OBJECTIVETo observe the effects of combined beta(1) adrenergic receptor (AR) antagonist with beta(2)AR agonist therapy on cardiac function and cardiomyocyte apoptosis in heart failure rats.

METHODSHeart failure was induced by isoproterenol and rats were randomly divided into metoprolol group (50 mg/kg twice daily/gavage, n = 11), combined treatment group (fenoterol 125 microg/kg and metoprolol 50 mg/kg twice daily/gavage, n = 11) and placebo group (saline, n = 10), another normal 9 male Wistar rats served as control group. After 8 weeks' treatment, cardiac function, apoptosis index (AI), Caspase-3 activity, expression levels of bcl-2 and bax protein, organ weight/body weight and collagen volume fraction (CVF) were evaluated.

RESULTS(1) Left ventricular end diastolic dimension, left ventricular end systolic dimension and E/A ratio were significantly increased and fractional shortening, ejection fraction significantly reduced post isoproterenol (all P < 0.05 vs. control) and these changes were significantly attenuated by metoprolol alone (all P < 0.05 vs. placebo) and further attenuated by the metoprolol and fenoterol combination therapy (all P < 0.05 vs. placebo and metoprolol). (2) Left ventricular weight to body weight ratio, lung weight to body weight ratio and CVF were also significantly reduced in metoprolol and combined treatment group than those in placebo group (all P < 0.01). (3) Compared with placebo group, AI and Caspase-3 activity were significantly lower in metoprolol group (all P < 0.01 vs. placebo) and further reduced in combined treatment group (all P < 0.01 vs. metoprolol). (4) The expression level of bax protein was significantly lower in metoprolol group while bcl-2/bax significantly higher than those in placebo group. These changes were more significant in combined treatment group (all P < 0.01 vs. metoprolol).

CONCLUSIONSbeta(1)AR antagonist in combination with beta(2)AR agonist further improved the cardiac function and prevented cardiac remodeling compared with using beta(1)AR antagonist alone in heart failure rats. Downregulated bax and upregulated bcl-2/bax expressions might contribute to the observed beneficial therapy effects by reducing cardiomyocyte apoptosis in these animals.

Adrenergic beta-1 Receptor Antagonists ; Adrenergic beta-2 Receptor Agonists ; Adrenergic beta-Agonists ; pharmacology ; therapeutic use ; Adrenergic beta-Antagonists ; pharmacology ; therapeutic use ; Animals ; Apoptosis ; drug effects ; Drug Therapy, Combination ; Heart Failure ; drug therapy ; Male ; Myocytes, Cardiac ; cytology ; Rats ; Rats, Wistar ; Ventricular Remodeling

BACKGROUNDStimulation of the heart beta 3-adrenoceptor (AR) may result in a negative inotropic effect. Being up-regulated, beta 3-AR plays a more important role in the regulation of cardiac function during heart failure. However, the effect of chronic blocking of beta 3-AR on heart failure has not been fully elucidated. In this study, we used a selective beta 3-AR antagonist SR59230A to treat a well defined heart failure rat model chronically, then evaluated its effect on cardiac function and investigated the mechanism.

METHODSMale Wistar rats were chosen randomly as controls (n = 8). Isoproterenol induced heart failure rats were randomly divided into ISO group (n = 10) and SR group (n = 10). The ISO group received intraperitoneal injection of 1 ml saline twice a day; the SR group received intraperitoneal injection of SR59230A 85 nmol in 1 ml saline twice a day; and the control group received no treatment. The treatment was started 24 hours after the last isoproterenol injection and continued for 7 weeks. Then we measured the following indexes: the ratio of heart weight to body weight (HW/BW) and the ratio of left ventricular weight to body weight (LVW/BW), collagen volume fraction (CVF), left ventricular end diastolic dimension (LVEDd), left ventricular end systolic dimension (LVESd), ejection fraction (EF), fractional shortening (FS) and the ratio of E wave to A wave (E/A), the mRNA and protein expression of beta 3-AR and eNOS, and cGMP level in the heart.

