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1.
Arq. bras. cardiol ; 112(3): 304-308, Mar. 2019. tab, graf
Article in English | LILACS | ID: biblio-1038536

ABSTRACT

Abstract The effect of third and second-generation type of beta-blocker on substrate oxidation especially during high-intensity exercises are scarce. The objective of the study is to explore differences of beta-blocker regimens (vasodilating vs. non-vasodilating beta-blockers) for substrate oxidation during in high-intensity intermittent exercise (HIIE) in chronic heart failure and reduced ejection fraction (HFrEF). Eighteen CHF males (58.8 ± 9 years), 8 under use of β1 specific beta-blockers+alfa 1-blocker and 10 using β1 non-specific beta-blockers, were randomly assigned to 4 different HIIE, in a cross-over design. The 4 protocols were: 30 seconds (A and B) or 90 seconds (C and D) at 100% peak power output, with passive (A and C) or active recovery (50% of PPO; B and D). Energy expenditure (EE; kcal/min), quantitative carbohydrate (CHO) and lipid oxidation (g/min) and qualitative (%) contribution were calculated. Two-way ANOVA and Bonferroni post-hoc test were used (p-value ≤ 0.05) to compare CHO and lipid oxidation at rest and at 10min. Total exercise time or EE did not show differences for beta-blocker use. The type of beta-blocker use showed impact in CHO (%) and lipid (g/min and %) for rest and 10 min, but absolute contribution of CHO (g/min) was different just at 10min (Interaction p = 0.029). Higher CHO oxidation was found in vasodilating beta-blockers when comparing to non-vasodilating. According to our pilot data, there is an effect of beta-blocker type on substrate oxidation during HIIE, but no influence on EE or exercise total time in HFrEF patients.


Resumo Os dados sobre efeito do tipo de betabloqueador de terceira e segunda geração na oxidação do substrato, especialmente durante exercícios de alta intensidade, são escassos. O objetivo do estudo é explorar as diferenças de tratamentos com betabloqueadores (betabloqueadores vasodilatadores vs. não-vasodilatadores) na oxidação de substratos durante exercícios intermitentes de alta intensidade (HIIE) na insuficiência cardíaca crônica e fração de ejeção do ventrículo esquerdo reduzida (ICFEr). Dezoito pacientes do sexo masculino com ICC (58,8 ± 9 anos), 8 em uso de betabloqueadores β1 específicos + bloqueador α-1 e 10 utilizando betabloqueadores β1 não-específicos, foram aleatoriamente designados para 4 diferentes HIIE, em um desenho cruzado. Os 4 protocolos foram: 30 segundos (A e B) ou 90 segundos (C e D) a 100% da potência de pico de saída (PPO), com recuperação passiva (A e C) ou ativa (50% de PPO; B e D). O gasto energético (GE; kcal/min), a ingestão de carboidratos quantitativos (CHO) e oxidação lipídica (g/min) e qualitativa (%) foram calculados. Anova de dois fatores e teste post-hoc de Bonferroni foram usados (p-valor ≤ 0,05) para comparar a oxidação de CHO e lipídios em repouso e aos 10 minutos. O tempo total de exercício ou GE não mostraram diferenças de acordo com o uso de betabloqueadores. O tipo de betabloqueador mostrou impacto em CHO (%) e lípides (g/min e %) para repouso e aos 10 min, mas a contribuição absoluta de CHO (g/min) foi diferente apenas aos 10 minutos (Interação p = 0,029). Foram encontradas maiores oxidações de CHO com betabloqueadores vasodilatadores quando comparados com os não-vasodilatadores. De acordo com nossos dados piloto, há um efeito do tipo do betabloqueador na oxidação do substrato durante o HIIE, mas nenhuma influência no GE ou no tempo total de exercício nos pacientes com ICFEr.


Subject(s)
Humans , Male , Middle Aged , Aged , Exercise/physiology , Adrenergic beta-Agonists/pharmacology , Energy Metabolism/drug effects , Carbohydrate Metabolism/physiology , High-Intensity Interval Training/methods , Heart Failure/physiopathology , Ventricular Function, Left/physiology , Adrenergic beta-Agonists/metabolism , Cross-Over Studies , Lipid Metabolism/physiology , Heart Failure/metabolism
2.
Acta cir. bras ; 34(5): e201900505, 2019. graf
Article in English | LILACS | ID: biblio-1010872

