Autoantibodies against the -adrenergic receptor in human myocarditis and dilated cardiomyopathy: -adrenergic agonism without desensitization

Abstract

The serum of patients with myocarditis and dilated cardiomyopathy contains immunoglobulins capable of causing in vitro acceleration of beating of neonatal rat heart myocytes. This effect is stereoselectively inhibited by (-)-propranolol and is inhibited also by the beta 1-selective adrenergic antagonists, bisoprolol and metoprolol. This effect is not reversed by washing and continues unabated for at least 24 h.