Normal responsiveness of serum parathyroid hormone to beta-adrenergic blockade in patients with secondary hyperparathyroidism

Infusion of calcium gluconate (15 mg Ca++/kg body weight in 4 h) to 6 patients with secondary hyperparathyroidism (due to mild renal insufficiency) decreased serum parathyroid hormone (PTH) levels to the same degree (on a percent basis) as in normal subjects. Serum PTH values at 4 h were 60 +/- 4.5 (SEM)% of baseline in the patients and 59 +/- 2.9% of baseline in the normal subjects. Infusion of propranolol (1 mg i.v. bolus followed by an infusion of 60 micrograms/min for 2 h) to 7 additional patients with secondary hyperparathyroidism also decreased serum PTH to the same degree as in normal subjects. Serum PTH values at 2 h were 68 +/- 10.4% of baseline in the patients and 68 +/- 3.3% of baseline in the normal subjects. The studies indicate normal responsiveness of serum PTH to calcium or beta-adrenergic blockade in secondary hyperparathyroidism due to mild renal insufficiency.