptome revealed several genes that are regulated by levosimendan. These genes may represent novel drug targets for heart failure and diabetic cardiomyopathy.

Myoblast transplantation therapy for chronic heart failure (HF) is impaired by early donor cell death and reduced graft viability. Although epicardial implantation of cell sheets can prevent the initial loss of transplanted cells, limited vascularization subjects the sheets to apoptotic stress. We studied the efficacy of antiapoptotic bcl2 in myoblast sheet therapy for rat chronic HF. Myocardial infarction was induced by left anterior descending coronary artery ligation and HF was allowed to develop for 4 weeks. Thereafter, wild type (L6-WT; n=16) or Bcl-2-expressing (L6-Bcl2; n=19) myoblast sheets were transplanted epicardially. Control rats (n=21) underwent left anterior descending coronary artery ligation and re-thoracotomy. Five rats were sham-operated in both surgeries. Four weeks after transplantation, only the L6-Bcl2 rats showed improved left ventricular ejection fraction. Their vascular density in the damaged myocardium was greater, and they had more proliferating cells. The L6-Bcl2 group had an increased amount of myocytes in the infarct area. Soluble factors from L6-Bcl2 sheets induced a 2.9-fold increase in endothelial cell proliferation, and enhanced endothelial wound healing as compared to the L6-WT sheets. These effects were inhibited by SU5416 and were thus dependent on Flt1/Flk1 signaling. In conclusion, bcl2 improves efficacy of myoblast sheet transplantation and promotes proangiogenic paracrine signaling.

Heme oxygenase-1 (HO-1), a known cytoprotective enzyme implicated also in the cell cycle regulation and angiogenesis, exerts many of its beneficial effects through carbon monoxide (CO). We studied the roles of HO-1 and CO in cardiac regeneration after myocardial infarction. Prior to coronary artery ligation, male Wistar rats were given either cobolt protoporphyrin IX to induce HO-1 or CO-donor methylene chloride. Cardiac regeneration was assessed by immunohistochemistry and confocal microscopy. CO significantly increased the accumulation of c-kit+ stem/progenitor cells into the infarct area and induced formation of new coronary arteries by promoting a substantial differentiation of c-kit+ cells into vascular smooth muscle cells (c-kit+/GATA6+ cells). Furthermore, CO increased proliferation of cardiomyocytes in the infarct border area at 4weeks post-infarction. This suggests proliferation of newly formed cardiomyocytes derived from c-kit+ cells as 10% of c-kit+ cells expressed early cardiac marker Nkx2.5. Increased expression of hypoxia-inducible factor-1alpha (HIF-1alpha), stromal cell derived factor-1alpha (SDF-1alpha) and vascular endothelial growth factor-B (VEGF-B) were found in the infarct areas of CO-donor pretreated hearts suggesting that these factors potentially promoted the migration of c-kit+ cells into the infarct area and subsequent vasculogenesis and myocardial regeneration by CO. HO-1 increased both capillary and vascular densities, while only a small increase of c-kit+ cells was found. HO-1 upregulated SDF-1alpha, but did not have effect on HIF-1alpha and VEGF-B. In conclusion, HO-1 and CO have differential roles and mechanisms of action in cardiac regeneration. Modulation of the HO-1/CO axis may provide a novel tool for the repair of cardiac injury.