RESULTSThe ratios HW/BW and LVW/BW were significantly increased in the ISO group compared with the control group (P < 0.01), but they were limited in the SR group (P < 0.05 compared with the ISO group). CVF increased in the ISO group and the SR group (P < 0.01), but it was significantly attenuated in the SR group (P < 0.01). LVEDd, LVESd and E/A ratio were significantly increased in the ISO group compared with the control group (P < 0.01), while EF and FS were significantly decreased (P < 0.01). Compared with the ISO group, the SR group showed that LVEDd, LVESd and E/A ratio were significantly decreased (P < 0.01), whereas EF and FS were significantly increased (P < 0.01). beta(3)-AR and eNOS mRNA and protein in the ISO group were significantly increased when compared with the control group (P < 0.01). These increases were all attenuated in the SR group compared with the ISO group (P < 0.01). The level of cGMP in myocardial tissue was significantly increased in the ISO group compared with the control group (P < 0.01), whereas SR59230A treatment normalized this increment (P < 0.01).

CONCLUSIONSChronic blocking of beta 3-AR could ameliorate cardiac function in heart failure rats and its mechanism involves inhibition of the negative inotropic effect and attenuation of cardiac remodeling.

Adrenergic beta-3 Receptor Antagonists ; Adrenergic beta-Antagonists ; pharmacology ; therapeutic use ; Animals ; Blotting, Western ; Disease Models, Animal ; Echocardiography ; Enzyme-Linked Immunosorbent Assay ; Heart Failure ; drug therapy ; physiopathology ; Male ; Myocardium ; pathology ; Nitric Oxide Synthase Type III ; genetics ; Propanolamines ; pharmacology ; Rats ; Rats, Wistar ; Receptors, Adrenergic, beta-3 ; physiology ; Reverse Transcriptase Polymerase Chain Reaction ; Ventricular Function, Left ; drug effects

OBJECTIVETo examine serum B-type natriuretic peptide (BNP) levels and BNP expression of protein and mRNA in the right ventricular myocardium in juvenile rats with right heart failure (RHF) and the effects of beta-adrenergic receptor blocker carvedilol on serum and myocardial BNP levels in order to investigate the role of BNP in the diagnosis and treatment of RHF.

METHODSFifty-one four-week-old Sprague-Dawley rats were randomly assigned to 5 groups: RHF 1, RHF 2, carvedilol-treated RHF, control 1 and control 2. RHF was developed 4 weeks after an intraperitoneal injection of monocrotaline in the RHF 1, RHF 2 and carvedilol-treated RHF groups. The rats in the RHF 1 and the control 1 groups were sacrificed after the RHF event for observing pathological changes in the myocardium. After the RHF event, the carvedilol-treated group was given intragastric administration of carvedilol (3.5 mg/kg/d) for 2 weeks. The RHF 2 and the control 2 groups were given distilled water of equal dose instead. The rats were sacrificed 2 weeks after carvedilol or distilled water administration. Serum BNP levels were measured using ELISA. BNP protein and mRNA expression in the right ventricular myocardium were measured by immunohistochemistry and RT-PCR, respectively. Haemodynamics and some physiological indexes were measured.

RESULTSSerum BNP levels and BNP protein and mRNA expression in the right ventricular myocardium were significantly higher in the RHF 1 group than those in the control 1 group (p<0.01). Serum BNP levels and BNP protein and mRNA expression in the right ventricular myocardium increased more significantly in the RHF 2 group. There was a positive correlation between serum BNP levels and myocardial BNP protein expression in the RHF group (r=0.698, p<0.01). Serum BNP levels and BNP protein and mRNA expression in the carvedilol-treated RHF group were significantly reduced when compared with the RHF 2 group (p<0.05). Carvedilol treatment also resulted in improved hemodynamics and relieved right ventricular hypertrophy.

CONCLUSIONSBNP may serve an index for the diagnosis of RHF and the evaluation of severity in children with RHF. Carvedilol shows protections against RHF caused by pressure load.

