sr-59230a has been researched along with Disease-Models--Animal* in 13 studies
13 other study(ies) available for sr-59230a and Disease-Models--Animal
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Therapeutic candidates for the Zika virus identified by a high-throughput screen for Zika protease inhibitors.
When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection. Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection | 2020 |
Effect of Beta 3 Adrenoreceptor Modulation on Patency of the Ductus Arteriosus.
β3-adrenoreceptor (β3-AR), a G-protein coupled receptor, has peculiar regulatory properties in response to oxygen and widespread localization. β3-AR is expressed in the most frequent neoplasms, also occurring in pregnant women, and its blockade reduces tumor growth, indicating β3-AR-blockers as a promising alternative to antineoplastic drugs during pregnancy. However, β3-AR involvement in prenatal morphogenesis and the consequences of its blockade for the fetus remain unknown. In this study, after the demonstrated expression of β3-AR in endothelial and smooth muscle cells of ductus arteriosus (DA), C57BL/6 pregnant mice were acutely treated at 18.5 of gestational day (GD) with indomethacin or with the selective β3-AR antagonist SR59230A, or chronically exposed to SR59230A from 15.5 to 18.5 GD. Six hours after the last treatment, fetuses were collected. Furthermore, newborn mice were treated straight after birth with BRL37344, a β3-AR agonist, and sacrificed after 7 h. SR59230A, at the doses demonstrated effective in reducing cancer progression (10 and 20 mg/kg) in acute and chronic mode, did not induce fetal DA constriction and did not impair the DA ability to close after birth, whereas at the highest dose (40 mg/kg), it was shown to cause DA constriction and preterm-delivery. BRL37344 administered immediately after birth did not alter the physiological DA closure. Topics: Adrenergic beta-3 Receptor Antagonists; Animals; Animals, Newborn; Disease Models, Animal; Disease Progression; Ductus Arteriosus; Ductus Arteriosus, Patent; Ethanolamines; Female; Indomethacin; Male; Maternal Exposure; Mice; Mice, Inbred C57BL; Pregnancy; Pregnancy, Animal; Propanolamines; Receptors, Adrenergic, beta-3; Receptors, G-Protein-Coupled; Time Factors | 2020 |
Discrete β-adrenergic mechanisms regulate early and late erythropoiesis in erythropoietin-resistant anemia.
Anemia of critical illness is resistant to exogenous erythropoietin. Packed red blood cells transfusions is the only treatment option, and despite related cost and morbidity, there is a need for alternate strategies. Erythrocyte development can be divided into erythropoietin-dependent and erythropoietin-independent stages. We have shown previously that erythropoietin-dependent development is intact in burn patients and the erythropoietin-independent early commitment stage, which is regulated by β1/β2-adrenergic mechanisms, is compromised. Utilizing the scald burn injury model, we studied erythropoietin-independent late maturation stages and the effect of β1/β2, β-2, or β-3 blockade in burn mediated erythropoietin-resistant anemia.. Burn mice were randomized to receive daily injections of propranolol (nonselective β1/β2 antagonist), nadolol (long-acting β1/β2 antagonist), butoxamine (selective β2 antagonist), or SR59230A (selective β3 antagonist) for 6 days after burn. Total bone marrow cells were characterized as nonerythroid cells, early and late erythroblasts, nucleated orthochromatic erythroblasts and enucleated reticulocyte subsets using CD71, Ter119, and Syto-16 by flow cytometry. Multipotential progenitors were probed for MafB expressing cells.. Although propranolol improved early and late erythroblasts, only butoxamine and selective β3-antagonist administrations were positively reflected in the peripheral blood hemoglobin and red blood cells count. While burn impeded early commitment and late maturation stages, β1/β2 antagonism increased the early erythroblasts through commitment stages via β2 specific MafB regulation. β3 antagonism was more effective in improving overall red blood cells through late maturation stages.. The study unfolds novel β2 and β3 adrenergic mechanisms orchestrating erythropoietin resistant anemia after burn, which impedes both the early commitment stage and the late maturation stages, respectively. Topics: Adrenergic Antagonists; Anemia; Animals; Burns; Butoxamine; Disease Models, Animal; Erythropoiesis; Male; Mice; Nadolol; Propanolamines; Propranolol; Receptors, Adrenergic, beta | 2017 |
Functional involvement of β3-adrenergic receptors in melanoma growth and vascularization.