ABSTRACT

Abstract Purpose: To evaluate the cardioprotective response of the pharmacological modulation of β-adrenergic receptors (β-AR) in animal model of cardiac ischemia and reperfusion (CIR), in spontaneously hypertensive (SHR) and normotensive (NWR) rats. Methods: CIR was induced by the occlusion of left anterior descendent coronary artery (10 min) and reperfusion (75 min). The SHR was treated with β-AR antagonist atenolol (AT, 10 mg/kg, IV) 5 min before CIR, and NWR were treated with β-AR agonist isoproterenol (ISO, 0.5 mg/kg, IV) 5 min before CIR. Results: The treatment with AT increased the incidence of VA, AVB and LET in SHR, suggesting that spontaneous cardioprotection in hypertensive animals was abolished by blockade of β-AR. In contrast, the treatment with ISO significantly reduced the incidence of ventricular arrhythmia, atrioventricular blockade and lethality in NWR (30%, 20% and 20%, respectively), suggesting that the activation of β-AR stimulate cardioprotection in normotensive animals. Serum CK-MB were higher in SHR/CIR and NWR/CIR compared to respective SHAM group (not altered by treatment with AT or ISO). Conclusion: The pharmacological modulation of β-AR could be a new cardioprotective strategy for the therapy of myocardial dysfunctions induced by CIR related to cardiac surgery and cardiovascular diseases.


Subject(s)
Animals , Male , Atenolol/pharmacology , Cardiotonic Agents/pharmacology , Myocardial Reperfusion Injury/drug therapy , Receptors, Adrenergic, beta/drug effects , Adrenergic beta-Agonists/pharmacology , Adrenergic beta-1 Receptor Antagonists/pharmacology , Isoproterenol/pharmacology , Rats, Inbred SHR , Time Factors , Blood Pressure/drug effects , Biomarkers/blood , Myocardial Reperfusion Injury/physiopathology , Myocardial Reperfusion Injury/blood , Reproducibility of Results , Treatment Outcome , Creatine Kinase, MB Form/blood , Heart Function Tests
3.
Yonsei Medical Journal ; : 557-564, 2016.
Article in English | WPRIM | ID: wpr-52546

ABSTRACT

PURPOSE: Periostin mediates critical steps in gastric cancer and is involved in various signaling pathways. However, the roles of periostin in promoting gastric cancer metastasis are not clear. The aim of this study was to investigate the relevance between periostin expression and gastric cancer progression and the role of stress-related hormones in the regulation of cancer development and progression. MATERIALS AND METHODS: Normal, cancerous and metastatic gastric tissues were collected from patients diagnosed with advanced gastric cancer. The in vivo expression of periostin was evaluated by in situ hybridization and immunofluorescent staining. Meanwhile, human gastric adenocarcinoma cell lines MKN-45 and BGC-803 were used to detect the in vitro expression of periostin by using quantitative real-time polymerase chain reaction (PCR) and western blotting. RESULTS: Periostin is expressed in the stroma of the primary gastric tumors and metastases, but not in normal gastric tissue. In addition, we observed that periostin is located mainly in pericryptal fibroblasts, but not in the tumor cells, and strongly correlated to the expression of α-smooth muscle actin (SMA). Furthermore, the distribution patterns of periostin were broader as the clinical staging of tumors progressed. We also identified a role of stress-related signaling in promoting cancer development and progression, and found that isoprenaline upregulated expression levels of periostin in gastric cancer cells. CONCLUSION: These findings suggest that the distribution pattern of periostin was broader as the clinical staging of the tumor progressed and found that isoprenaline upregulated expression levels of periostin in gastric cancer cells.


Subject(s)
Adenocarcinoma/metabolism , Adrenergic beta-Agonists/pharmacology , Aged , Blotting, Western , Cell Adhesion Molecules/drug effects , Cell Line, Tumor , Fibroblasts/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Humans , Isoproterenol/pharmacology , Male , Neoplasm Staging , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Signal Transduction , Stomach/metabolism , Stomach Neoplasms/metabolism , Up-Regulation
5.
Acta cir. bras ; 29(11): 703-710, 11/2014. tab, graf
Article in English | LILACS | ID: lil-728647

ABSTRACT

PURPOSE: To verify the effects of different catecholamines on volemic expansion and on the autonomic nervous system in rabbits that were subjected to hemorrhage. METHODS: Twenty four rabbits subjected to hemorrhage (with a 25% loss of blood volume) and were randomly divided into four experimental groups: 1) HEMO Group underwent replacement with their own blood in an equal volume; 2) SS Group underwent replacement with saline solution (SS) in a volume that corresponded to three times the removed blood volume; 3) ISP Group underwent replacement with SS and isoprenaline; 4) FNL Group underwent replacement with SS and phenylephrine. Spectral Analysis of the heart rate and heart rate variability were performed from the recorded data. Hematocrit was measured throughout the experiment. RESULTS: Replacement with SS and an α- or β-agonist did not produce differences in the intravascular retention compared to replacement with SS alone. An analysis of HRV showed that the FNL group maintained the LF/HF ratio better than ISP and SS. CONCLUSIONS: No difference in vascular retention when α- or β- agonists were added to SS during post-hemorrhagic recovery. The animals in the FNL group maintained the integrity of the autonomic response within normal physiological standards during hemorrhagic stress. .


