title: In vivo isoproterenol treatment leads to downregulation of the mRNA encoding the cAMP response element binding protein in the rat heart.
abstract: The expression of different myocardial regulatory proteins is altered in human heart failure, e.g., beta 1-adrenoceptors, G-proteins and others. Similar changes in rats after 4 days treatment with isoproterenol led to the hypothesis of the cAMP pathway involved in these changes. In different cell types cAMP-dependent transcriptional activation is mediated by the cAMP-response element binding protein (CREB) which was recently shown to be expressed and phosphorylated in the human heart. Here, by the reverse transcriptase-polymerase chain reaction two alternatively spliced isoforms of CREB mRNA were found to be expressed in rat ventricles. Both isoforms were down-regulated in the ventricles of rats treated in vivo with isoproterenol (2.4 mg/kg per day) for 4 days proposing a possible mechanism involved in expressional changes mentioned above.
mesh_terms: D000318:Adrenergic beta-Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D001835:Body Weight / Q000187:drug effects; D017362:Cyclic AMP Response Element-Binding Protein / Q000096:biosynthesis*; D017931:DNA Primers; D005786:Gene Expression Regulation / Q000187:drug effects*; D006321:Heart / Q000187:drug effects*; D006352:Heart Ventricles; D006801:Humans; D007263:Infusions, Parenteral; D007545:Isoproterenol / Q000008:administration & dosage / Q000494:pharmacology*; D007700:Kinetics; D008297:Male; D008969:Molecular Sequence Data; D009206:Myocardium / Q000378:metabolism*; D009929:Organ Size / Q000187:drug effects; D010766:Phosphorylation; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D013997:Time Factors
chemical_list: D000318:Adrenergic beta-Agonists; D017362:Cyclic AMP Response Element-Binding Protein; D017931:DNA Primers; D012333:RNA, Messenger; D007545:Isoproterenol