Abstract
Changes of serum bone Gla protein (BGP) were followed along with serum calcium and parathyroid hormone (PTH) on administration of salmon calcitonin (SCT) in patients with primary hyperparathyroidism (PHP). Intramuscular administration of 80 units of SCT in 12 patients with PHP resulted in a significant fall of serum Ca from 30 minutes after the injection, reaching the lowest value 3-12 hours later, and returned to the pre-administration level 24 hours later. Serum PTH showed a tendency of rise after CT administration reaching a significantly higher level 12 hours later. Serum BGP showed a significant decrease 3-12 hours, returning the previous level 24 hours later. After SCT administration, a significant positive correlation was noted between the maximum fall of serum BGP and preadministration serum BGP values. On intramuscular injection of 40 units SCT morning and evening on 7 consecutive days in 4 patients with PHP, both serum Ca and BGP tended to decrease during the initial period of administration, but the effect fell of within a few days.
Thus, SCT directly inhibits the enhanced bone resorption in patients with PHP. Also, a possibility exists that SCT may exert a direct or indirect inhibitory action on enhanced bone formation.
