Regulation of β₂-adrenergic receptors on mononuclear leukocytes in patients with acute ischemic heart disease

Objective: To investigate relationships between acute adrenergic stress, plasma catecholamine concentrations, and β₂-adrenergic receptors. Design: Prospective, descriptive study. Setting: Emergency medical service at a university hospital. Patients: Twenty-seven patients with out-of-hospital cardiac arrest (n = 11), myocardial infarction (n = 6), and angina pectoris (n= 10), and 12 control subjects. Interventions: None. Measurements and Main Results: Mononuclear leukocyte β₂-adrenergic receptor density and affinity were measured in patients 15 mins after successful cardiopulmonary resuscitation and after the diagnosis of myocardial infarction or angina pectoris, respectively, and were measured as well in control subjects. Plasma concentrations of catecholamines, glucose, and lactate were simultaneously measured with heart rate and blood pressure. After cardiac arrest, the density of β₂-adrenergic receptors (1858 ± 188 sites/cell [p < .01]), plasma epinephrine concentration (31,990 14,526 pg/mL [174.6 ± 79.3 nmol/L] [p < .01]), heart rate (100 ± 6 beats/min [p < .01]), glucose concentration (14.9 ± 0.8 mmol/L [p < .01]), and lactate concentration (10.9 ± 0.6 mmol/L [p < .01]) were increased in patients compared with those values in healthy controls. Conclusion: Acute maximal stress, such as after cardiac arrest, is associated with an increase in the density of β₂-adrenergic receptors on mononuclear leukocytes derived from patients after successful cardiopulmonary resuscitation.