Subject(s)
Animals , Rabbits , Blood Volume/drug effects , Catecholamines/pharmacology , Heart Rate/drug effects , Hemorrhage/physiopathology , Sodium Chloride/pharmacology , Adrenergic alpha-1 Receptor Agonists/pharmacology , Adrenergic beta-Agonists/pharmacology , Autonomic Nervous System/drug effects , Blood Transfusion, Autologous , Fourier Analysis , Hematocrit , Heart Rate/physiology , Hemorrhage/etiology , Hemorrhage/therapy , Isoproterenol/pharmacology , Phenylephrine/pharmacology , Random Allocation , Reference Values , Reproducibility of Results , Spectrum Analysis , Time Factors
6.
Neumol. pediátr ; 5(2): 96-99, 2010. tab
Article in Spanish | LILACS | ID: lil-588442

ABSTRACT

A pesar del uso de corticoides inhalados en el tratamiento del asma bronquial existe un número variable de pacientes que no logran el control de su enfermedad. En estos casos, una de las alternativas terapéuticas propuesta por diversas guías clínicas es la adición de beta 2 agonistas de acción prolongada. Este articulo, revisa las características farmacológicas, posibles efectos adversos y las indicaciones en niños.


Subject(s)
Humans , Child , Anti-Asthmatic Agents/therapeutic use , Bronchodilator Agents/therapeutic use , Adrenergic beta-Agonists/therapeutic use , Asthma/drug therapy , Anti-Asthmatic Agents/adverse effects , Anti-Asthmatic Agents/pharmacology , Bronchodilator Agents/adverse effects , Bronchodilator Agents/pharmacology , Adrenergic beta-Agonists/adverse effects , Adrenergic beta-Agonists/pharmacology , Combined Modality Therapy , Adrenal Cortex Hormones/therapeutic use
7.
Int. braz. j. urol ; 35(1): 76-83, Jan.-Feb. 2009. ilus, graf, tab
Article in English | LILACS | ID: lil-510266

ABSTRACT

Purpose: We investigated the presence of functional ß1, ß2 and ß3-adrenoceptor in urothelium and detrusor muscle of human bladder through in vitro pharmacology of selective ß3 adrenoceptor agonist solabegron. Materials and Methods: Expression of these adrenoceptors in surgically separated human urothelium and detrusor muscle were investigated using RT-PCR. The effects of activating these receptors were studied by determining the relaxation produced by ß-adrenoceptors agonist in pre-contracted human detrusor strips. Results: The results confirmed the presence of mRNA for ß1, ß2 and ß3-adrenoceptor in both human urothelium and detrusor. In an in vitro functional bladder assay, Solabegron and other agonists for ß-adrenoceptors such as procaterol and isoproterenol evoked potent concentration-dependent relaxation of isolated human bladder strips with pD2 values of 8.73 ± 0.19, 5.08 ± 0.48 and 6.28 ± 0.54, respectively. Conclusions: Selective ß3-adrenoceptor agonist may be a potential new treatment for the overactive bladder OAB syndrome. Existence of ß3-adrenoceptor mRNA exists in the urothelium in addition to the detrusor muscle suggest multiple site of actions for the ß3-adrenoceptor in the lower urinary tract.


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Adrenergic beta-Agonists/pharmacology , Aniline Compounds/pharmacology , Benzoates , /agonists , Urinary Bladder/drug effects , Urothelium/drug effects , Dose-Response Relationship, Drug , Muscle, Smooth/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Receptors, Adrenergic, beta-1/agonists , Receptors, Adrenergic, beta-1/genetics , /genetics , /agonists , /genetics , Urinary Bladder/metabolism , Urothelium/metabolism , Young Adult
8.
Article in English | WPRIM | ID: wpr-136587

ABSTRACT

The effects of glucagon and epinephrine on gluconeogenesis in young (4 month) and old (24 month) Fisher 344 rat hepatocytes were compared. In contrast to glucagon, which had a similar effect on gluconeogenesis in both young and old cells, epinephrine caused a smaller increase in gluconeogenesis in old rat hepatocytes than in young hepatocytes. beta2 adrenergic receptor (beta2-AR) expression slightly decreased in aged rat liver, and there were differences between young and old hepatocytes in their patterns of G protein coupled receptor kinases, which are involved in the activation of beta2-AR receptor signal desensitization. The major isoform of the kinase changed from GRK2 to GRK3 and the expression of beta-arrestin, which is recruited by the phosphorylated beta2-AR for internalization and degradation, increased in aged rat liver. GRK3 overexpression also decreased the glucose output from young rat hepatocytes. We conclude that an age-associated reduction in epinephrine-induced gluconeogenesis occurs through the epinephrine receptor desensitizing system.