Adrenergic beta-Antagonists ; pharmacology ; Animals ; Carbazoles ; pharmacology ; therapeutic use ; Heart Failure ; blood ; drug therapy ; pathology ; physiopathology ; Natriuretic Peptide, Brain ; blood ; genetics ; Propanolamines ; pharmacology ; therapeutic use ; RNA, Messenger ; analysis ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: In this study, there was an investigation as to whether there is a functional difference in essential tremor (ET), according to responses to beta-blockers, by evaluating regional changes in cerebral glucose metabolism. MATERIALS AND METHODS: Seventeen male patients with ET were recruited and categorized into two groups: 8 that responded to medical therapy (group A); and 9 that did not respond to medical therapy (group B). Eleven age-sex matched healthy control male subjects were also included in this study. All subjects underwent F-18 fluorodeoxyglucose (FDG)-PET, and evaluated for their severity of tremor symptoms, which were measured as a score on the Fahn-Tolosa-Marin tremor rating scale (FTM). The FDG-PET images were analyzed using a statistical parametric mapping program. RESULTS: The mean FTM score 6 months after the initiation of propranolol therapy was significantly lower in group A (18.13 > 8.13), compared with group B (14.67 = 14.67). The glucose metabolism in group A in the left basal ganglia was seen to be decreased, compared with group B. The ET showed a more significantly decreased glucose metabolism in both the fronto-temporo-occipital lobes, precuneus of right parietal lobe, and both cerebellums compared with the healthy controls. CONCLUSION: Essential tremor is caused by electrophysiological disturbances within the cortical-cerebellar networks and degenerative process of the cerebellum. Furthermore, ET may have different pathophysiologies in terms of the origin of disease according to the response to first-line therapy.
Adrenergic beta-Antagonists/*pharmacology/therapeutic use ; Aged ; Brain/*drug effects/metabolism/radiography ; Brain Mapping ; Essential Tremor/*diagnosis/drug therapy/radiography ; Fluorodeoxyglucose F18/*chemistry ; Glucose/*metabolism ; Humans ; Male ; Middle Aged ; *Positron-Emission Tomography ; Propranolol/pharmacology/therapeutic use ; Radiopharmaceuticals/*chemistry

OBJECTIVETo evaluate the efficacy and safety of long-term treatment with arotinolol in patients with idiopathic dilated cardiomyopathy (IDCM).

METHODSSixty-three patients with IDCM were evaluated at baseline and after 12-month therapy with arotinolol. The conventional therapy for congestive heart failure was continued throughout the study with arotinolol as the only beta-blocker. Left ventricular function was assessed with the New York Heart Association functional class and two-dimensional echocardiography.

RESULTSAfter 12-month arotinolol treatment, there was a significant improvement in left ventricular systolic function. Left ventricular end-systolic dimension significantly decreased from 59.52 +/- 8.83 mm to 50.89 +/- 8.17 mm (P < 0.001). Left ventricular ejection fraction significantly increased from 27.39% +/- 7.94% to 41.13% +/- 9.45% ( P < 0.001). Left ventricular mass index decreased from 150.47 +/- 42.42 g/m2 to 141.58 +/- 34.36 g/m2 (P < 0.01). No adverse events leading to premature discontinuation of study drug occurred.

CONCLUSIONIn this preliminary study, 12-month arotinolol treatment has a favorable effect on left ventricular function in patients with IDCM, and it is safe and well tolerated.

Adrenergic beta-Antagonists ; adverse effects ; pharmacology ; therapeutic use ; Adult ; Cardiomyopathy, Dilated ; drug therapy ; physiopathology ; Echocardiography ; Female ; Humans ; Male ; Middle Aged ; Propanolamines ; adverse effects ; pharmacology ; therapeutic use ; Ventricular Function, Left ; drug effects

OBJECTIVETo assess the effect of beta blocker on blood flow velocity and reserve on the intramural coronary artery of patients with myocardial bridging.

METHODSIn 8 patients with myocardial bridge, intracoronary Doppler was performed before and after esmolol was given intravenously. The basic average peak velocity (bAPV), hyperaemic average peak velocity (hAPV) of blood flow, and coronary flow reserve (CFR) proximal and distal to the mural myocardial bridging was measured and compared.