β-adrenergic signaling is thought to facilitate cancer progression and blockade of β-adrenergic receptors (β-ARs) may slow down tumor growth. A possible role of β3-ARs in tumor growth has not been investigated so far and the lack of highly specific antagonists makes difficult the evaluation of this role. In the present study, β3-AR expression in mouse B16F10 melanoma cells was demonstrated and the effects of two widely used β3-AR blockers, SR59230A and L-748,337, were evaluated in comparison with propranolol, a β1-/β2-AR blocker with poor affinity for β3-ARs, and with siRNAs targeting specific β-ARs. Both SR59230A and L-748,337 reduced cell proliferation and induced apoptosis, likely through the involvement of the inducible isoform of nitric oxide synthase. In addition, hypoxia upregulated β3-ARs and vascular endothelial growth factor (VEGF) in B16F10 cells, whereas SR59230A or L-748,337 prevented the hypoxia-induced VEGF upregulation. Melanoma was induced in mice by inoculation of B16F10 cells. Intra-tumor injections of SR59230A or L-748,337 significantly reduced melanoma growth by reducing cell proliferation and stimulating apoptosis. SR59230A or L-748,337 treatment also resulted in significant decrease of the tumor vasculature. The decrease in tumor vasculature was due to apoptosis of endothelial cells and not to downregulation of angiogenic factors. These results demonstrate that SR59230A and L-748,337 significantly inhibit melanoma growth by reducing tumor cell proliferation and activating tumor cell death. In addition, both drugs reduce tumor vascularization by inducing apoptosis of endothelial cells. Together, these findings indicate β3-ARs as promising, novel targets for anti-cancer therapy.. β3-ARs are expressed in B16F10 melanoma cells β3-ARs are involved in B16F10 cell proliferation and apoptosis Reduced β3-AR function decreases the growth of melanoma induced by B16F10 cell inoculation Drugs targeting β3-ARs reduce tumor vasculature β3-ARs can be regarded as promising, novel targets for anti-cancer therapy. Topics: Adrenergic beta-3 Receptor Antagonists; Animals; Apoptosis; Cell Hypoxia; Cell Proliferation; Disease Models, Animal; Gene Expression Regulation, Neoplastic; Gene Silencing; Male; Melanoma; Melanoma, Experimental; Mice; Neovascularization, Pathologic; Propanolamines; Receptors, Adrenergic, beta-3; RNA Interference; Tumor Burden; Vascular Endothelial Growth Factor A | 2013 |
β3-adrenoceptor mediates metabolic protein remodeling in a rabbit model of tachypacing-induced atrial fibrillation.
The beta 3-adrenoceptor (β3-AR) is closely associated with energy metabolism. This study aimed to explore the role of β3-AR in energy remodeling in a rabbit model of pacing-induced atrial fibrillation (AF).. Rabbits with a sham-operation or pacing-induced AF were used for this study, and the latter group was further divided into three subgroups: 1) the pacing group, 2) the β3-AR agonist (BRL37344)-treated group, and 3) the β3-AR antagonist (SR59230A)-treated group. Atrial electrogram morphology and surface ECG were used to monitor the induction of AF and atrial effective refractory period (AERP). RT-PCR and western blot (WB) were used to show alterations in β3-AR and metabolic-related protein.. RT-PCR and WB results showed that β3-AR was significantly upregulated in the pacing group, and that it corresponded with high AF inducibility and significantly decreased AERP200 and ATP production in this group. Inhibition of β3-AR decreased the AF induction rate, reversed AERP200 reduction, and restored ATP levels in the AF rabbits. Further activation of β3-AR using agonist BRL37344 exacerbated AF-induced metabolic disruption. Periodic acid Schiff (PAS) and Oil Red O staining showed β3-AR-dependent glycogen and lipid droplet accumulation in cardiac myocytes with AF. Glucose transporter-4 (GLUT-4) and CD36, key transporters of glucose and fatty acids, were downregulated in the pacing group. Expression of carnitine-palmitoyltransferase I (CPT-1), a key regulator in fatty acid metabolism, was also significantly downregulated in the pacing group. Reduced glucose transportation and fatty acid oxidation could be restored by