ANP 1107A Renal Lecture 3 March 8 Flashcards
What does ADH do to the collecting duct?
it acts at collecting ducts to increase number of water channels in principal cells
collecting ducts extend into
medullary area
- filtrate can again attain an osmolarity up to 1200 mOsm
what is facultative water reabsorption?
Water reabsorption that depends on the pressence of ADH. In the presence of ADH 99% of H20 in filtrate is reabsorbed.
what does it mean when levels of ADH are too low?
means that the kidneys are allowing more water to be excreted, which can lead to dehydration.
what happens when plasma osmolarity is above 300 mOsm?
increased levels of ADH to conserve body
- high levels of plasma osmolarity = conserve water to maintain a proper balance of fluids and electrolytes in the body
for example, what happens when plasma osmolarity is above 300 mOsm?
this happens when you’re sweating or not drinking enough water, it will trigger an increase in ADH to prevent dehydration.
What is a diuretic?
is any substance that is not reabsorbed
exceeds renal reabsorption: eg. someone with type 1 diabetes
what do caffeine and most prescribed diuretic drugs do?
inhibit Na+ reabsorption
what is the net effect of inhibiting Na+ reabsorption
haven’t pulled back as much Na
what is the renal clearance calculation
RC = UV/P
what is the U
substance mg/ml in urine
what is the V
flow rate of urine formation (ml/min)
what is the P
substance (mg/ml) in plasma
what is the colour/transparency of urine
clear/pale to deep yellow
what is urochrome
pigment from heme degradation
what does deepness of yellow indicate in urine?
not drinking enough water
-some drugs/vitamins can alter colour of urine
what can cloudiness in urine indicate?
bacteria infection
where does the odour of urine come from?
will develop ammonia odour if left to stand due to bacterial metabolism of urea
- drugs and vitamins can alter odour
pH of urine is usually?
6
but can vary ~4.5-~8)
what is acidic urine?
diet rich in protein and whole wheat
what is alkaline urine?
diet rich in vegetables
what is the chemical composition of urine?
95% water, 5% solutes