RESULTSAfter esmolol injection, the mural coronary diameter systolic reduction decreased from (58.0 +/- 14.7)% to (26.0 +/- 9.8)% (P < 0.01); the bAPV proximal and distal to myocardial bridging separately decreased from (19.4 +/- 4.9) cm/s and (18.4 +/- 3.6) cm/s to (4.7 +/- 3.9) cm/s (P < 0.01) and (15.1 +/- 1.5) cm/s (P < 0.05). Under hyperemization, esmolol changed the hAPV of proximal and distal to myocardial bridging separately from (54.1 +/- 14.9) cm/s and (44.7 +/- 9.4) cm/s to (49.7 +/- 16.4) cm/s and (48.9 +/- 10.1) cm/s (all P > 0.05); thus, the value of CFR both proximal and distal to myocardial bridge increased separately from 2.8 +/- 0.3 and 2.5 +/- 0.5 to 3.4 +/- 0.5 and 3.2 +/- 0.6 (all P < 0.01).

CONCLUSIONEsmolol can decreased the compression of the intramural coronary artery and increased the CFR to normal level of it.

Adrenergic beta-Antagonists ; pharmacology ; therapeutic use ; Coronary Circulation ; drug effects ; physiology ; Coronary Vessels ; diagnostic imaging ; drug effects ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Myocardial Bridging ; drug therapy ; physiopathology ; ultrastructure ; Propanolamines ; pharmacology ; therapeutic use ; Ultrasonography, Interventional

OBJECTIVEWe used the individual patient data from clinical trials, pooled in the INDANA data set, to explore whether blood pressure reduction was related to the baseline individual characteristics, and quantify the potential associations.

METHODSWe used the data from 31 140 patients with essential hypertension recruited in four randomized placebo-controlled clinical trials, MRC35-64, MRC65-74, STEP and SYST-EU. Thiazide diuretics, &beta;-blocker, and calcium channel blocker, three of six major BP lowering drugs were analyzed. Patients were all with the same first dosage of the drug in each trial. Age, body weight, height, level of total cholesterin (TC), systolic blood pressure (SBP) and diastolic blood pressure (DBP) when initialed and at first visit of follow-up, pharmacological treatment, gender, status of smoking, history of myocardium infarction were factors taken into model. Data were managed by software SAS(®). Statistical analyses were performed with SAS(®) and R. Model was developed to evaluate the relationship between decrease of SBP and characteristics of patients.

RESULTSInitial SBP is the only modifier of treatment effect on SBP response in the 3 BP lowering drug classes (&beta; = 0.09, 0.37 and 0.18, respectively). Age and initial DBP were factors significantly correlated with SBP fall for diuretic (&beta; = 0.17 and 0.14), and age was one of factors significantly correlated with SBP fall for &beta;-blocker (&beta; = -0.17). Smokers would receive less SBP fall compare to non-smokers in &beta;-blocker active treated group (&beta; = -2.07). There is converse effect of age between the diuretic and &beta;-blocker; older people seem sensitive to diuretic, while young people are sensitive to &beta;-blocker. As to calcium channel antagonist class, body weight is another modifier (&beta; = 0.06) (All P value are 0.000 except 0.050 for body weight in calcium channel antagonist class).

CONCLUSIONWe identified 5 significant modifiers (baseline SBP and DBP, age, smoking status and body weight) for SBP response to treatment effect, while gender, TC and history of myocardial infarction are not modifiers for SBP response to treatment effect.

Adrenergic beta-Antagonists ; pharmacology ; therapeutic use ; Adult ; Age Factors ; Aged ; Antihypertensive Agents ; pharmacology ; therapeutic use ; Blood Pressure ; Body Weight ; Calcium Channel Blockers ; pharmacology ; therapeutic use ; Female ; Humans ; Hypertension ; drug therapy ; physiopathology ; Male ; Middle Aged ; Models, Theoretical ; Randomized Controlled Trials as Topic ; Smoking ; Sodium Chloride Symporter Inhibitors ; pharmacology ; therapeutic use ; Systole

OBJECTIVETo investigate the effect of low-dose carvedilol combined with candesartan in the prevention of acute and chronic cardiotoxicity of anthracycline drugs in adjuvant chemotherapy of breast cancer.