inhibition of β3-AR. Furthermore, key regulators of metabolism, peroxisome proliferator-activated receptor-α (PPARα) and PPAR co-activator (PGC-1α) can be regulated by pharmacological intervention of the β3-AR.. β3-AR is involved in metabolic protein remodeling in AF. PPARα/PGC-1α signaling pathway might be the relevant down-stream molecular machinery in response to AF-induced activation of β3-AR. β3-AR might be a novel target in AF treatment. Topics: Adenosine Triphosphate; Adrenergic beta-3 Receptor Agonists; Adrenergic beta-3 Receptor Antagonists; Animals; Atrial Fibrillation; Cardiac Pacing, Artificial; CD36 Antigens; Disease Models, Animal; Down-Regulation; Electrocardiography; Fatty Acids; Glucose Transporter Type 4; Myocytes, Cardiac; PPAR alpha; Propanolamines; Rabbits; Receptors, Adrenergic, beta-3; Signal Transduction; Transcription Factors; Up-Regulation | 2013 |
Two-week treatment with the β₃-adrenoceptor antagonist SR59230A normalizes the increased pancreatic islet blood flow in type 2 diabetic GK rats.
The Goto-Kakizaki (GK) rat, a type 2 diabetes model, has increased pancreatic islet and white adipose tissue (WAT) blood flow, and this can be normalized by acute administration of SR59230A, a β₃ -adrenoceptor antagonist. We now implanted osmotic pumps which allowed a constant release of saline or SR59230A (0.6 mg/kg × day) for 2 weeks. A decrease in islet blood flow was seen also after 2 weeks of continuous SR59230A treatment in the GK rat. However, no improvement in glucose tolerance was seen in the GK rats. Neither did SR59230A affect insulin secretion from isolated islets in vitro. WAT blood flow was not affected by the 2-week SR59230A treatment. Thus, the increased islet blood flow seen in the GK rat can be normalized for up to 2 weeks, which opens the possibilities for further studies on the long-term functional role on the islet blood flow increase in this type 2 diabetes model. Topics: Adrenergic beta-3 Receptor Antagonists; Animals; Blood Glucose; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Disease Models, Animal; Glucose Tolerance Test; Islets of Langerhans; Propanolamines; Rats; Rats, Inbred Strains; Regional Blood Flow | 2012 |
Does selective beta-1 blockade provide bone marrow protection after trauma/hemorrhagic shock?
Previously, nonselective beta-blockade (BB) with propranolol demonstrated protection of the bone marrow (BM) after trauma and hemorrhagic shock (HS). Because selective beta-1 blockers are used commonly for their cardiac protection, the aim of this study was to more clearly define the role of specific beta adrenergic receptors in BM protection after trauma and HS.. Male Sprague-Dawley rats underwent unilateral lung contusion (LC) followed by HS for 45 minutes. After resuscitation, animals were injected with a selective beta-blocker, atenolol (B1B), butoxamine (B2B), or SR59230A (B3B). Animals were killed at 3 hours or 7 days. Heart rate and blood pressure were measured throughout the study period. BM cellularity, growth of hematopoietic progenitor cells (HPCs) in BM, and hemoglobin levels (Hb) were assessed.. Treatment with a B2B or B3B after LCHS restored both BM cellularity and BM HPC colony growth at 3 hours and 7 days. In contrast, treatment with a B1B had no effect on BM cellularity or HPC growth but did decrease heart effectively rate throughout the study. Treatment with a B3B after LCHS increased Hb as compared with LCHS alone.. After trauma and HS, protection of BM for 7 days was seen with use of either a selective beta-2 or beta-3 blocker. Use of a selective beta-1 blocker was ineffective in protecting the BM despite a physiologic decrease in heart rate. Therefore, the protection of BM is via the beta-2 and beta-3 receptors and it is not via a direct cardiovascular effect. Topics: Adrenergic beta-Antagonists; Animals; Atenolol; Bone Marrow; Butoxamine; Contusions; Disease Models, Animal; Hematopoietic Stem Cells; Lung Injury; Male; Propanolamines; Protective Agents; Rats; Rats, Sprague-Dawley; Shock, Hemorrhagic | 2012 |
Social defeat stress induces hyperthermia through activation of thermoregulatory sympathetic premotor neurons in the medullary raphe region.
