Objective: To analyze the association between β2-adrenergic receptor (β2-AR)genetic polymorphisms and nocturnal asthmatic patients of Chinese Han nationality. Methods: Polymerase chain reaction-allele specific oligo...Objective: To analyze the association between β2-adrenergic receptor (β2-AR)genetic polymorphisms and nocturnal asthmatic patients of Chinese Han nationality. Methods: Polymerase chain reaction-allele specific oligonucleotide hybridization assay was used to determine 16 and 27 locus alleles of β2-AR genetic polymorphisms in 25 nocturnal asthmatic patients( NA group). 22 nonnocturnal asthmatic patients (NNA group) and 72 healthy people ( control group). All subjects were from Chinese Han nationality. Results. The distribution frequency of genotype Arg/Arg, Arg/Gly, and Gly/Gly at β2-AR 16 loci was 12%, 16% and 72% in NA group; and was 27%, 41% and 32% in NNA group. There was significant increase in the frequency of genotype Gly/Gly and allele Gly in NA group, compared with NNA group(P<0.01). However, there was no significant difference in the frequency of genotype Gly/Gly and allele Gly in NNA group, compared with control group. No significance in the frequency of the genotypes and alleles of β2-AR27 loci among the three groups(P>0.05). Conclusion: The Gly16 polymorphism of β2-AR is overrepresented in nocturnal asthmatic patients, correlated with nocturnal asthma and therefore appears to be an important genetic factor in the expression of this asthmatic phenotype.展开更多
We studied the activation of β2-adrenergic receptor（β2AR） by norepinephrine, epinephrine and isoprote- renol using docking and molecular dynamics（MD） simulation. The simulation was done on the assumption that β...We studied the activation of β2-adrenergic receptor（β2AR） by norepinephrine, epinephrine and isoprote- renol using docking and molecular dynamics（MD） simulation. The simulation was done on the assumption that β2AR was surrounded with explicit water and infinite lipid bilayer membrane at body temperature. So the result should be close to that under the physiological conditions. We calculated the structure of binding sites in β2AR for the three ac- tivators. We also simulated the change of the conformation ofβ2AR in the transmembrane regions（TMs）, in the mo- lecular switches, and in the conserved DRY（Aspartic acid, Arginine and Tyrosine） motif. This study provides detailed information concerning the structure ofβ2AR during activation process.展开更多
Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride.Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor corte...Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride.Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor cortex injury.The aim of this study was to analyze the role ofα-adrenergic receptors in the restoration of motor deficits in recovering rats after brain damage.The rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours,3 days,and 20 days after ferrous chloride-induced cortical injury:saline,clonidine,efaroxan(a selective antagonist ofα-adrenergic receptors)and clonidine+efaroxan.The sensorimotor score,the immunohistochemical staining forα-adrenergic receptors,and norepinephrine levels were evaluated.Eight hours post-injury,the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased,and these effects were maintained 3 days post-injury.However,20 days later,clonidine administration diminished norepinephrine levels in the pons compared with the sham group.This effect was accompanied by sensorimotor deficits.These effects were blocked by efaroxan.In conclusion,an increase inα-adrenergic receptor levels was observed after injury.Clonidine restores motor deficits in rats recovering from cortical injury,an effect that was prevented by efaroxan.The underlying mechanisms involve the stimulation of hypersensitiveα-adrenergic receptors and inhibition of norepinephrine activity in the locus coeruleus.The results of this study suggest thatαreceptor agonists might restore deficits or impede rehabilitation in patients with brain injury,and therefore pharmacological therapies need to be prescribed cautiously to these patients.展开更多
Objectives To investigate the effects of β2-adrenergic antagonist on cytosolic Ca^2 ＋ （[Ca^2＋ ]i） in ventricular myocytes from infarcted rat heart. Methods A ligature was placed around left anterior descending co...Objectives To investigate the effects of β2-adrenergic antagonist on cytosolic Ca^2 ＋ （[Ca^2＋ ]i） in ventricular myocytes from infarcted rat heart. Methods A ligature was placed around left anterior descending coronary artery of rat hearts. Rats in the control group were sham-operated. Cardiomyocytes were dissociated at two, four, eight weeks after myocardial infarction （MI） and [Ca^2＋]i was measured via fura-2 fluorescence. The response of cardiomyocytes to isoproterenol in presence or absence of betal-adrenergic antagonist atenolol, beta2-adrenergic antagonist ICI118, 551 or non-selective β1, 2- adrenergic antagonists propranolol was examined. Results The followings were found that ICI 118, 551 had no significant effects on the rise of [Ca^2＋]i induced by isoproterenol in normal ventricular myocytes （P 〉 0.05）, ICI118, 551 only significantly attenuated the rise of [Ca^2＋]i induced by isoproterenol at four weeks and eight weeks after MI （24.5%±5.7% vs 57.8% ± 13.2%, P〈 0.01; 12.2%±7.9% vs 44.6%±11.3%, P〈 0.01）. Atenolol had suppressive effects only in the control group and the post-MI group of two weeks （P 〈 0.05）, and propranolol had suppressive effects in the control and all the three post-MI groups （P 〈 0.01）. Conclusions Beta2-adrenergic antagonist ICI118, 551 may exert negative effects on Ca^2＋ overload initiated by sympathetic stimulation after MI.展开更多
