The beta 1-adrenoceptor as antigen: functional aspects.
The sera of patients with myocarditis and idiopathic dilated cardiomyopathy contain agonistic autoantibodies that bind to the beta 1-adrenoceptor. These antibodies recognize epitopes on either the first or second extracellular loop of this receptor and exert in cultured neonatal rat heart myocytes a positive chronotropic effect. This effect is eliminated by beta 1-adrenoceptor blockade as well as by peptides corresponding to the first or second extracellular loop of the human beta 1-adrenoceptor. The antibodies realize their effects mainly via the beta-adrenoceptor-adenylate cyclase-protein kinase A cascade.
Wallukat
G
G
Max-Delbrück-Centrum für Molekulare Medizin, Berlin, Germany.
Kayser
A
A
Wollenberger
A
A
D000262:Adenylyl Cyclases / Q000502:physiology; D000595:Amino Acid Sequence; D000818:Animals; D000831:Animals, Newborn; D001323:Autoantibodies / Q000097:blood*; D002311:Cardiomyopathy, Dilated / Q000276:immunology*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000502:physiology; D000939:Epitopes / Q000276:immunology*; D006339:Heart Rate / Q000276:immunology; D006801:Humans; D009200:Myocardial Contraction / Q000276:immunology; D009205:Myocarditis / Q000276:immunology*; D051381:Rats; D017208:Rats, Wistar; D018340:Receptors, Adrenergic, alpha-1 / Q000276:immunology*
D001323:Autoantibodies; D000939:Epitopes; D018340:Receptors, Adrenergic, alpha-1; D017868:Cyclic AMP-Dependent Protein Kinases; D000262:Adenylyl Cyclases