Background Diabetes increases the risk for fatal myocardial infarction and development of heart failure. Levosimendan, an inodilator acting both via calcium sensitization and opening of ATP-dependent potassium channels, is used intravenously for acute decompensated heart failure. The long-term effects of oral levosimendan on postinfarct heart failure are largely unknown. Objective To examine whether oral treatment with levosimendan could improve cardiac functions and prevent cardiac remodeling after myocardial infarction in a rodent model of type 2 diabetes, the Goto-Kakizaki rat. Methods Myocardial infarction (MI) was induced to diabetic Goto-Kakizaki and nondiabetic Wistar rats by coronary ligation. Twenty-four hours after surgery, Goto-Kakizaki and Wistar rats were randomized into four groups: MI group without treatment, MI group with levosimendan for 12 weeks (1 mg/kg per day), sham-operated group, sham-operated group with levosimendan. Blood pressure, cardiac functions as wells as markers of cardiac remodeling were determined. Results In Goto-Kakizaki rats, MI induced systolic heart failure, pronounced cardiac hypertrophy in the remote area, and sustained cardiomyocyte apoptosis. Postinfarct cardiac remodeling was associated with increased atrial natriuretic peptide, interleukin-6 and connective tissue growth factor mRNA expressions, as well as three-fold increased cardiomyocyte senescence, measured as cardiac p16 INK4a mRNA expression. Levosimendan improved cardiac function and prevented postinfarct cardiomyocyte hypertrophy, cardiomyocyte apoptosis, and cellular senescence. Levosimendan also ameliorated MI-induced atrial natriuretic peptide, IL-6, and connective tissue growth factor overexpression as well as MI-induced disturbances in calcium-handling proteins (SERCA2, Na + -Ca 2+ exchanger) without changes in diabetic status or systemic blood pressure. In nondiabetic Wistar rats, MI induced systolic heart failure; however, the postinfarct cardiac remodeling was associated with less pronounced cardiac hypertrophy, cardiomyocyte apoptosis, inflammatory reaction, and induction of cellular senescence. Levosimendan only partially prevented postinfarct heart failure and cardiac remodeling in Wistar rats. Conclusion Our findings suggest a therapeutic role for oral levosimendan in prevention of postinfarct heart failure and cardiac remodeling in type 2 diabetes and underscore the importance of sustained cardiomyocyte apoptosis and induction of cellular senescence in the pathogenesis.

We describe a new principle for measuring concentrations of pharmacologically active captopril or other angiotensin-converting enzyme (ACE) inhibitors in blood. Serum is incubated with 125-I-labeled ACE inhibitor (substance 351A, a lisinopril analogue, Merck Sharp & Dohme) in a nonequilibrated system, in which label and ACE inhibitor compete for binding to added serum ACE. Free label is separated by adsorption to coated charcoal. Concentration of captopril or other ACE inhibitor is calculated from a standard curve. Results in healthy volunteers showed rapid absorption of captopril with maximal concentration of active drug within 1 h, and fast disappearance within 2.5 h. Stability of captopril was improved by immediate 1:100 dilution of blood samples with assay buffer. In spite of this precaution, analysis should be performed within two days to avoid loss of active drug due to polymerization and protein binding. Samples of other tested ACE inhibitors can be frozen and later analyzed at convenience. The new principle is simple, sensitive, and specific.

ObjectivesRenal insufficiency is a risk factor for poor outcome after infrainguinal bypass in patients with critical limb ischemia (CLI). Estimated glomerular filtration rate (eGFR) takes age, gender and body size into account and therefore represents actual renal function more accurately than serum creatinine level alone. The aim of this study was to determine the impact of different stages of renal insufficiency on outcome and to assess the prognostic significance of eGFR in patients with CLI.Material and methods603 patients with CLI who underwent infrainguinal bypass between January 2002 and December 2005 at our institution were included in this retrospective study. We estimated GFR using the Modification of Diet in Renal Disease (MDRD) Study equation. Survival, leg salvage and amputation-free survival were calculated using Kaplan–Meier method. Cox regression analysis was performed to calculate hazard ratios for different outcome variables.ResultsAdjusted hazard ratio (HR) of mortality, limb loss and limb loss and/or death for eGFR 200μmol/l was 4.0 (95% CI 2.22–7.39) vs 3.5 (95% CI 1.82–6.84), 6.5 (95% CI 2.71–15.59) vs 6.2 (95% CI 2.47–15.56) and 4.0 (95% CI 2.40–6.63) vs 3.6 (95% CI 2.03–6.25), respectively.ConclusionEstimated GFR is better predictor of survival, leg salvage and amputation-free survival than serum creatinine alone. eGFR