Objective： To investigate the effects of gene transfer of a β-adrenergic receptor（β-AR） kinase inhibitor（β ARIct） on pulmonary β2-adrenergic receptor and cAMP following β2-AR agonist treatment in asthmatic m...Objective： To investigate the effects of gene transfer of a β-adrenergic receptor（β-AR） kinase inhibitor（β ARIct） on pulmonary β2-adrenergic receptor and cAMP following β2-AR agonist treatment in asthmatic mice, and to analyze the relationship between the routes of gene delivery and the changes of β2AR and cAMP. Methods： BALB/c mice were sensitized and challenged by ovalbumin to establish the asthmatic model treated with βAR agonist （salbutamol injected intramuscularly）. The plasmid with the expression of βARKct was constructed and βARKct gene transfer was performed through intravenous injection or intratracheal instillation in asthmatic mice. The gene expression was measured with Western blot analysis, and the changes of pulmonary β-AR and cAMP evaluated by Radioimmunoassay. Results： The expression of tranfered βARKct gene was detectable in lungs and it was expressed more in the lungs of the mice receiving intratracheally plasmid than those receiving intravenously. The levels of βAR and cAMP were upregulated after using plasmid-βARKct to the asthmatic mice treated with βAR agonist. Conclusion： Our results indicated that there were down-regulation of βAR and cAMP in asthmatic mice treated with βAR agonist. Gene transfer of βARKct could inhibit the extent of the down-regulation of βAR and cAMP. The route of gene delivery could also affect the degree of up-regulation of βAR and cAMP. Gene transfer βARKct may provide a novel approach to the therapeutic strategy for asthma.展开更多
To investigate the roles of autoantibodies to β 2 adrenergic receptors in the pathogenesis of asthma, the positive chronotropic action of the β 2selective adrenergic agonist, clenbuterol, was investigated on culture...To investigate the roles of autoantibodies to β 2 adrenergic receptors in the pathogenesis of asthma, the positive chronotropic action of the β 2selective adrenergic agonist, clenbuterol, was investigated on cultured neonatal rat cardiomyocytes, firstly. Then we detected the autoantibodies to β 2adrenergic receptors through the sera of patients with asthma could inhibit the positive chronotropic action of clenbuterol. The results showed that all the sera of the patients with asthma (16 cases) had the autoantibodies to β 2 adrenergic receptors; in contrast, none of the control subjects (20 cases) had the autoantibodies to β 2 adrenergic receptors, and that the inhibitory autoantibodies were IgG type. This study suggests that the autoantibodies to β 2 adrenergic receptors may play an important role in the pathogenesis of asthma.展开更多
文摘Objective: To analyze the association between β2-adrenergic receptor (β2-AR)genetic polymorphisms and nocturnal asthmatic patients of Chinese Han nationality. Methods: Polymerase chain reaction-allele specific oligonucleotide hybridization assay was used to determine 16 and 27 locus alleles of β2-AR genetic polymorphisms in 25 nocturnal asthmatic patients( NA group). 22 nonnocturnal asthmatic patients (NNA group) and 72 healthy people ( control group). All subjects were from Chinese Han nationality. Results. The distribution frequency of genotype Arg/Arg, Arg/Gly, and Gly/Gly at β2-AR 16 loci was 12%, 16% and 72% in NA group; and was 27%, 41% and 32% in NNA group. There was significant increase in the frequency of genotype Gly/Gly and allele Gly in NA group, compared with NNA group(P<0.01). However, there was no significant difference in the frequency of genotype Gly/Gly and allele Gly in NNA group, compared with control group. No significance in the frequency of the genotypes and alleles of β2-AR27 loci among the three groups(P>0.05). Conclusion: The Gly16 polymorphism of β2-AR is overrepresented in nocturnal asthmatic patients, correlated with nocturnal asthma and therefore appears to be an important genetic factor in the expression of this asthmatic phenotype.
基金Supported by the Young and Middle-Aged Scientists Research Awards Foundation of Shangdong Province,China(No.BS2011SW002)the Research Foundation for Advanced Talents of Ludong University,China(No.LY2011017)
文摘We studied the activation of β2-adrenergic receptor（β2AR） by norepinephrine, epinephrine and isoprote- renol using docking and molecular dynamics（MD） simulation. The simulation was done on the assumption that β2AR was surrounded with explicit water and infinite lipid bilayer membrane at body temperature. So the result should be close to that under the physiological conditions. We calculated the structure of binding sites in β2AR for the three ac- tivators. We also simulated the change of the conformation ofβ2AR in the transmembrane regions（TMs）, in the mo- lecular switches, and in the conserved DRY（Aspartic acid, Arginine and Tyrosine） motif. This study provides detailed information concerning the structure ofβ2AR during activation process.
