Bone and Calcium

hypocalcemia

low calcium

muscle spasm/cramp, numbness, slow heartbeat, anxiety/depression

hypercalcemia

appetite, nausea/vomiting, dehydration, constipation, fatigue/depression, muscle pain

regulators of blood calcium

parathyroid hormone

vitamin D

calcitonin

sites of calcium regulation

daily turn-over of bone calcium

plasma calcium

cytosolic calcium

bone - primary store

kidney - recover

intestine - absorption

daily turn-over of bone calcium

700 mg

plasma calcium

2.5 mmol/L

cytosolic calcium

100 nmol/L

bone

1 kg

kidney

recovers 99%

intestine

absorption - 10-20%

regulators

vitamin D

parathyroid hormone

calcitonin

vitamin D

increasing serum Ca by promoting Ca absorption in the gut

parathyroid hormone

bad for bone

increase serum Ca by stimulating recovery from kidney, calcium mobilization from bones, enhance Vit D effects

calcitonin

good for bone

decrease serum Ca by decreasing Ca recovery and inhibit mobilization from bone

drugs for Ca control and bone health

calcium

vitamin D

calcitonin

bisphosphonates

calcium as a drug

for hypocalcemia

osteoporosis

Vitamin D as a drug

for hypocalcemia

osteoporosis

Calcitonin as a drug

inhibit Ca mobilization from bone

reduce serum Ca

for hypercalcemia, Paget’s disease, osteoporosis

Bisphosphonates as a drug

inhibit Ca mobilization

decrease serum Ca

for osteoporosis, hypercalcemia