Nuclear fuel cycle. The nuclear fuel cycle, also called nuclear fuel chain, is the progression of nuclear fuel through a series of differing stages.
Hormone responsiveness does appear if the osteoclasts are cultured in conditioned medium from osteoblasts that first have been exposed to PTH, suggesting an important role for osteoblasts in PTH-dependent bone resorption [citing references as early as 1986].
The parathyroid glands, located on the dorsal aspect of the thyroid gland, secrete parathyroid hormone (PTH), which causes an increase in blood calcium levels by targeting bone, the intestine, and the kidneys. PTH is the antagonist of calcitonin.