Cardiovascular complications are a major problem in chronic renal failure. We examined the effects of plasma calcium, phosphate, parathyroid hormone (PTH), and calcitriol on cardiac morphology in 5/6 nephrectomized rats. Fifteen weeks after nephrectomy rats were given a control diet, high-calcium or -phosphorus diet, or given paricalcitol treatment for 12 weeks. Sham-operated rats were on a control diet. Blood pressure, plasma phosphate, and PTH were increased, while the creatinine clearance was reduced in remnant kidney rats. Phosphate and PTH were further elevated by the high-phosphate diet but suppressed by the high-calcium diet, while paricalcitol reduced PTH without influencing phosphate or calcium. The high-calcium diet increased, while the high-phosphate diet reduced plasma calcium. Plasma calcitriol was significantly reduced in other remnant kidney groups, but further decreased after paricalcitol. Cardiac perivascular fibrosis and connective tissue growth factor were significantly increased in the remnant kidney groups, and further increased in paricalcitol-treated rats. Hence, regardless of the calcium, phosphate, or PTH levels, cardiac perivascular fibrosis and connective tissue growth factor increase in rats with renal insufficiency in association with low calcitriol. Possible explanations are that aggravated perivascular fibrosis after paricalcitol in renal insufficiency may be due to further suppression of calcitriol, or to a direct effect of the vitamin D analog.

Aims Mutations in cardiac ryanodine receptors (RyR2s) are linked to catecholaminergic polymorphic ventricular tachycardia (CPVT), characterized by risk of polymorphic ventricular tachyarrhythmias and sudden death during exercise. Arrhythmias are caused by gain-of-function defects in RyR2, but cellular arrhythmogenesis remains elusive. Methods and results We recorded endocardial monophasic action potentials (MAPs) at right ventricular septum in 15 CPVT patients with a RyR2 mutation (P2328S, Q4201R, and V4653F) and in 12 control subjects both at baseline and during epinephrine infusion (0.05 µg/kg/min). At baseline 3 and during epinephrine infusion, four CPVT patients, but none of the control subjects, showed delayed afterdepolarizations (DADs) occasionally coinciding with ventricular premature complexes. In order to study the underlying mechanisms, we expressed two types of mutant RyR2 (P2328S and V4653F) causing CPVT as well as wild-type RyR2 in HEK 293 cells. Confocal microscopy of Fluo-3 loaded cells transfected with any of the three RyR2s showed no spontaneous subcellular Ca2+ release events at baseline. Membrane permeable cAMP analogue (Dioctanoyl-cAMP) triggered subcellular Ca2+ release events as Ca2+ sparks and waves. Cells expressing mutant RyR2s showed spontaneous Ca2+ release events at lower concentrations of cAMP than cells transfected with wild-type RyR2. Conclusion CPVT patients show DADs coinciding with premature action potentials in MAP recordings. Expression studies suggest that DADs are caused by increased propensity of abnormal RyR2s to generate spontaneous Ca2+ waves in response to cAMP stimulation. Increased sensitivity of mutant RyR2s to cAMP may explain the occurrence of arrhythmias during exercise or emotional stress in CPVT.

Heme oxygenase-1 (HO-1) is an enzyme induced by hypoxia and reperfusion injury, and is associated with organ dysfunction in critically ill patients. Patients resuscitated from out-of-hospital cardiac arrest (OHCA) are subjected to hypoxemia, brain injury, and organ dysfunction. Accordingly, we studied HO-1 among these patients. A total of 143 OHCA patients resuscitated from a shockable initial rhythm and admitted to an ICU were included, with plasma HO-1 measured at ICU admission and at 24 h. We analyzed the associations between plasma HO-1 and time to return of spontaneous circulation (ROSC), 90-day mortality, and 12-month Cerebral Performance Category (CPC). HO-1 plasma concentrations were higher after OHCA compared with controls. HO-1 concentrations at admission and on day 1 associated with ROSC (P = 0.002 to P = 0.003). Admission and day 1 HO-1 plasma concentrations were higher in 90-day non-survivors than in survivors (P = 0.017, 0.026). In addition, poor neurological outcome (CPC 3-5) was associated with higher HO-1 plasma levels at admission (P = 0.024). Admission plasma HO-1 levels had an AUC of 0.623 to predict 90-day mortality and an AUC of 0.611 to predict CPC 3 to 5. In conclusion, we found that higher HO-1 plasma levels are associated with longer ROSC and poor long-term outcome.

