Renal water balance and diuretics Flashcards
1
Q
True/False - Water balance and salt balance work in tandem and are controlled together.
A
False - Water and salt balance are controlled independently of each other
2
Q
If total body water decreases, what happens to the extracellular fluid volume and blood pressure?
A
- Extracellular fluid volume decreases
- blood pressure decreases
3
Q
What is ADH?
A
- Also called Vasopressin
- made in hypothalamus
- stored in pituitary
- peptide hormone
- released due to high plasma osmolarity or low extracellular fluid volume
- causes kidney to filter less water, so less water is excreted
4
Q
What receptors signal for ADH release?
A
Osmoreceptors (in hypothalamus) - senses increase in osmolarity in blood, so sends signal to release ADH
Baroreceptors - decrease in blood pressure leads to less action potentials being sent to hypothalamus - causes ADH to be released
5
Q
What does ADH actually do?
A
- increases number of aquaporin ll channels on membrane of collecting duct
- more water reabsorbed in collecting duct
6
Q
What is diuresis?
A
- increased production of urine
7
Q
What is natriuresis?
A
- increased excretion of sodium
8
Q
What is diabetes insipidus?
A
- failure to release ADH (neurogenic) or failure of collecting duct cells to respond to ADH (nephrogenic)
9
Q
What do diuretics do?
A
- inhibit ADH from binding to receptors (V2 receptors)
- V2 receptor antagonists