Subject(s)
Adrenergic beta-Agonists/pharmacology , Aging/drug effects , Animals , Epinephrine/pharmacology , G-Protein-Coupled Receptor Kinase 2/metabolism , G-Protein-Coupled Receptor Kinase 3/metabolism , Glucagon/pharmacology , Gluconeogenesis/drug effects , Male , Models, Biological , Phosphorylation , Rats , Rats, Inbred F344 , Receptors, Adrenergic, beta-2/agonists
9.
Article in English | WPRIM | ID: wpr-136586

ABSTRACT

The effects of glucagon and epinephrine on gluconeogenesis in young (4 month) and old (24 month) Fisher 344 rat hepatocytes were compared. In contrast to glucagon, which had a similar effect on gluconeogenesis in both young and old cells, epinephrine caused a smaller increase in gluconeogenesis in old rat hepatocytes than in young hepatocytes. beta2 adrenergic receptor (beta2-AR) expression slightly decreased in aged rat liver, and there were differences between young and old hepatocytes in their patterns of G protein coupled receptor kinases, which are involved in the activation of beta2-AR receptor signal desensitization. The major isoform of the kinase changed from GRK2 to GRK3 and the expression of beta-arrestin, which is recruited by the phosphorylated beta2-AR for internalization and degradation, increased in aged rat liver. GRK3 overexpression also decreased the glucose output from young rat hepatocytes. We conclude that an age-associated reduction in epinephrine-induced gluconeogenesis occurs through the epinephrine receptor desensitizing system.


Subject(s)
Adrenergic beta-Agonists/pharmacology , Aging/drug effects , Animals , Epinephrine/pharmacology , G-Protein-Coupled Receptor Kinase 2/metabolism , G-Protein-Coupled Receptor Kinase 3/metabolism , Glucagon/pharmacology , Gluconeogenesis/drug effects , Male , Models, Biological , Phosphorylation , Rats , Rats, Inbred F344 , Receptors, Adrenergic, beta-2/agonists
10.
Braz. j. med. biol. res ; 41(12): 1054-1058, Dec. 2008. ilus, tab
Article in English | LILACS | ID: lil-502155

ABSTRACT

The aim of the present study was to evaluate the effect of joint immobilization on morphometric parameters and glycogen content of soleus muscle treated with clenbuterol. Male Wistar (3-4 months old) rats were divided into 4 groups (N = 6 for each group): control, clenbuterol, immobilized, and immobilized treated with clenbuterol. Immobilization was performed with acrylic resin orthoses and 10 µg/kg body weight clenbuterol was administered subcutaneously for 7 days. The following parameters were measured the next day on soleus muscle: weight, glycogen content, cross-sectional area, and connective tissue content. The clenbuterol group showed an increase in glycogen (81.6 percent, 0.38 ± 0.09 vs 0.69 ± 0.06 mg/100 g; P < 0.05) without alteration in weight, cross-sectional area or connective tissue compared with the control group. The immobilized group showed a reduction in muscle weight (34.2 percent, 123.5 ± 5.3 vs 81.3 ± 4.6 mg; P < 0.05), glycogen content (31.6 percent, 0.38 ± 0.09 vs 0.26 ± 0.05 mg/100 mg; P < 0.05) and cross-sectional area (44.1 percent, 2574.9 ± 560.2 vs 1438.1 ± 352.2 µm²; P < 0.05) and an increase in connective tissue (216.5 percent, 8.82 ± 3.55 vs 27.92 ± 5.36 percent; P < 0.05). However, the immobilized + clenbuterol group showed an increase in weight (15.9 percent; 81.3 ± 4.6 vs 94.2 ± 4.3 mg; P < 0.05), glycogen content (92.3 percent, 0.26 ± 0.05 vs 0.50 ± 0.17 mg/100 mg; P < 0.05), and cross-sectional area (19.9 percent, 1438.1 ± 352.2 vs 1724.8 ± 365.5 µm²; P < 0.05) and a reduction in connective tissue (52.2 percent, 27.92 ± 5.36 vs 13.34 ± 6.86 percent; P < 0.05). Statistical analysis was performed using Kolmogorov-Smirnov and homoscedasticity tests. For the muscle weight and muscle glycogen content, two-way ANOVA and the Tukey test were used. For the cross-sectional area and connective tissue content, Kruskal-Wallis and Tukey tests were used. This study emphasizes the importance of anabolic pharmacological...


