{"title":"Differential relevance of beta-adrenoceptor subtypes in modulating the rat brown adipocytes function.","authors":"E Nisoli, C Tonello, M O Carruba","doi":"","DOIUrl":null,"url":null,"abstract":"<p><p>The potencies and intrinsic activities on cyclic AMP accumulation and lipolysis of various selective beta 3-adrenoceptor agonists were studied in brown adipocytes and compared to those of the nonselective, (-)-isoprenaline, and conventional beta 1- (dobutamine) and beta 2-adrenoceptor (salbutamol) agonists. (-)-Isoprenaline, dobutamine and salbutamol were more potent stimulants of lipolysis than of cyclic AMP accumulation, while the selective beta 3-adrenoceptor agonists had similar potencies for these two functions. Apparent pA2 values of the selective beta 1-(CGP20712A) and beta 2-adrenoceptor (ICI118551) antagonist for inhibition of adenylyl cyclase stimulation by (-)-isoprenaline and the beta 3-adrenoceptor agonists, BRL37344, SR58611A, and ICI215001, indicated that (-)-isoprenaline can stimulate the enzyme through a relevant beta 1-adrenergic component, while the other drugs activate the enzyme mainly by acting on the beta 3-adrenoceptors. On the contrary, antagonism of the lipolysis yielded apparent pA2 values for CGP20712A and ICI118551, suggesting that (-)-isoprenaline, like all the beta 3-adrenoceptor agonists, stimulated the brown adipose tissue lipid metabolism mainly through an action on beta 3-adrenoceptors.</p>","PeriodicalId":8166,"journal":{"name":"Archives internationales de pharmacodynamie et de therapie","volume":"329 3","pages":"436-53"},"PeriodicalIF":0.0000,"publicationDate":"1995-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Archives internationales de pharmacodynamie et de therapie","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
The potencies and intrinsic activities on cyclic AMP accumulation and lipolysis of various selective beta 3-adrenoceptor agonists were studied in brown adipocytes and compared to those of the nonselective, (-)-isoprenaline, and conventional beta 1- (dobutamine) and beta 2-adrenoceptor (salbutamol) agonists. (-)-Isoprenaline, dobutamine and salbutamol were more potent stimulants of lipolysis than of cyclic AMP accumulation, while the selective beta 3-adrenoceptor agonists had similar potencies for these two functions. Apparent pA2 values of the selective beta 1-(CGP20712A) and beta 2-adrenoceptor (ICI118551) antagonist for inhibition of adenylyl cyclase stimulation by (-)-isoprenaline and the beta 3-adrenoceptor agonists, BRL37344, SR58611A, and ICI215001, indicated that (-)-isoprenaline can stimulate the enzyme through a relevant beta 1-adrenergic component, while the other drugs activate the enzyme mainly by acting on the beta 3-adrenoceptors. On the contrary, antagonism of the lipolysis yielded apparent pA2 values for CGP20712A and ICI118551, suggesting that (-)-isoprenaline, like all the beta 3-adrenoceptor agonists, stimulated the brown adipose tissue lipid metabolism mainly through an action on beta 3-adrenoceptors.