METHODSForty patients were randomly divided into two groups: the experimental group with chemotherapy plus low-dose carvedilol combined with candesartan (20 cases) and control group with chemotherapy alone (20 cases). The same chemotherapy was given to the two groups. All the 40 patients had no contraindication for carvedilol and candesartan. Patients of the experimental group received low-dose carvedilol from 2.5 mg orally twice a day at first cycle to 5 mg twice a day gradually if no side reactions, and candesartan 2.5 mg orally once a day. Electrocardiogram, ultrasonic cardiogram, arrhythmia, troponin and non-hematologic toxicity were recorded and compared after the second, forth and sixth cycle of chemotherapy. Each cycle included 21 days.

RESULTSLVEF was decreased along with the prolongation of chemotherapy in the experimental group and control group. LVEDD and LVESD showed no significant changes in the experimental group, but gradually increased in the control group. After four and six cycles of chemotherapy, LVEF were (57.00 ± 5.13)% and (45.95 ± 3.68)%, respectively, in the control group, significantly lower than that of (67.00 ± 5.13)% and (57.50 ± 2.57)%, respectively, in the experimental group (P < 0.05). After six cycles of chemotherapy, LVEDD and LVESD were (50.00 ± 10.48) mm and (35.01 ± 2.99) mm, respectively, in the control group, significantly higher than those before chemotherapy (P < 0.05) and experimental group (P < 0.001). The rate of ST segment and T wave abnormalities was 80.0% in the control group after six cycles of chemotherapy, significantly higher than that of 25.0% after four cycles of chemotherapy (P = 0.001) and 10.0% after two cycles of chemotherapy (P < 0.001). The reduction of QRS voltage, arrhythmia and abnormal troponin were 55.0%, 45.0% and 45.0%, respectively, in the control group, significantly higher than those in the experimental group (20.0%, P < 0.05), (10.0%, P = 0.010) and (10.0%, P < 0.05), respectively. The rate of abnormal expression of troponin was 45.0% in the control group, significantly higher than the 10.0% in the experimental group (P < 0.05).

CONCLUSIONSThe use of low-dose carvedilol combined with candesartan can reduce the acute and chronic cardiotoxicity of anthracycline drugs, and with tolerable toxicities. This may provide a new approach to prevent cardiotoxicity of anthracycline drugs in adjuvant chemotherapy of breast cancer.

Adrenergic beta-Antagonists ; administration & dosage ; pharmacology ; Adult ; Aged ; Angiotensin II Type 1 Receptor Blockers ; administration & dosage ; pharmacology ; Antineoplastic Combined Chemotherapy Protocols ; adverse effects ; therapeutic use ; Arrhythmias, Cardiac ; chemically induced ; Benzimidazoles ; administration & dosage ; pharmacology ; Breast Neoplasms ; drug therapy ; surgery ; Carbazoles ; administration & dosage ; pharmacology ; Chemotherapy, Adjuvant ; Cyclophosphamide ; adverse effects ; therapeutic use ; Electrocardiography ; drug effects ; Epirubicin ; adverse effects ; therapeutic use ; Female ; Fluorouracil ; adverse effects ; therapeutic use ; Humans ; Mastectomy, Radical ; Middle Aged ; Propanolamines ; administration & dosage ; pharmacology ; Stroke Volume ; drug effects ; Tetrazoles ; administration & dosage ; pharmacology ; Troponin ; metabolism

BACKGROUNDThe loss of cardiac myocytes is one of the mechanisms involved in acute myocardial infarction (AMI)-related heart failure. Autophagy is a common biological process in eukaryote cells. The relationship between cardiac myocyte loss and autophagy after AMI is still unclear. Carvedilol, a non-selective alpha1- and beta-receptor blocker, also suppresses cardiac myocyte necrosis and apoptosis induced by ischemia. However, the association between the therapeutic effects of carvedilol and autophagy is still not well understood. The aim of the present study was to establish a rat model of AMI and observe changes in autophagy in different zones of the myocardium and the effects of carvedilol on autophagy in AMI rats.

METHODSThe animals were randomly assigned to a sham group, an AMI group, a chloroquine intervention group and a carvedilol group. The AMI rat model was established by ligating the left anterior descending coronary artery. The hearts were harvested at 40 minutes, 2 hours, 24 hours and 2 weeks after ligation in the AMI group, at 40 minutes in the chloroquine intervention group and at 2 weeks in other groups. Presence of autophagic vacuoles (AV) in the myocytes was observed by electron microscopy. The expression of autophagy-, anti-apoptotic- and apoptotic-related proteins, MAPLC-3, Beclin-1, Bcl-xl and Bax, were detected by immunohistochemical staining and Western blotting.

