Answer to the questions

1. Give other names for ADH.
Vasopressin; Arginine Vasopressin; AVP

2- 3. Two principal sites of action of AVP.
Kidney and Bloodvessels

4. A common disease related to ADH.
Diabetes Insipidus (DI)

5. Major sign of Diabetes Insipidus.
Excessive Urination

6- 7. Give the 2functions of AVP.
Regulates extracellular fluid volume and It is a vasoconstriction

8. Normal values for ADH test.
0 to 4.7 pg/mL

9. Give one condition if the result obtained is abnormally high.
Post- surgery fluid imbalance

10. Give one condition if the result obtained is abnormally low.
Diabetes Insipidus (central or nephrogenic)

Case Analysis:

11- 20. A 24-year old woman Liz, is a flight attendant for almost 5 years. One day when she was on leave she noticed that every hour she had to go to the bathroom and she felt uneasy about it. That was why she went to see a doctor but they didn't find any abnormality on physical examination.

What probable condition is Liz suffering from?

Liz is suffering from excessive urination or also known as polyuria which is a major sign of having Diabetes Insipidus.

This DI may arise from either of this two situations,

Hypothalamic DI this is deficiency in the secretion of ADH in the posterior pituitary and Nephrogenic DI this is when the kidney is unable to respond to ADH.

ADH is the hormone that decreases urine production and in this case there is the absence of ADH, that was why Liz is suffering from excessive urination.

What test would you recommend to diagnose her?

ADH test, because this test is performed if a disorder that affects ADH level is suspected.

Test. Test. Test.

Identification:

___________1. Give other names for ADH.
___________2- 3. Two Principal sites of action of AVP.
___________3.
___________4. Common diseases related to ADH.
___________5. A major sign of Diabetes Insipidus.
___________6- 7. Give the 2functions of AVP.
___________7.
___________8. Normal values for ADH test.
___________9. Give one condition if the result obtained is abnormally high.
___________10. Give one condition if the result obtained is abnormally low.


Case Analysis:

11- 20. A 24-year old woman Liz, is a flight attendant for almost 5 years. One day when she was on leave she noticed that every hour she hasdto go to the bathroom and she felt uneasy about it. That was why she went to see a doctor but they did not find any abnormalities on physical examination.

• What probable condition is Liz suffering from?
• What test would you recommend to diagnose her?

Vasopressin

ANTI DIURETIC HORMONE

Other name: Vasopressin; Arginine Vasopressin; AVP

ADH is a hormone secreted by the posterior lobe of the pituitary gland that constricts blood vessels, which is responsible in the rise of blood pressure , and reduces excretion of urine.

I will illustrate a simple diagram of ADH action in our body.

Posterior lobe --> anti diuretic (vasopressin) --> site of action for kidney --> reabsorption of water and fluid balance --> site of action for arterioles --> blood pressure

Anti diuretic hormone is a substance that decreases urine production. It causes the kidney to return more water to the blood, thus decreases the urine volume. Urine Output increases more than ten folds in the absence of ADH while in the presence of ADH, the kidneys retain water. ADH is produced by the hypothalamus and secreted by the posterior pituitary gland. Plasma osmolarity or concentration of solutes in blood, is the most important variable that regulates the anti diuretic hormone secretion. The plasma osmolarity is being sensed in the hypothalamus by neurons known as the osmoreceptors.

Two principle sites of action of AVP: kidney and bloodvessels.

Functions of AVP:
1. Regulates extracellular fluid volume
2. AVP is vasoconstriction.

Common disease related to ADH is Diabetes Insipidus. This condition may arise from either of two situations:
- Hypothalamic (central) diabetes insipidus- deficiency is the secretion of ADH from the posterior pituitary
- Nephrogenic diabetes insipidus- occurs when kidney is unable to respond to ADH

Major signs of either of the type of Diabetes Insipidus is: excessive urine production.

Test: ADH test
The test is performed if a disorder that affects the ADH level is suspected.
In some diseases, the normal release of ADH is altered, and the serum level of ADH must be tested to determine the cause. ADH may be measured as part of a "water restriction test" to more thoroughly investigate the cause of a disease.

Normal Values for ADH test:
Values of 0 to 4.7 pg/mL are normal.

Abnormally high may indicate:
-Acute porphyria (very rare)
-CNS infection
-CNS Tumor
-Post-surgery fluid imbalance
-SIADH (syndrome of inappropriate ADH)

Abnormally low may indicate:
-Damage to the pituitary gland
-Diabetes Insipidus (central or nephrogenic)
-Primary polydipsia


Reference:
http://www.cvphysiology.com/Blood%20Pressure/BP016.htm
http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/hypopit/adh.html
http://healthguide.howstuffworks.com/adh-dictionary.htm
http://www.ecosci.jp/pdb/vasopressin.gif
http://www.umm.edu/ency/article/003702.htm
Principles of Anatomy & Physiology, Gerard J. Tortora, Bryan Derrickson