Lecture 15 Flashcards
What is the full name for ADH
anti-diuretic hormone
Filtrate at the top of ascending limb is _____
dilute
Why is the filtrate at the top of the ascending limb dilute
due to salt removal
What type of urine is produced in the abscence of ADH
very dilute urine
What is the function of adh
to make the body retain water
what happens to the collecting ducts in the absence of ADH
they become impermeable to water
Where is ADH released from
Posterior pituitary
Where does ADH act upon
Collecting ducts
What does adh do to principal cells
Increases number of water channels in these cells
Urea contributes to the _____ gradient
Osmotic
How does urea help in the interstitial space
It allows for a higher osmolarity, to draw water out of the nephron loop
What is a diuretic
Something that enhances urinary output
How does alcohol affect urine formation
It inhibits release of ADH - you wont be able to concentrate your urine
What is the formula for renal clearance
RC=UV/P
Describe clearance
Volume of blood cleaned of a substance/min
When would clearance be equal to GFR
Freely filtered
Not secreted or reabsorbed
What does the U stand for in RC
concentration of substance in urine (mg/mL)
What does the V stand for in RC
flow rate of urine formation (mL/min)
What does the P stand for in RC
The concentration of substance in the blood plasma (mg/mL)
What polysaccharide is used as a standard for RC
inulin
What is inulin
A polysaccharide used for RC standard
What if RC (substance) < RC (inulin)? eg: urea: RC = 70 ml/min
You arent removing all the urea from the 125mL of plasma, you’re reabsorbing some
What if RC (substance) = 0?
You’re reabsorbing all of the substance
What if RC (substance) > RC (inulin)? eg: creatinine: RC = 140 ml/min
We’re secreting extra of the substance
