RAAS Flashcards
Where is aldosterone produced?
the adrenal cortex
what type of hormone is aldosterone?
steroid
What is the function of aldosterone ?
Stimulates Na+ reabsorption in the distal tubules and collecting ducts
What stimulates aldosterone release?
angiotensin II
What does angiotensin II stimulate the release of from the adrenal cortex?
aldosterone
How is angiotensin II formed from angiotensin I?
angiotensin-converting enzyme
What is the function of angiotensin-converting enzyme ?
converts angiotensin I to angiotensin II
What splits angiotensin I from angiotensiogen?
renin
Why is aldosterone slower acting than vasopressin?
aldosterone is a steriod and vasopressin is a peptide
Describe aldosterone levels in a person who eats a high sodium diet?
low aldosterone levels
Which cells secrete renin?
juxtaglomerular cells
Where is angiotensin I converted into angiotensin II?
the lungs
How many litres of water are in a 70Kg male?
42L
What percentage of body weight is total body water?
60%
What percentage of total body weight is intracellular fluid?
40%
What percentage of total body weight is extracellular fluid ?
20%
What would the osmolality of pure water be?
0
What is osmolality ?
total number of particles in solution
What does isotonic mean?
the same osmolality
What is osmolarity?
the number of particles in 1 L of fluid
What is the main contributor to extracellular fluid osmolality?
sodium
What is the average urine volume per day?
1.5L
What is hypernatraemia?
high sodium
What is the major cation of the extracellular fluid?
sodium
What is the major cation of the intracellular fluid?
potassium
Which out of the ICF and ECF has more sodium?
ECF
Which organ produces angiotensinogen?
the liver
How does angiotensin II affect ADH secretion?
increases ADH secretion
What effect does angiotensin II have in blood vessels?
vasoconstriction