In this study we examined diabetes- and hypertension-induced changes in cardiac structure and function in an animal model of type 2 diabetes, the Goto–Kakizaki (GK) rat. We hypothezised that treatment with omapatrilat, a vasopeptidase inhibitor, which causes simultaneous inhibition of angiotensin converting enzyme and neutral endopeptidase, provides additional cardioprotective effects, during normal- as well as high sodium intake, compared to treatment with enalapril, a selective inhibitor of angiotensin converting enzyme. Fifty-two GK rats were randomized into 6 groups to receive either normal-sodium (NaCl 0.8%) or high-sodium (NaCl 6%) diet and enalapril, omapatrilat or vehicle for 12 weeks. The GK rats developed hypertension, cardiac hypertrophy and overexpression of cardiac natriuretic peptides and profibrotic connective tissue growth factor compared to nondiabetic Wistar rats. The high dietary sodium further increased the systolic blood pressure, and changed the mitral inflow pattern measured by echocardiography towards diastolic dysfunction. Enalapril and omapatrilat equally decreased the systolic blood pressure compared to the control group during normal- as well as high-sodium diet. Both drugs had beneficial cardioprotective effects, which were blunted by the high dietary sodium. Compared to enalapril, omapatrilat reduced the echocardiographically measured left ventricular mass during normal-sodium diet and improved the diastolic function during high-sodium diet in GK rats. Furthermore, omapatrilat reduced relative cardiac weight more effectively than enalapril during high sodium intake. Our results suggest that both the renin–angiotensin and the neutral endopeptidase system are involved in the pathogenesis of diabetic cardiomyopathy since vasopeptidase inhibition was shown to provide additional benefits in comparison with selective angiotensin converting enzyme inhibition alone.

BACKGROUND The renin-angiotensin system plays an important role in the pathogenesis of diabetes-induced vascular and renal complications. Vasopeptidase inhibitors simultaneously inhibit angiotensin-converting enzyme (ACE) and neutral endopeptidase. OBJECTIVE To compare the effectiveness of vasopeptidase inhibition and ACE inhibition in preventing hypertension, endothelial dysfunction and diabetic nephropathy in spontaneously diabetic Goto-Kakizaki (GK) rats. METHODS Eight-week-old GK rats received omapatrilat (40 mg/kg) or enalapril (30 mg/kg) for 12 weeks, either during a normal-sodium or high-sodium diet (7% w/w). Blood pressure, arterial functions and renal morphology were determined. RESULTS Blood pressure and albuminuria were increased in GK rats compared to non-diabetic Wistar controls. Endothelium-dependent vascular relaxation in response to acetylcholine (ACh) and endothelium-independent vascular relaxation in response to sodium nitroprusside (SNP) were impaired in GK rats. Experiments with N-nitro-L-arginine methyl ester (L-NAME), diclofenac, and L-NAME + diclofenac suggested that cyclooxygenase and endothelium-derived hyperpolarizing factor components of endothelium-dependent vascular relaxation were also impaired. A high-sodium diet aggravated hypertension and diabetes-induced vascular and renal complications. Omapatrilat and enalapril normalized blood pressure and albuminuria during the normal-sodium diet, and effectively ameliorated diabetes-induced renal complications also during the high-sodium diet. However, omapatrilat improved endothelium-dependent relaxation to ACh to a greater extent (85 +/- 5%) than enalapril (68 +/- 6%, P < 0.05). Diclofenac pre-incubation eliminated this difference between omapatrilat and enalapril in ACh-induced vascular relaxation, suggesting that it was mediated, at least in part, via the cyclooxygenase pathway. CONCLUSIONS Despite comparable blood pressure-lowering and renoprotective properties, omapatrilat may be more effective in preventing vascular dysfunction during diabetes compared to enalapril in GK rats.

The regulation of both angiotensin receptors and bradykinin receptors during sodium intake is poorly understood. We hypothesized that an altered balance between renal angiotensin type 1 (AT1) receptors and bradykinin type 2 (B2) receptors might contribute to an increase in blood pressure during periods of high-sodium intake. We studied the effects of high-sodium intake on renal AT1 receptors and B2 receptors in 5-6-week-old spontaneously hypertensive rats (SHR) receiving high-sodium chloride (6% NaCl) or mineral salts (10.5%, composition: 57% NaCl, 28% KCl, 12% MgSO4) compared to those receiving a low-sodium (NaCl 0.125%) diet for 10 weeks. Mineral salt intake was included due to its beneficial effects on blood pressure and cardiac hypertrophy. Receptor densities were measured by quantitative autoradiography. AT1 receptors were quantified using incubation with 125I-Sar1-Ile8-angiotensin II and displacement was measured with PD123319 (10 micromol/l), whereas B2 receptors were quantified using 125I-HPP-icatibant and displacement was measured with icatibant (3 micromol/l). Compared to the SHR controls, a further increase in blood pressure occurred after 2 weeks in the 6% NaCl group and after 6 weeks in the mineral salt group. AT1 receptor density increased in the renal cortex by 41% (p

