Parathyroid and Adrenal Flashcards Preview

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Flashcards in Parathyroid and Adrenal Deck (20)
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1
Q

normal levels of calcium in blood

A

9-10 mg/dl

2
Q

Calcium distribution

A

40% combined with plasma proteins
10% bound to low-molecular weight substances (citrate or phosphate)
50% ionized

3
Q

Chief cells

A

Most numerous paranchymal cells of the parathyroid. They secrete PTH

4
Q

Oxyphil cells

A

These are a minor cell type in parathyroid glands.

They are not secretory and increase in number with age

5
Q

What is the relationship of Vitamin D and Calcium?

A

Vitamin D is important for the absorption of calcium from the intestinal tract

6
Q

This results when there is a decline in plasma calcium levels

A

Hypocalcemia

7
Q

Lethal if calcium levels fall below

A

4 mg/dl

8
Q

Hypercalcemia: when levels are approximately 12 mg/dl

A

Causes depression of nervous system, constipation and lack of appetite

9
Q

When levels are as high as 17 mg/dl, what happens to calcium phosphate crystals

A

Calcium phosphate crystals precipitate throughout the body

10
Q

Calcitonin

A

lowers serum calcium

11
Q

Function of PTH

A

Regulates calcium and phosphate levels in the blood:
Causes release of calcium and phosphate from the calcified bone matrix (bone resorption).
Reduces excretion of calcium by the kidneys.
Increases phosphate excretion by the kidneys.
Increases absorption of calcium from the intestine.

These effects cause blood calcium levels to increase but blood phosphate levels to decrease

12
Q

Hypoparathyroidism

A

This condition leads to inactivation of osteoclasts: calcium reabsorption is decreased leading to hypocalcemia

13
Q

Treatment for hypoparathyroidism

A

Vitamin D and its analogs

14
Q

Hyperparathyroidism

A

Usually due to a tumor of the parathyroid glands. Causes extreme osteoclastic activity in bones. In severe cases, bone may be entirely eaten away.

15
Q

Mild parathyroidism can cause formation of

A

Kidney stones

16
Q

Regulated by a simple feedback system. When calcium levels are low

A

PTH is secreted

17
Q

Treatment

Cinacalcet:

A

calcimimetic drug= reduces PTH secretion by influencing the parathyroid calcium sensing receptors

18
Q

Treatment of osteoporosis

A

Adequate intake of calcium and vitamin D
Bisphosphonates: alendronate, risedronate, ibandronate, zoledronic acid
PTH fragment: anabolic (bone building) compound when used intermittently
calcitonin: Inhibits osteoclasts and increases bone mass
Estrogen/Hormone Therapy (ET/HT)

19
Q

total loss of aldosterone

A

leads to death within 3 days to 2 weeks

20
Q

Hyperadrenalism (Cushing’s disease)

A

Caused by cortisol secreting tumor or hyperplasia of adrenal cortex due to increased secretion of ACTH