Psychological stress-induced hyperthermia is a fundamental autonomic response in mammals. However, the central circuitry underlying this stress response is poorly understood. Here, we sought to identify sympathetic premotor neurons that mediate a hyperthermic response to social defeat stress, a psychological stress model. Intruder rats that were defeated by a dominant resident conspecific exhibited a rapid increase in abdominal temperature by up to 2.0 °C. In these defeated rats, we found that expression of Fos, a marker of neuronal activation, was increased in the rostral medullary raphe region centered in the rostral raphe pallidus and adjacent raphe magnus nuclei. In this region, Fos expression was observed in a large population of neurons expressing vesicular glutamate transporter 3 (VGLUT3), which are known as sympathetic premotor neurons controlling non-shivering thermogenesis in brown adipose tissue (BAT) and thermoregulatory constriction of skin blood vessels, and also in a small population of tryptophan hydroxylase-positive serotonergic neurons. Intraperitoneal injection of diazepam, an anxiolytic agent, but not indomethacin, an antipyretic, significantly reduced both the stress-induced hyperthermia and Fos expression in these medullary raphe neuronal populations. Systemic blockade of β3 -adrenoreceptors, which are abundantly expressed in BAT, also attenuated the stress-induced hyperthermia. These results suggest that psychological stress signals activate VGLUT3-expressing medullary raphe sympathetic premotor neurons, which then drive hyperthermic effector responses including BAT thermogenesis through β(3) -adrenoreceptors. Topics: Adrenergic beta-3 Receptor Antagonists; Analysis of Variance; Animals; Anti-Anxiety Agents; Body Temperature Regulation; Cell Count; Cyclooxygenase Inhibitors; Diazepam; Disease Models, Animal; Dominance-Subordination; Hypothermia; Indomethacin; Lipopolysaccharides; Male; Neurons; Oncogene Proteins v-fos; Propanolamines; Raphe Nuclei; Rats; Rats, Long-Evans; Rats, Wistar; Stress, Psychological; Tryptophan Hydroxylase; Vesicular Glutamate Transport Proteins | 2011 |
Antiangiogenic effects of β2 -adrenergic receptor blockade in a mouse model of oxygen-induced retinopathy.
Oxygen-induced retinopathy (OIR) is a model for human retinopathy of prematurity. In mice with OIR, beta-adrenergic receptor (β-AR) blockade with propranolol has been shown to ameliorate different aspects of retinal dysfunction in response to hypoxia. In the present study, we used the OIR model to investigate the role of distinct β-ARs on retinal proangiogenic factors, pathogenic neovascularization and electroretinographic responses. Our results demonstrate that β(2) -AR blockade with ICI 118,551 decreases retinal levels of proangiogenic factors and reduces pathogenic neovascularization, whereas β(1) - and β(3) -AR antagonists do not. Determination of retinal protein kinase A activity is indicative of the fact that β-AR blockers are indeed effective at the receptor level. In addition, the specificity of ICI 118,551 on retinal angiogenesis has been demonstrated by the finding that in mouse retinal explants, β(2) -AR silencing prevents ICI 118,551 effects on hypoxia-induced vascular endothelial growth factor accumulation. In OIR mice, ICI 118,551 is effective in increasing electroretinographic responses suggesting that activation of β(2) -ARs constitutes an important part of the retinal response to hypoxia. Lastly, immunohistochemical studies demonstrate that β(2) -ARs are localized to several retinal cells, particularly to Müller cells suggesting the possibility that β(2) -ARs play a role in regulating vascular endothelial growth factor production by these cells. The present results suggest that pathogenic angiogenesis, a key change in many hypoxic/ischemic vision-threatening retinal diseases, depends at least in part on β(2) -AR activity and indicate that β(2) -AR blockade can be effective against retinal angiogenesis. Topics: Adrenergic beta-2 Receptor Antagonists; Adrenergic beta-Antagonists; Angiogenesis Inhibitors; Animals; Animals, Newborn; Atenolol; Cyclic AMP-Dependent Protein Kinases; Disease Models, Animal; Dose-Response Relationship, Drug; Electroretinography; Enzyme-Linked Immunosorbent Assay; Female; Gene Expression Regulation, Developmental; Humans; Infant, Newborn; Insulin-Like Growth Factor I; Male; Mice; Mice, Inbred C57BL; Organ Culture Techniques; Oxygen; Platelet Endothelial Cell Adhesion Molecule-1; Propanolamines; Receptors, Adrenergic, beta-2; Retinal Neovascularization; Retinopathy of Prematurity; RNA, Messenger; RNA, Small Interfering; Statistics, Nonparametric; Transfection; Vascular Endothelial Growth Factor A | 2011 |
Use of fat-fed rats to study the metabolic and vascular sequelae of obesity and beta-adrenergic antagonism.