Subject(s)
Animals , Male , Rats , Adrenergic beta-Agonists/pharmacology , Clenbuterol/pharmacology , Connective Tissue/drug effects , Glycogen/analysis , Immobilization , Muscle, Skeletal/drug effects , Adrenergic beta-Agonists/administration & dosage , Clenbuterol/administration & dosage , Muscle Fibers, Skeletal/drug effects , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Muscular Atrophy/prevention & control , Organ Size/drug effects , Rats, Wistar , Time Factors
11.
Indian J Physiol Pharmacol ; 2008 Apr-Jun; 52(2): 141-8
Article in English | IMSEAR | ID: sea-108676

ABSTRACT

Nigella sativa (N. sativa) has a long history of use in folk medicine. In a current study performed in this laboratory, two-month dietary supplementation with N. sativa extract to normal rats has shown a homogenous cardiac hypertrophy and enhanced cardiac contractility at baseline conditions. In the present study, shorter (one-month) duration of oral N. sativa administration was adopted to detect possible earlier cardiac responses. In addition, in vitro cardiac stress by the beta adrenoceptor agonist isoproterenol was used to assess the intrinsic cardiac reserve mechanisms. The hearts of Nigella-treated rats developed a moderate but significant hypertrophy that was evident by an increase in the heart weight to body weight ratio. The observed Nigella-induced cardiac hypertrophy was associated with an increase in the baseline cardiac inotropic properties as well as the maximal peak tension generation upon progressive cardiac stress by isoproterenol infusion. The demonstrated selective enhancement of the inotropic reserve favours the physiological nature of Nigella-induced cardiac hypertrophy, similar to that provoked by exercise training.


Subject(s)
Adaptation, Physiological , Administration, Oral , Adrenergic beta-Agonists/pharmacology , Animals , Cardiomegaly/chemically induced , Cardiotonic Agents/pharmacology , Dietary Supplements , Dose-Response Relationship, Drug , Heart Rate/drug effects , Isoproterenol/pharmacology , Male , Myocardial Contraction/drug effects , Nigella sativa , Perfusion , Plant Extracts/administration & dosage , Rats , Rats, Wistar , Time Factors , Ventricular Pressure/drug effects
13.
Indian J Physiol Pharmacol ; 2007 Jan-Mar; 51(1): 49-54
Article in English | IMSEAR | ID: sea-106558

ABSTRACT

Airways are the primary target of lead exposure from atmospheric pollution, its effect on airway smooth muscle and their responsiveness to bronchoactive agents is not clearly understood. In the present investigation the effect of lead on the isolated airway smooth muscle activity was studied in organ bath set-up. Further the involvement of airway epithelium was examined and the responsiveness of airway smooth muscle to adenosine, acetylcholine (bronchoconstrictors) and isoproterenol (bronchodilator) was also investigated. Lead in concentration of 10(-12) M to 10(-4) M produced concentration-dependant contractile response in rat tracheal rings. Acetylcholine and adenosine induced concentration-dependent contractile response was slightly inhibited after lead exposure. The relaxant response to isoproterenol was also inhibited in lead exposed tissues. Epithelium removal did not significantly change the contractile response to lead suggesting that the lead induced contraction of airway smooth muscle is epithelium independent.


Subject(s)
Acetylcholine/pharmacology , Adenosine/pharmacology , Adrenergic beta-Agonists/pharmacology , Animals , Bronchodilator Agents/pharmacology , Cholinergic Agents/pharmacology , Dose-Response Relationship, Drug , Epithelium/drug effects , Isoproterenol/pharmacology , Male , Muscle Contraction/drug effects , Muscle Relaxation/drug effects , Muscle, Smooth/drug effects , Organometallic Compounds/pharmacology , Rats , Rats, Wistar , Sympathomimetics/pharmacology , Trachea/drug effects , Vasodilator Agents/pharmacology
14.
J. pediatr. (Rio J.) ; 82(5,supl): S213-S221, Nov. 2006. tab, graf
Article in English | LILACS | ID: lil-441741

ABSTRACT

OBJETIVO: Comparar os antagonistas de leucotrienos (ARLT) aos outros grupos de medicamentos utilizados para tratar a asma e a rinite alérgica. FONTES DOS DADOS: MEDLINE, LILACS e Biblioteca Cochrane. Palavras chaves: leucotrienos, antileucotrienos, tratamento da asma, tratamento da rinite alérgica, asma e rinite alérgica. Procurou-se agrupar os principais trabalhos e revisões sobre o assunto. SíNTESE DOS DADOS: Os ARLT são mais eficazes do que placebo e potencializam os efeitos dos corticosteróides inalados. A associação de corticosteróides inalados com agentes beta2 agonistas de longa duração (LABA) é mais eficaz do que a associação de cortiscoteróides inalados + ARLT. Embora pareça racional o uso de ARLT na crise aguda de asma e rinite alérgica, mais estudos são necessários para comprovar esse benefício. Os ARLT promovem redução no tempo de hospitalização e no número de crises de sibilância em lactentes com bronquiolite viral aguda pelo vírus respiratório sincicial e na sibilância recorrente após bronquiolite viral aguda. Os ARLT são menos eficazes que os corticosteróides intranasais no manejo da rinite alérgica. Os ARLT são eficazes na asma induzida por exercício (AIE), embora não constituam a primeira linha de tratamento. CONCLUSÃO: Estudos controlados e randomizados mostram que os corticosteróides inalados são as drogas de escolha para o tratamento da asma persistente e rinite alérgica. :Não existem evidências suficientes para recomendar o uso de ARLT como medicamento de primeira linha (monoterapia) em crianças com asma (nível I). Nas crianças que não podem usar corticosteróides inalados, os ARLT podem ser uma alternativa (nível II).


