Early Effects of Parathormone and Calcitonin on the Number of Osteoclasts and on Serum-Calcium in Rats

Abstract

Using succinic dehydrogenase staining of osteoclasts, the authors have studied the early effects on these cells of parathormone and calcitonin in rats. Thirty minutes after injection of the hormones the number of osteoclasts had increased (parathormone) or decreased (calcitonin), associated with inverse changes in total serum-calcium. The results confirm earlier studies showing the remarkably rapid changes in the number of osteoclasts after substances acting on serum calcium.

Key Words:

• calcitonin
• osteoclasts
• parathyroid hormone
• serum calcium