Obesity-associated cardiovascular disease exerts profound human and monetary costs, creating a mounting need for cost-effective and relevant in vivo models of the complex metabolic and vascular interrelationships of obesity. Obesity is associated with endothelial dysfunction and inflammation. Free fatty acids (FFA), generated partly through beta-adrenergic receptor-mediated lipolysis, may impair endothelium-dependent vasodilation (EDV) by proinflammatory mechanisms. beta-Adrenergic antagonists protect against cardiovascular events by mechanisms not fully defined. We hypothesized that beta antagonists may exert beneficial effects, in part, by inhibiting lipolysis and reducing FFA. Further, we sought to evaluate the fat-fed rat as an in vivo model of obesity-induced inflammation and EDV. Control and fat-fed rats were given vehicle or beta antagonist for 28 d. Serum FFA were measured to determine the association to serum IL6, TNFalpha, and C-reactive protein and to femoral artery EDV. Compared with controls, fat-fed rats weighed more and had higher FFA, triglyceride, leptin, and insulin levels. Unexpectedly, in control and fat-fed rats, beta antagonism increased FFA, yet inflammatory cytokines were reduced and EDV was preserved. Therefore, reduction of FFA is unlikely to be the mechanism by which beta antagonists protect the endothelium. These results reflect the need for validation of ex vivo models of obesity-induced inflammation and endothelial dysfunction, concurrent with careful control of dietary fat composition and treatment duration. Topics: Acetylcholine; Adrenergic beta-Antagonists; Animals; Blood Flow Velocity; Body Weight; Cytokines; Dietary Fats; Disease Models, Animal; Endothelium, Vascular; Inflammation; Male; Obesity; Propanolamines; Propranolol; Rats; Rats, Sprague-Dawley; Receptors, Adrenergic, beta; Vasodilation | 2009 |
Behavioral effects of the beta3 adrenoceptor agonist SR58611A: is it the putative prototype of a new class of antidepressant/anxiolytic drugs?
A large body of evidence corroborates the notion that deficiencies of serotonergic system are likely involved in the pathogenesis of both depression and anxiety. Activation of beta(3) adrenoceptors has been shown to increase brain tryptophan content suggesting an elevation of brain serotonin (5HT) synthesis. SR58611A is a selective beta(3) adrenergic agent possessing a profile of antidepressant activity in routine rodents' experimental models of depression. The present study was undertaken to evaluate in rodents the antidepressant properties of SR58611A and to assess its putative anxiolytic value in experimental models of depression and anxiety. Compared to the control group, SR58611A (0.1, 1, 5 or 10 mg/kg) caused a dose-dependent reduction in immobility of Wistar male rats in the forced swim test. The maximum dose appeared to be equivalent to an effective dose of clomipramine (50 mg/kg). In addition, acute injection of SR58611A induced in rats a dose-dependent decrease in grooming response to a novel environment (novelty-induced grooming test). For any dose, the effect was lower than that of diazepam (1 mg/kg). Chronic treatment with SR58611A resulted also in an increased social interaction time in the social interaction test without affecting motor activity of rats. Furthermore, similarly to diazepam a chronic treatment with the highest doses of SR58611A was followed by increased exploratory behavior in Swiss male mice exposed to the elevated plus maze test. These effects are mediated by beta(3) adrenoceptors since i.p. pretreatment with the selective beta(3) adrenoceptor antagonist SR59230A (5 mg/kg) blocked the effects of SR58611A. Finally, also the 5HT antagonist methysergide (2 mg/kg) prevented the antidepressant and anxiolytic-like activity of SR58611A indicating that 5HT transmission is strictly involved in its action. Topics: Adrenergic beta-3 Receptor Agonists; Adrenergic beta-3 Receptor Antagonists; Adrenergic beta-Antagonists; Analysis of Variance; Animals; Anti-Anxiety Agents; Antidepressive Agents; Anxiety; Behavior, Animal; Clomipramine; Depression; Disease Models, Animal; Dose-Response Relationship, Drug; Grooming; Injections, Intraperitoneal; Male; Maze Learning; Methysergide; Mice; Motor Activity; Propanolamines; Rats; Rats, Wistar; Receptors, Adrenergic, beta-3; Serotonin Antagonists; Swimming; Tetrahydronaphthalenes | 2007 |
[Effect of beta3-adrenoceptor antagonist on the cardiac function and expression of endothelial nitric oxide synthase in a rat model of heart failure].