Objective To characterize novel type of mutations of the epithelial sodium channel (ENaC) β or γ subunits in patients with Liddle's syndrome, an autosomal dominant form of hypertension.Patients and methods DNA samples from two probands with early-onset, treatment-resistant hypertension and suppresse

Aims: We investigated angiotensin II and nitric oxide-cGMP pathway in the development of hypertension and renal damage in chronic experimental nephritis. Methods: Rats with autoimmune nephritis were treated for 12 weeks with AT1 receptor antagonist L-158,809 and/or ACE inhibitor captopril given in drinking water. Blood pressure, urinary albumin, and urinary excretion of cGMP were measured. Renal density of ACE, AT1 and AT2 receptors was determined by quantitative in vitro autoradiography. Results: L-158,809, captopril, and their combination decreased blood pressure and normalised urinary albumin excretion rate in rats with nephritis. In L-158,809-treated rats, cGMP excretion was increased compared to the vehicle-treated nephritic group suggesting that the dysfunctional nitric oxide system may be activated by angiotensin antagonism. In nephritic rats, AT1 and AT2 receptor binding densities in renal medulla were decreased, cortical AT receptor expression remained unchanged. Following L-158,809 treatment, both AT1 and AT2 receptor binding was suppressed. Conclusion: Long-term blockade of AT1 receptors in chronic nephritis has beneficial effects both on albuminuria and blood pressure being as effective as ACE inhibition or their combination. The stimulatory effect of AT1 receptor antagonism on cGMP production was not mediated by AT2 receptor-dependent mechanisms suggesting that AT1 receptor blockade per se favours activation of humoral pathways that stimulate cGMP production and potentially contribute to renal protection in chronic nephritis.

In a Phase III randomized trial (EMPA-REG BP™), patients with type 2 diabetes (T2DM) and hypertension (defined as mean seated office systolic blood pressure [SBP] 130-159 mmHg and diastolic BP [DBP] 80-99 mmHg at screening) received empagliflozin (EMPA) 10 mg (n=276), EMPA 25 mg (n=276) or placebo (PBO; n=271) once daily in the morning for 12 weeks (mean [SD] age 60.2 [9.0] yrs, HbA1c 7.90 [0.74] %, 24-h SBP 131.4 [12.3] mmHg, 24-h DBP 75.0 [7.8] mmHg). We assessed changes from baseline in SBP (mean 24-h, awake-time, sleep-time) via ambulatory BP monitoring at week 12 in patients categorized as dippers (sleep-time mean SBP ≤90% of awake-time mean; n=417) or non-dippers (sleep-time mean SBP >90% of awake-time mean; n=350). Baseline mean (SD) 24-h SBP (mmHg) was 129.9 (11.6) in dippers and 133.1 (12.4) in non-dippers. Adjusted mean (SE) changes from baseline in mean 24-h SBP (mmHg) in dippers were -0.2 (0.7) with PBO vs -3.8 (0.6) and -3.9 (0.7) with EMPA 10 and 25 mg, respectively (both p In patients with T2DM and hypertension, EMPA 10 mg and 25 mg significantly reduced SBP vs PBO in dippers and non-dippers.