OBJECTIVE: To compare leukotriene antagonists (LTA) to other groups of drugs used in asthma and allergic rhinitis treatment. SOURCES: MEDLINE, LILACS and Cochrane Library. Keywords: leukotrienes, antileukotrienes, asthma treatment, allergic rhinitis treatment, asthma and allergic rhinitis. An attempt was made to group the main studies and reviews about this topic. SUMMARY OF THE FINDINGS: LTA are more efficient than placebo and enhance the effects of inhaled corticosteroids. The association of inhaled corticosteroids with long-acting beta2-agonists is more efficient than the association of inhaled corticosteroids + LTA. Although use of LTA in acute asthma attacks and allergic rhinitis seems reasonable, more studies are needed to confirm this benefit. LTA reduce hospitalization time and the number of wheezing attacks in infants with acute viral bronchiolitis caused by respiratory syncytial virus, as well as recurrent wheezing after acute viral bronchiolitis. LTA are less efficient than intranasal corticosteroids for allergic rhinitis management. LTA are efficient in exercise-induced asthma, although they are not the first-line treatment. CONCLUSIONS: Controlled and randomized studies show that inhaled corticosteroids are the drugs of choice to treat persistent asthma and allergic rhinitis. There is not enough evidence to recommend the use of LTA as first-line drug (monotherapy) in children with asthma (level I). For children who cannot use inhaled corticosteroids, LTA may be a good alternative (level II).


Subject(s)
Humans , Infant , Child , Adrenal Cortex Hormones/therapeutic use , Adrenergic beta-Agonists/therapeutic use , Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Leukotriene Antagonists/therapeutic use , Rhinitis/drug therapy , Acute Disease , Administration, Inhalation , Adrenal Cortex Hormones/pharmacology , Adrenergic beta-Agonists/pharmacology , Anti-Asthmatic Agents/pharmacology , Asthma, Exercise-Induced/drug therapy , Drug Combinations , Leukotriene Antagonists/pharmacology , Leukotrienes/classification , Leukotrienes/metabolism , Leukotrienes/pharmacology , Membrane Proteins/metabolism , Membrane Proteins/physiology , Practice Guidelines as Topic , Receptors, Leukotriene/metabolism , Receptors, Leukotriene/physiology , Respiratory System/drug effects , Treatment Outcome
15.
Indian J Exp Biol ; 2006 Jun; 44(6): 448-58
Article in English | IMSEAR | ID: sea-57108

ABSTRACT

The aim of this study was to determine the contribution of beta-adrenoceptor activation in the reconstruction of the structural and functional organization of denervated skeletal muscle. beta-agonists, clenbuterol (1.2 mg/kg body weight) and isoproterenol (2 mg/kg body weight), administration (daily oral administration; maximum 7 days) to normal innervated rats as well as denervated animals caused muscle hypertrophy. An increase in mean fiber diameter confirmed this stimulated growth both in normal innervated and denervated rat gastrocnemius muscle. Examination of muscle nuclei from treated but normal innervated rat gastrocnemius exhibited features like large size, active nucleoplasm and an increase in their number per fiber cross section and per mm mean fiber length indicating towards an elevated biosynthetic activity in tissue in the presence of beta adrenoceptor agonists. Administration of drugs to normal innervated animals resulted in an emergence of central muscle nuclei. The hyperactive and enlarged muscle nuclei ultimately organized themselves into unusually elongated nuclear streaks. beta agonist treatment to denervated rats resulted in amelioration of atrophic state of tissue characterized by hypertrophy of muscle fibers thus lending to a restoration of structural organization of tissue. Bizarre shapes of nuclei in denervated muscle tend to recover to that characteristic to normal innervated muscle in presence of clenbuterol and isoproterenol hydrochloride. All observations were confirmed by administering butoxamine, a beta-adrenoceptor antagonist along with beta-agonists. The results suggests that both clenbuterol and isoproterenol hydrochloride are capable of mimicking normal innervation functions in skeletal muscle and thus play important role in the structural and functional reorganization of tissue. Amelioration of denervation atrophy in rat gastrocnemius in the presence of beta-agonists supports this.