To investigate the effect of beta(3)-adrenoceptor (beta(3)-AR) antagonist (SR59230A) on the cardiac function and left ventricular remodeling in a rat model of heart failure induced by isoproterenol (ISO), and to probe into its mechanism.. Eight rats were randomly selected to serve as controls from 85 male adult Wistar rats. After a heart failure model was reproduced, twenty remain rats were randomly divided into ISO group (n = 10) and SR59230A group (SR group, n = 10). ISO group received intraperitoneal injection of 1 ml saline twice a day; SR group received intraperitoneal injection of 85 nmol SR59230A in 1 ml saline twice a day; control group received no treatment. The parameters determined included echocardiogram, the expression of nitric oxide synthase (eNOS) of left ventricle by the technique of reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting, cyclic guanosine monophosphate (cGMP) level by enzyme linked immunosorbent assay (ELISA), the ratio of left ventricular weight and body weight (LVW/BW), and the ratio of lung weight and body weight (PW/BW).. Compared with control group, the left ventricular end systolic pressure (LVESP), the maximum and minimum first derivative of left ventricular pressure (+/-dp/dtmax) were significantly decreased (all P<0.01), while heart rate (HR) and left ventricular end-diastolic pressure (LVEDP) were significantly increased (both P<0.01) in ISO group. Compared with ISO group, LVESP, +/-dp/dtmax were markedly higher (P<0.05 or P<0.01) respectively, whereas HR and LVEDP were markedly lower (P<0.05 and P<0.01) in SR group, and there was no difference in HR between SR group and control group (P>0.05), while LVEDP was higher in RS group than control group (P<0.01). The levels of eNOS mRNA, protein and cGMP were significantly lower in SR group compared with ISO group (all P<0.01). In addition, when compared with ISO group, LVW/BW ratio and PW/BW ratio in SR group were also decreased (both P<0.05).. beta(3)-AR antagonist SR59230A can block the beta(3)-AR-NOS-cGMP pathway and improve cardiac function in heart failure in rat when if is administered for a long term. SR59230A can also improve left ventricular remodeling in a certain degree. Topics: Adrenergic beta-3 Receptor Antagonists; Animals; Disease Models, Animal; Heart Failure; Male; Nitric Oxide Synthase Type III; Propanolamines; Random Allocation; Rats; Rats, Wistar; RNA, Messenger; Ventricular Function, Left; Ventricular Remodeling | 2007 |
Chronic blocking of beta 3-adrenoceptor ameliorates cardiac function in rat model of heart failure.
Stimulation 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.. Male 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.. The 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).. Chronic 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. Topics: Adrenergic beta-3 Receptor Antagonists; Adrenergic beta-Antagonists; Animals; Blotting, Western; Disease Models, Animal; Echocardiography; Enzyme-Linked Immunosorbent Assay; Heart Failure; Male; Myocardium; Nitric Oxide Synthase Type III; Propanolamines; Rats; Rats, Wistar; Receptors, Adrenergic, beta-3; Reverse Transcriptase Polymerase Chain Reaction; Ventricular Function, Left | 2007 |