The sodium glucose cotransporter 2 inhibitor empagliflozin (EMPA) reduces HbA1c, weight and blood pressure (BP) in patients with type 2 diabetes (T2D). While glucose lowering with EMPA is dependent on renal function, the impact of chronic kidney disease (CKD) on BP reduction with EMPA is less well understood. Our aim was to determine if impaired renal function attenuates antihypertensive effects of EMPA. A Phase III randomized placebo (PBO)-controlled trial (EMPA-REG BP™) investigated the efficacy and safety of EMPA in patients with T2D and hypertension (defined as mean seated office systolic BP [SBP] 130-159 mmHg and diastolic BP [DBP] 80-99 mmHg at screening). Patients (mean [SD] age 60.2 [9.0] years, HbA1c 7.90 [0.74] %, 24-hour SBP 131.4 [12.3] and 24-hour DBP 75.0 [7.8] mmHg) received EMPA 10 mg (n=276), EMPA 25 mg (n=276) or PBO (n=271) once daily for 12 weeks. We assessed changes from baseline in mean ambulatory 24-hour SBP and HbA1c in subgroups by baseline eGFR (MDRD equation), adjusting for differences in baseline mean 24-hour SBP (for SBP analyses only), HbA1c, region, number of antihypertensive medications, treatment, eGFR and treatment by eGFR interaction between groups. In patients with normal renal function, or stage 2 or 3 CKD, EMPA significantly reduced HbA1c and mean 24-hour SBP vs PBO (Table). As expected, PBO-corrected HbA1c reductions with EMPA appeared to decrease with decreasing eGFR (Table). In contrast, PBO-corrected reductions in mean 24-hour SBP with EMPA mostly appeared to increase with decreasing eGFR (Table). Unlike HbA1c, mean 24-hour SBP reductions with EMPA in patients with T2D and hypertension appear to be greater in patients with lower eGFR, indicating that SBP modulation with EMPA may involve pathways other than urinary glucose excretion such as diuretic effects, weight loss, improved glycemic control, reduced arterial stiffness or direct vascular effects.

The pharmacological profile of a vasopeptidase inhibitor is dependent on the ratio of neutral endopeptidase (NEP) vs angiotensin converting enzyme (ACE) inhibition of the particular drug. We used in vitro autoradiography to determine the local renal and cardiac NEP and ACE inhibition after oral treatment with the dual NEP/ACE inhibitor omapatrilat in rat. Maximal inhibition of both renal NEP and ACE was achieved at the omapatrilat dose of 40 mg kg −1 day −1 . Effective local ACE inhibition was detected also in the myocardium. The haemodynamic effects were similar to captopril, but omapatrilat treatment produced more favorable effect on natriuretic peptide levels. In conclusion, good tissue penetration of omapatrilat and balanced NEP/ACE inhibition may prove to be useful in the treatment of hypertension and heart failure.

We investigated the role of cardiomyocyte apoptosis in the remodeling of the left ventricle from 24 h to 12 wk after myocardial infarction in the rat. Infarct size planimetry, quantification of cardiomyocyte apoptosis, terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) methodology, and echocardiography (left ventricular diastolic diameter and ejection fraction) were performed. Sham-operated animals showed low rates of cardiomyocyte apoptosis (0.03%) and no change in diastolic diameter or ejection fraction during the study. Twenty-four hours after infarction, TUNEL positivity was high in the infarct areas (1.4%) and border zones (4.9%). It declined to 0.34% ( P < 0.01 vs. sham) at 4 wk and 0.10% at 12 wk in the border zones. In the remote myocardium, cardiomyocyte apoptosis increased to 0.07% ( P = 0.03 vs. sham) on day 1 and remained on the same level up to 4 wk. The increase in diastolic diameter 1–4 wk after infarction correlated ( r = 0.60, P < 0.01) with cardiomyocyte apoptosis in the noninfarcted myocardium, which quantitatively contributed most (>50%) to the apoptotic cell loss by 4 wk.

