Regulation of ECF Volume and NaCl Balance Flashcards
1
Q
- High ADH can do what to sodium levels?
A
Can cause hyponatremia
2
Q
- When ADH is always high, _ is no longer controlled by ADH
- _ is then controlled by amount of free water you take in
A
Sodium
Sodium
3
Q
Urine should be _ in hyponatremia
A
diluted
4
Q
- How do you distinguish if the kidneys are responding appropriately to hyponatremia?**
A
- Urine is diluted
- Kidneys are responding appropriately
- ADH levels are low (where they should be)
- Problem is outside of the kidneys
5
Q
- Maintaining _ balance is important for long-term regulation of ECF volume
- Maintaining _ balance is important for regulating ECF osmolarity
A
Salt
Water
6
Q
- ECV (Effective Circulating Volume)
A
- Portion of the ECG volume that is in the arterial system ubder particular pressure and is effectively perfusing the tissues
- Not a measurable and distinct body fluid compartment
7
Q
How much of the vascular volume forms the ECV?
A
- 0.7 L (20% plasma, 5% of ECF, 1.7% TBW, 1% of body weight)
8
Q
- How is effective circulative volume changed in a person with congestive heart failure?
- How is this counteracted
A
- CHF patients have a low effective circulating volume (d/t decreased cardiac output)
- 4 Ways this is counteracted
- 1) Activation of RAAS system
- 2) Stimulation of sympathtetic nervous system via baroreceptor reflex
- 3) Increased ADH secretion
- 4) Increaed renal fluid retention via altered Starling’s forces in the peritubular capillaries
9
Q
- How is ECF volume changed in a person with CHF?
A
- Increased (Na+ and fluid retention-edema)
10
Q
- Where are osmoreceptors located?
- What do they respond to?
- How do they respond?
He included this twice, so probably will be on the test
A
- Supraoptic and paraventricular areas of the hypothalamus
- Changes in plasma osmolarity
- Respond in two ways:
- Regulate ADH release
- Regulate thirst
11
Q
- ADH secretion is controlled by what two receptors?
- Which is more sensitive?
A
- Osmoreceptors, barorecceptors
- Osmoreceptors
12
Q
Most important non-osmotic stimulus of ADH release
A
Decrease in sensed body volume/Decline in blood pressure (20% or greater)
13
Q
- With volume expansion, secretion of ADH is _
- With volume contraction, secretion of ADH is _
A
- Decreased
- Increased
14
Q
- _ baroreceptors have an important influence on the hypothalamus and secretion of ADH
- _ baroreceptors have major role in RAAS pathway
A
- Cardiopulmonary (in cardiac atria and pulmonary arteries)
- Intrarenal
15
Q
Identify the following types of baroreceptors
A
- Arterial
- Cardiopulmonary
- Intrarenal