RESULTSAVs were not observed in necrotic regions of the myocardium 40 minutes after ligation of the coronary artery. A large number of AVs were found in the region bordering the infarction. Compared with the infarction region and the normal region, the formation of AV was significantly increased in the region bordering the infarction (P < 0.05). The expression of autophagy- and anti-apoptotic-related proteins was significantly increased in the region bordering the infarction. Meanwhile, the expression of apoptotic-related proteins was significantly increased in the infarction region. In the chloroquine intervention group, a large number of initiated AVs (AVis) were found in the necrotic myocardial region. At 2 weeks after AMI, AVs were frequently observed in myocardial cells in the AMI group, the carvedilol group and the sham group, and the number of AVs was significantly increased in the carvedilol group compared with both the AMI group and the sham group (P < 0.05). The expression of autophagy- and anti-apoptotic-related proteins was significantly increased in the carvedilol group compared with that in the AMI group, and the positive expression located in the infarction region and the region bordering the infarction.

CONCLUSIONSAMI induces the formation of AV in the myocardium. The expression of anti-apoptosis-related proteins increases in response to upregulation of autophagy. Carvedilol increases the formation of AVs and upregulates autophagy and anti-apoptosis of the cardiac myocytes after AMI.

Adrenergic beta-Antagonists ; pharmacology ; Animals ; Apoptosis ; Apoptosis Regulatory Proteins ; analysis ; Autophagy ; drug effects ; Beclin-1 ; Carbazoles ; pharmacology ; therapeutic use ; Immunohistochemistry ; Male ; Microscopy, Electron, Transmission ; Myocardial Infarction ; drug therapy ; pathology ; Myocardium ; ultrastructure ; Propanolamines ; pharmacology ; therapeutic use ; Rats ; Rats, Wistar ; Vacuoles ; drug effects

OBJECTIVETo study the clinical effect and mechanism of action of esmolol in the treatment of severe hand, foot, and mouth disease (HFMD).

METHODSA prospective randomized controlled trial was performed. A total of 102 children with severe HFMD were enrolled in the study and were randomly divided into conventional treatment and esmolol treatment groups (n=51 each). The children in the conventional treatment group were given conventional treatment according to the guidelines for the diagnosis and treatment of HFMD. Those in the esmolol treatment group were given esmolol in addition to the conventional treatment. The heart rate (HR), systolic blood pressure (SBP), and respiratory rate (RR) were continuously monitored for all children. Blood samples were collected from all children before treatment and 1, 3, and 5 days after treatment to measure the levels of norepinephrine (NE), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and nuclear factor-kappa B (NF-κB) p65 in mononuclear cells. Serum levels of myocardial enzymes and N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured before treatment and after 5 days of treatment.

RESULTSThere were no significant differences in HR, SBP, RR, NE, TNF-α, IL-6, NF-κB p65, serum myocardial enzymes, and NT-proBNP before treatment between the conventional treatment and esmolol treatment groups. Both groups had significant reductions in these parameters at each time point (P<0.05). Compared with the conventional treatment group, the esmolol treatment group had significant improvements in the above parameters after 1 and 3 days of treatment (P<0.05). After 5 days of treatment, the esmolol treatment group had significant improvements in serum levels of myocardial enzymes and NT-proBNP compared with the conventional treatment group (P<0.05).

CONCLUSIONSEarly application of esmolol can effectively stabilize the vital signs of the children with severe HFMD. Its mechanism of action may be related to reducing serum catecholamine concentration, alleviating myocardial damage, improving cardiac function, and reducing inflammatory response.

Adrenergic beta-1 Receptor Antagonists ; therapeutic use ; Child, Preschool ; Female ; Hand, Foot and Mouth Disease ; blood ; drug therapy ; physiopathology ; Humans ; Infant ; Interleukin-6 ; blood ; Male ; Natriuretic Peptide, Brain ; blood ; Peptide Fragments ; blood ; Propanolamines ; pharmacology ; therapeutic use ; Prospective Studies ; Tumor Necrosis Factor-alpha ; blood