Endothelial dysfunction is associated with hypertension, hypercholesterolemia, and heart failure. We tested the hypothesis that spontaneously diabetic Goto-Kakizaki (GK) rats, a model for type 2 diabetes, exhibit endothelial dysfunction. Rats also received a high-sodium diet (6% NaCl [wt/wt]) and chronic angiotensin type 1 (AT 1 ) receptor blockade (10 mg/kg PO valsartan for 8 weeks). Compared with age-matched nondiabetic Wistar control rats, GK rats had higher blood glucose levels (9.3±0.5 versus 6.9±0.2 mmol/L for control rats), 2.7-fold higher serum insulin levels, and impaired glucose tolerance (all P P P P N G -nitro- l -arginine methyl ester and the cyclooxygenase inhibitor diclofenac inhibited relaxations to acetylcholine almost completely in GK rats but not in Wistar rats, suggesting that endothelial dysfunction can be in part attributed to reduced relaxation via arterial K + channels. Perivascular monocyte/macrophage infiltration and intercellular adhesion molecule-1 overexpression were observed in GK rat kidneys. A high-sodium diet increased blood pressure by 24 mm Hg and 24-hour albuminuria by 350%, induced cardiac hypertrophy, impaired endothelium-dependent relaxation further, and aggravated inflammation (all P 2α , a vasoconstrictor and antinatriuretic arachidonic acid metabolite produced by oxidative stress, was increased 400% in GK rats on a high-sodium diet. Valsartan decreased blood pressure in rats fed a low-sodium diet and prevented the inflammatory response. In rats fed a high-sodium diet, valsartan did not decrease blood pressure or improve endothelial dysfunction but protected against albuminuria, inflammation, and oxidative stress. As measured by quantitative autoradiography, AT 1 receptor expression in the medulla was decreased in GK compared with Wistar rats, whereas cortical AT 1 receptor expression, medullary and cortical angiotensin type 2 (AT 2 ) receptor expressions, and adrenal ACE and neutral endopeptidase expressions were unchanged. A high-sodium diet did not influence renal AT 1 , AT 2 , ACE, or neutral endopeptidase expressions. In valsartan-treated GK rats, the cortical and medullary AT 1 receptor expressions were decreased in the presence and absence of a high-sodium diet. A high-sodium diet increased plasma brain natriuretic peptide concentrations in presence and absence of valsartan treatment. We conclude that hypertension in GK rats is salt sensitive and associated with endothelial dysfunction and perivascular inflammation. AT 1 receptor blockade ameliorates inflammation during a low-sodium diet and partially protects against salt-induced vascular damage by blood pressure–independent mechanisms.

Serum ACE activity increased as expected about three-fold following six weeks of captopril (30 mg/kg/day) treatment in Wistar rats (n = 9). The effect on serum and lung ACE activity and concentration, respectively, was studied after captopril discontinuation. Serum ACE activity was measured at start and 3, 6, and 12 days after captopril withdrawal. The approximal half-life of serum ACE activity was 72 hours as judged from the decrease rate after stimulated ACE biosynthesis induced by captopril. No differences in lung plasma membranes and lung homogenate ACE concentrations between treated and untreated rats were observed 12 days after discontinuation of captopril treatment. Serum ACE activity remained unchanged in the control rats (n = 9). We conclude that induction of ACE biosynthesis in the rat is reversible after withdrawal of captopril.

Abstract —It has been suggested that combined inhibition of angiotensin-converting enzyme (ACE) and neutral endopeptidase (NEP) may lower blood pressure more effectively than either treatment alone, independent of the degree of salt and volume status or the activity of the renin-angiotensin system. The effects of NEP inhibition in hypertension associated with diabetes mellitus are largely unknown. We therefore compared ACE inhibition, NEP inhibition, and dual NEP/ACE inhibition in diabetic hypertensive rats. Spontaneously hypertensive rats (SHR) aged 9 to 10 weeks were injected with either streptozotocin (45 mg/kg) or citrate buffer and randomized to receive either the ACE inhibitor captopril (25 mg/kg BID), the NEP inhibitor SCH 42495 (30 mg/kg BID), the dual NEP/ACE inhibitor S 21402 (25 or 50 mg/kg BID), or vehicle by gavage for 4 weeks. A group of diabetic SHR was also allocated to receive the combination of SCH 42495 (30 mg/kg BID) and captopril (25 mg/kg BID). The degree of renal NEP inhibition was determined by autoradiography, and plasma renin activity (PRA) was determined by radioimmunoassay. In diabetic SHR, the dual NEP/ACE inhibitor (50 mg/kg BID), as well as the combination of the NEP inhibitor and the ACE inhibitor, reduced systolic blood pressure more effectively than the ACE inhibitor ( P P P P P

