Characterization of lymphocyte beta-adrenergic receptors at rest and during exercise in ambulatory patients with chronic congestive heart failure.

To investigate beta-adrenergic receptor dysfunction in congestive heart failure (CHF), the density of lymphocyte beta receptors and adenylate cyclase activity was measured at rest and at peak exercise in 30 patients with CHF and 7 age-matched control subjects. At rest, patients with CHF had reduced beta-receptor density (normals 33 +/- 2; CHF 21 +/- 2 fmol/mg protein; p less than 0.01) and isoproterenol-stimulated adenylate cyclase activity (normals 50 +/- 9; CHF 28 +/- 4 pmol/mg protein/min; p less than 0.05). Sodium fluoride-stimulated adenylate cyclase activity was also reduced (normals 98 +/- 17; CHF 48 +/- 12 pmol/mg protein/min; p less than 0.01). In the patients with CHF, there was no significant correlation between receptor density and peak exercise VO2, ejection fraction or resting plasma catecholamines. In the normal subjects, maximal exercise increased beta-receptor density by 100% (rest 33 +/- 2; exercise 67 +/- 7 fmol/mg protein) and isoproterenol-stimulated adenylate cyclase activity by 66% (rest 50 +/- 9; exercise 83 +/- 18 pmol/mg protein/min (both p less than 0.01]. In contrast, patients with CHF exhibited only a 58% increase in beta-receptor density (rest 20 +/- 3; exercise 32 +/- 6 fmol/mg protein; p less than 0.01) and no significant change in isoproterenol-stimulated adenylate cyclase activity (rest 27 +/- 5; exercise 24 +/- 5 pmol/mg protein/min).(ABSTRACT TRUNCATED AT 250 WORDS)