基金supported by Consejo Nacional de Ciencia y Tecnología(CONACy T)project CB 2016-287614(to RGP and ABN)by Scholarship Programa de Apoyo a Proyectos de Investigación e Innovación Tecnológica de la Universidad Nacional Autónoma de México(PAPIIT-UNAM)IA203319 and PAPIIT-UNAM IN216221 to(LERL)。
文摘Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride.Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor cortex injury.The aim of this study was to analyze the role ofα-adrenergic receptors in the restoration of motor deficits in recovering rats after brain damage.The rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours,3 days,and 20 days after ferrous chloride-induced cortical injury:saline,clonidine,efaroxan(a selective antagonist ofα-adrenergic receptors)and clonidine+efaroxan.The sensorimotor score,the immunohistochemical staining forα-adrenergic receptors,and norepinephrine levels were evaluated.Eight hours post-injury,the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased,and these effects were maintained 3 days post-injury.However,20 days later,clonidine administration diminished norepinephrine levels in the pons compared with the sham group.This effect was accompanied by sensorimotor deficits.These effects were blocked by efaroxan.In conclusion,an increase inα-adrenergic receptor levels was observed after injury.Clonidine restores motor deficits in rats recovering from cortical injury,an effect that was prevented by efaroxan.The underlying mechanisms involve the stimulation of hypersensitiveα-adrenergic receptors and inhibition of norepinephrine activity in the locus coeruleus.The results of this study suggest thatαreceptor agonists might restore deficits or impede rehabilitation in patients with brain injury,and therefore pharmacological therapies need to be prescribed cautiously to these patients.
文摘Objectives To investigate the effects of β2-adrenergic antagonist on cytosolic Ca^2 ＋ （[Ca^2＋ ]i） in ventricular myocytes from infarcted rat heart. Methods A ligature was placed around left anterior descending coronary artery of rat hearts. Rats in the control group were sham-operated. Cardiomyocytes were dissociated at two, four, eight weeks after myocardial infarction （MI） and [Ca^2＋]i was measured via fura-2 fluorescence. The response of cardiomyocytes to isoproterenol in presence or absence of betal-adrenergic antagonist atenolol, beta2-adrenergic antagonist ICI118, 551 or non-selective β1, 2- adrenergic antagonists propranolol was examined. Results The followings were found that ICI 118, 551 had no significant effects on the rise of [Ca^2＋]i induced by isoproterenol in normal ventricular myocytes （P 〉 0.05）, ICI118, 551 only significantly attenuated the rise of [Ca^2＋]i induced by isoproterenol at four weeks and eight weeks after MI （24.5%±5.7% vs 57.8% ± 13.2%, P〈 0.01; 12.2%±7.9% vs 44.6%±11.3%, P〈 0.01）. Atenolol had suppressive effects only in the control group and the post-MI group of two weeks （P 〈 0.05）, and propranolol had suppressive effects in the control and all the three post-MI groups （P 〈 0.01）. Conclusions Beta2-adrenergic antagonist ICI118, 551 may exert negative effects on Ca^2＋ overload initiated by sympathetic stimulation after MI.
文摘Objective： To investigate the effects of gene transfer of a β-adrenergic receptor（β-AR） kinase inhibitor（β ARIct） on pulmonary β2-adrenergic receptor and cAMP following β2-AR agonist treatment in asthmatic mice, and to analyze the relationship between the routes of gene delivery and the changes of β2AR and cAMP. Methods： BALB/c mice were sensitized and challenged by ovalbumin to establish the asthmatic model treated with βAR agonist （salbutamol injected intramuscularly）. The plasmid with the expression of βARKct was constructed and βARKct gene transfer was performed through intravenous injection or intratracheal instillation in asthmatic mice. The gene expression was measured with Western blot analysis, and the changes of pulmonary β-AR and cAMP evaluated by Radioimmunoassay. Results： The expression of tranfered βARKct gene was detectable in lungs and it was expressed more in the lungs of the mice receiving intratracheally plasmid than those receiving intravenously. The levels of βAR and cAMP were upregulated after using plasmid-βARKct to the asthmatic mice treated with βAR agonist. Conclusion： Our results indicated that there were down-regulation of βAR and cAMP in asthmatic mice treated with βAR agonist. Gene transfer of βARKct could inhibit the extent of the down-regulation of βAR and cAMP. The route of gene delivery could also affect the degree of up-regulation of βAR and cAMP. Gene transfer βARKct may provide a novel approach to the therapeutic strategy for asthma.
文摘To investigate the roles of autoantibodies to β 2 adrenergic receptors in the pathogenesis of asthma, the positive chronotropic action of the β 2selective adrenergic agonist, clenbuterol, was investigated on cultured neonatal rat cardiomyocytes, firstly. Then we detected the autoantibodies to β 2adrenergic receptors through the sera of patients with asthma could inhibit the positive chronotropic action of clenbuterol. The results showed that all the sera of the patients with asthma (16 cases) had the autoantibodies to β 2 adrenergic receptors; in contrast, none of the control subjects (20 cases) had the autoantibodies to β 2 adrenergic receptors, and that the inhibitory autoantibodies were IgG type. This study suggests that the autoantibodies to β 2 adrenergic receptors may play an important role in the pathogenesis of asthma.