Objective: The mechanism of postthoracotomy atrial fibrillation (AF) could be related to right ventricular (RV) strain. The effect of oxygen on the occurrence of postoperative AF and on RV function was studied. Design: A prospective, randomized study. Setting: A university hospital. Participants: Twenty-four noncardiac thoracotomy patients. Interventions: At the end of the postoperative anesthesia care unit period, the patients were randomly allocated to receive 35% oxygen until either the third (P = prolonged group) or the first postoperative morning (S = short group). Measurements and Main Results: Measurement of hemodynamic variables using a thermodilution pulmonary artery catheter, oxygenation, concentration of plasma atrial natriuretic peptide (ANP) and Holter monitoring were started preoperatively and continued for the 3 postoperative days (PODs). Systolic RV pressure (systolic RVP) and pulmonary vascular resistance (PVR) increased postoperatively only in group S. Major changes in RV performance were not seen with echocardiography or the thermodilution method in any patient. Silent episodes of AF occurred in three patients (25%) in group P and in one patient (8%) in group S (not significant [NS]) without deviations in plasma ANP concentration. On each of the 3 PODs, all patients were exposed to 60% oxygen for 15 minutes. Systolic RVP decreased significantly during the exposure to 60% oxygen only in group S, but not in patients developing AF. Predictive factors for AF were a high preoperative PVR, intraoperative bleeding necessitating volume loading, and elevated systolic RVP immediately after thoracotomy. Conclusion: Short episodes of AF occurred irrespective of the length of oxygen therapy. Occurrence of AF could not be explained by changes in RV function.

Carbon dioxide (CO,) insufflation with increased intraabdominal pressure (IAP) has adverse hemodynamic, pulmonary, and renal effects. To avoid these problems, an abdominal wall lift method with a retractor was used to provide the surgical view without CO2 insufflation. Twenty-six patients undergoing elective laparoscopic cholecystectomy were randomly allocated to either the gasless, retractor group, or conventional CO, pneurnoperitoneum group (CPP). Hemodynamic data, ventilatory variables, urine output, urine oxygen tension, and blood samples for determining stress hormones were collected throughout the perioperative period. Patients in the retractor group had lower mean arterial pressure, heart rate, and central venous pressure (P < 0.001). They also had higher pulmonary dynamic compliance and needed a lower minute volume of ventilation to achieve normocarbia (P < 0.001). Urine output and oxygen tension in urine were higher (P < 0.05) with the retractor method than with CPP. Increase in plasma renin activity (P < 0.05) and decrease in core temperature (P < 0.001) were smaller with the gasless method than with CPP. The gasless method for laparoscopic cholecystectomy might be beneficial, especially in patients with compromised cardiorespiratory or renal function. Implications: Totally gasless laparoscopic cholecystectomy was compared with conventional pressure pneumoperitoneum with CO, insufflation. The gasless method resulted in more stable hemodynamics and pulmonary function, as well as higher urine, output than conventional pressure pneumoperitoneum. No changes in renal oxygenation was seen with the gasless method, compared with conventional pressure pneumoperitoneum.

Objectives. To examine associations of N-terminal and C-terminal components of the proatrial natriuretic peptide [ANP (1-98) and ANP (99-126), respectively], with echocardiographic measurements of left ventricular structure and performance and with the function of the aortic and mitral valves in old age. To compare the predictive value of the atrial peptides and echocardiographic data for short-term mortality. Design. A population-based survey with 1.5-year mortality follow-up. Setting. University hospital. Subjects. Three-hundred and thirty-three people aged 78-88 years. Main outcome measures. (i) Plasma ANP (1-98) and ANP (99-126) : (ii) M-mode and Doppler echocardiographic measurements of left atrial diameter; left ventricular diameters, mass and fractional shortening ; peak transmitral velocities; aortic valve area, aortic regurgitation jet length and mitral regurgitant jet area; (iii) total and cardiovascular 1.5-year mortality. Results. ANP (1-98) correlated with left atrial diameter (r = 0.33; P < 0.001), left ventricular mass (r = 0.19; P < 0.001), fractional shortening (r = -0.16; P < 0.01) and the early-to-atrial peak transmitral velocity ratio (r = 0.23; P < 0.001). Also, ANP (1-98) predicted the degree of aortic valve obstruction and the severity of aortic and mitral regurgitation. Associations of ANP (99-126) with echocardiographic data were much weaker. Aortic valve stenosis and ANP (1-98) were independent predictors of age-and sex-adjusted total and cardiovascular mortality at 1.5 years of entry. Conclusions. Circulating ANP (1-98) correlates with left atrial size, with left ventricular mass and performance and with the severity of aortic and mitral valve dysfunction in persons representing the general elderly population. ANP (1-98) also predicts both total and cardiovascular mortality.