parathyroide hormone and bone disease
TRANSCRIPT
Parathyroid hormone
and bone diseases
By: Hosam abd alkadum
Out lines: CalciumCalcium absorptionDisorders of Parathyroid Hormone
calcium:
One of the most important elements found in the body.
Structural component in bone and teeth. . 99% stored in the bone The average content of calcium in adults is 1 kg
Calcium absorption: refers to the transport of the calcium that received from food, from intestine into the blood.
Substances that increased calcium in
blood:
1. active form of Vitamin D.
2. Parathyroid hormone.
1. Active form of vitamin D Found two types from vitamin D:
vitamin D2 (ergocalciferol) vitamin D3 ( cholecalciferol)
Found two sources for vitamin D in human body: From Diet. From Dermal synthesis of vitamin D from cholesterol is
dependent on sun light (specifically UVB radiation).
Vitamin D from the diet or dermal synthesis form's sun light is biologically inactive
activation requires enzymatic conversion (hydroxylation) in the liver and kidney and activation by parathyroid hormone.
The active form of vitamin D absorption calcium from intestine.
Activation
Of Vitamin
D
2. Parathyroid hormone
Parathyroid hormone (PTH) is a hormone secreted by the parathyroid glands.
increase of Calcium concentration in plasma by:
1.Activation of vitamin Dз synthesis and increase of absorption in the intestine
Effect PTH on Activation of vitamin D
2. Increase of calcium reabsorption in kidneys
3. Releasing of Са by bones (osteoclasts)
Disorders of Parathyroid Hormone
Hyperparathyroidism
Hypo parathyroidism
metabolic disorder with excessive secretion of Parathyroid hormone (PTH).
can be characterized into primary, secondary, and tertiary.
Resulting in high levels of calcium in the blood (hypercalcemia), which can cause a variety of health problems.
causing bone furcating and bone pain.
Hyperparathyroidism
deficiency or absence of PTH secretion.
metabolic disorder characterized by low serum calcium.
Causes decrease in effective vitamin D in body.
Hypo parathyroidism