Subject(s)
Adrenergic beta-Agonists/pharmacology , Animals , Clenbuterol/pharmacology , Isoproterenol/pharmacology , Male , Muscle Denervation , Muscle, Skeletal/drug effects , Rats , Receptors, Adrenergic, beta/metabolism
16.
Indian J Biochem Biophys ; 2006 Jun; 43(3): 160-6
Article in English | IMSEAR | ID: sea-29112

ABSTRACT

beta-Adrenoceptor agonists are reported to induce skeletal muscle hypertrophy and hence serve as valuable adjunct to the treatment of wasting disorders. In the present study, we attempted to find out whether metabolic and physiologic characteristics of fibres are important in determining skeletal muscle response to clenbuterol (an adrenergic receptor agonist) therapy, as proposed in the treatment of wasting disorders. The treatment of mice with clenbuterol (2 mg/kg body wt for 30 days) resulted in skeletal muscle hypertrophy, more common amongst fast-twitch glycolytic fibres/muscle, with increase in body mass and a parallel rise in muscle mass to body mass ratio. Measurement of fibre diameters in soleus (rich in slow-twitch oxidative fibres), ALD or anterior latissimus dorsi (with a predominance of fast-twitch glycolytic fibres) and gastrocnemius (a mixed-type of muscle) from clenbuterol-treated mice for 30 days revealed noticeable increase in the per cent population of narrow slow-twitch fibre and a corresponding decline in white-type or fast-twitch glycolytic fibres in gastrocnemius and ALD. As revealed by counting of muscle cells in soleus, narrow red fibres declined with corresponding increase in white-type glycolytic fibres population. A significant decline in the succinic dehydrogenase activity was observed, thereby suggesting abnormality in oxidative activity of skeletal muscles in response to clenbuterol therapy.


Subject(s)
Adrenergic beta-Agonists/pharmacology , Animals , Clenbuterol/pharmacology , Hypertrophy , Male , Mice , Muscle Fibers, Fast-Twitch/drug effects , Muscle Fibers, Slow-Twitch/drug effects , Muscle, Skeletal/drug effects , Succinate Dehydrogenase/metabolism , Wasting Syndrome/drug therapy
17.
Indian J Exp Biol ; 2006 May; 44(5): 371-6
Article in English | IMSEAR | ID: sea-60609

ABSTRACT

Daily oral administration of isoproterenol hydrochloride (60 mg/kg body weight; for 30 days) a beta-receptor agonist to normal innervated and denervated adult male Swiss albino mice confirmed its ability to induce skeletal muscle hypertrophy and reverse denervation atrophy respectively. Measurement of total tissue proteins and dry muscle mass showed 15-17% increase with 6% rise of hypertrophy index in gastrocnemius muscle. Hydroxyproline assay employed to measure the total tissue collagen exhibited 45% increase in collagen in normal innervated gastrocnemius muscle in response to beta agonist treatment. beta-adrenoceptor agonist ameliorated denervation atrophy along with further increase in collagen content of denervated gastrocnemius muscle.


Subject(s)
Adrenergic beta-Agonists/pharmacology , Animals , Collagen/biosynthesis , Denervation , Male , Mice , Muscle, Skeletal/drug effects
18.
Indian J Biochem Biophys ; 2006 Apr; 43(2): 82-7
Article in English | IMSEAR | ID: sea-28935

ABSTRACT

Beta-Agonists though have been widely studied for their protein anabolic effects in skeletal muscles, but the lipid status under work stress and agonist treatment have not been understood well in the skeletal muscles and heart of rat. In the present study, adult male Wistar rats were subjected to work overload stress and beta agonist isoproterenol treatment (2 mg kg(-1) day(-1) intraperitoneally) to examine, whether it attenuates work stress-induced changes or not. Simultaneously, beta2 antagonist butoxamine (2 mg kg(-1) day(-1) intraperitoneally) was administered to another isoproterenol-treated group. Work stress led to myofibrillar degeneration as well as rapid utilization of lipid to meet increased energy demands and for muscle repair, which was reflected through histochemical localization of lipids and biochemical estimation of cholesterol and triglycerides. Significantly decreased cholesterol levels in skeletal muscles and heart muscles were noticed. As expected, isoproterenol reversed the conditions by raising cholesterol and triglyceride levels significantly in the skeletal muscles and also by ameliorating the degenerative changes in muscle fibres as induced by work overload. However, severe accumulation of lipids in heart infers towards deleterious effects of isoproterenol on heart and thus remains a limiting factor for its immediate clinical application. Further research is needed to separate desirable effects of beta agonists on skeletal muscles from any undesirable effects on the heart, so as to optimize their therapeutic potential.


Subject(s)
Adrenergic beta-Agonists/pharmacology , Animals , Heart/drug effects , Isoproterenol/pharmacology , Male , Motor Activity/physiology , Muscle, Skeletal/drug effects , Muscular Atrophy/drug therapy , Rats , Rats, Wistar , Stress, Physiological/physiopathology
19.
Braz. j. med. biol. res ; 38(12): 1799-1805, Dec. 2005. ilus
Article in English | LILACS | ID: lil-417188

ABSTRACT

The objective of the present investigation was to perform a 14-day time-course study of treatment with salbutamol, a ß2 adrenoceptor agonist, on rat soleus muscle in order to assess fiber type selectivity in the hypertrophic response and fiber type composition. Male Wistar rats were divided into four groups: control (N = 10), treated with salbutamol (N = 30), denervated (N = 30), and treated with salbutamol after denervation (N = 30). Salbutamol was injected intraperitoneally in the rats of the 2nd and 4th groups at a concentration of 0.3 mg/kg twice a day for 2 weeks. The muscles were denervated using the crush method with pean. The animals were sacrificed 3, 6, 9, 12, and 14 days after treatment. Frozen cross-sections of soleus muscle were stained for myosin ATPase, pH 9.4. Cross-sectional area and percent of muscle fibers were analyzed morphometrically by computerized image analysis. Treatment with salbutamol induced hypertrophy of all fiber types and a higher percentage of type II fibers (21 percent) in the healthy rat soleus muscle. Denervation caused marked atrophy of all fibers and conversion from type I to type II muscle fibers. Denervated muscles treated with salbutamol showed a significantly larger cross-sectional area of type I muscle fibers, 28.2 percent compared to the denervated untreated muscle. Moreover, the number of type I fibers was increased. These results indicate that administration of salbutamol is able to induce changes in cross-sectional area and fiber type distribution in the early phase of treatment. Since denervation-induced atrophy and conversion from type I to type II fibers were improved by salbutamol treatment we propose that salbutamol, like other ß2 adrenoceptor agonists, may have a therapeutic potential in improving the condition of skeletal muscle after denervation.


Subject(s)
Animals , Male , Rats , Albuterol/pharmacology , Muscle Denervation , Muscle Fibers, Skeletal , Muscle, Skeletal/drug effects , Adrenergic beta-Agonists/pharmacology , Muscular Atrophy , Muscle, Skeletal/innervation , Rats, Wistar
20.
Indian J Exp Biol ; 2004 Sep; 42(9): 913-8
Article in English | IMSEAR | ID: sea-57259

ABSTRACT

Present study was conducted on prostaglandin F2alpha (PGF2alpha), oxytocin, (OT), potassium chloride (KCI) and barium chloride (BaCl2) pre-contracted perimetrial uterine strips of dioestrus and pregnant buffaloes to evaluate the tocolytic efficacy of selective beta2 adrenoceptor agonists-albuterol (salbutamol) and terbutaline. Cumulative concentration-response curves of both the beta2 adrenoceptor agonists were constructed and the mean effective concentration (EC50) values determined and compared statistically. Based on the comparative EC50 values in relaxing the pre-contracted uterine strips with different spasmogens, the rank order potency of albuterol was found to be--PGF2alpha > BaCl2 > OT > KCl on uterine strips from dioestrus animals, while OT> BaCl2> PGF2alpha >KCl on the uterine strips of pregnant buffaloes. The rank order potency of terbutaline on uterine strips from dioestrus stage animals was- BaCl2 > OT > KCl > PGF2alpha, while BaCl2 > PGF2alpha > KCl > OT on uterine tissues of pregnant animals. Thus, irrespective of the state of uterus, whether gravid or non-gravid, KCl-depolarized uterine tissues required comparatively higher concentrations of albuterol or terbutaline to produce tocolytic effect. High concentrations of K+ in biophase may have interfered with the beta2 adrenoceptor agonists-induced outward K+ current and hyperpolarization. From the results of present study, it was evident that selective beta2 adrenergic agonists had good tocolytic efficacy on the uterus of buffaloes. Further, indirectly the possibility of existence and activation of K(Ca) channels by selective beta2 adrenoceptor agonists in mediating tocolysis of buffalo myometrium can not be ruled out, however, detailed studies using specific K(Ca) channel blockers are required for characterizing the nature of such channels in buffalo uterus.


Subject(s)
Abortifacient Agents, Nonsteroidal/pharmacology , Adrenergic beta-Agonists/pharmacology , Albuterol/pharmacology , Animals , Barium Compounds/pharmacology , Buffaloes , Chlorides/pharmacology , Dinoprost/pharmacology , Female , Oxytocin/pharmacology , Potassium Chloride/pharmacology , Pregnancy , Receptors, Adrenergic, beta-2/antagonists & inhibitors , Terbutaline/pharmacology , Tocolytic Agents/pharmacology , Uterine Contraction/drug effects , Uterus/drug effects
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