1. 2 December 2011 Renal Physiology
Test # 3 Monday Dec 5th
Lab Next Week: Urinalysis
Options:
800 ml tap water
800 ml tap water + 7 g NaCl
80 ml tap water + 7 g NaCl
None of the above

2. Urinalysis Lab Day 800 ml tap water 800 ml tap water + 7 g NaCl
Drink Test Beverage
Drink plenty of water the day of lab;
Avoid coffee, caffeine, salty foods
60 min
30 min
30 min
30 min
30 min
30 min
1 Hr before Lab
Empty bladder; note time
At 30 min intervals, collect urine
measure V and [NaCl]
Beginning of Lab:
Collect Urine, measure Volume and titrate for [NaCl]

3. 1QQ 33 for 8:30
How does the composition of the ultrafiltrate in Bowman’s space differ from plasma? If glucose concentration in the plasma is 70 mg/ml, what will the glucose concentration be in the ultrafiltrate in Bowman’s space?
What is the location and role of macula densa cells?
Which segments of the nephron are found in the medulla?
What are two ways by which GFR can be increased?

4. 1QQ 33 for 9:30
How does the composition of the ultrafiltrate in Bowman’s space differ from plasma? If glucose concentration in the plasma is 100 mg/ml, what will the glucose concentration be in the ultrafiltrate in Bowman’s space?
What is the location and role of macula densa cells?
Which segments of the nephron are found in the medulla?
What are two ways by which GFR can be decreased?

6. Figure 14.10 reabsorption secretion
Membrane proteins are segregated into apical (luminal) and basolateral membranes.
Figure 14.10
reabsorption
secretion
Amino acid
glucose
metabolism

7. Filtration is controlled by aa and ea diameters!

8. Consider a substance that in filtered only, no reabsorption, no secretion.
Excretion of this substance = GFR
Clearance of this substance = GFR

9. Clearance = volume of plasma from which a substance is completely removed (cleared) by the kidneys per unit time.
Two substances that are only filtered: Inulin and Creatinine
Cinulin or Ccreatinine = Glomerular Filtration Rate
Clearance of Inulin is 120 ml/min

10. Renal Handling of Substances
Filtration + complete Secretion
Ex: Para AminoHippurate (PAH)
Measure Renal Plasma Flow
Filtration + partial reabsorption
Ex: Sodium Ex: Water
Filtration Reabsorption
Ex: Glucose Ex: Amino Acids

11. Clearance of Inulin is 120 ml/min
Clearance allows us to determine how the kidneys are handling a substance (net secretion or net reabsorption.)
Clearance of Inulin is 120 ml/min
Cinulin or Ccreatinine = Glomerular Filtration Rate
If C x is greater than GFR ( which is Cinulin) then that substance undergoes NET TUBULAR SECRETION
If C x is less than GFR ( which is Cinulin) then that substance undergoes NET TUBULAR REABSORPTION

12. Renal Handling of Substances
Filtration + complete Secretion
Ex: Para AminoHippurate (PAH)
Measure Renal Plasma Flow
Filtration + partial reabsorption
Ex: Sodium Ex: Water
Filtration Reabsorption
Ex: Glucose Ex: Amino Acids

13. A little more on Clearance:
Clearance of glucose = 0 ml/min which means….
Clearance of X = 120 ml/min which means….
Clearance of antibiotic XXX = 500 ml/min which means…

14. Calculating clearance
Clearance of s = Urine concentration of s X Urine Volume
Plasma concentration of s
“24 hour urine catch” + blood sample
Special cases: Clearance of
Inulin and creatinine (filtered only; use to measure Glomerular Filtration Rate.)
Para Amino Hippurate (filtered and completely secreted, use to measure Renal Plasma Flow)

15. Who Cares?

16. S 17
Sonogram showing
fluid-fill cavities within the kidney
Dr. Davis’s lovely bride of 30+ years

17. PKD is an autosomal dominant:
Fig
Fluid-filled cysts
PKD is an autosomal dominant:
pp X P?
Polycystic Kidney Disease
Symptoms? Genetics? Prognosis & Treament?
Measure Ccreatinine
To chart the progress of the disease.
14.04.jpg
End of Material for Test # 3

18. Reabsorption and secretion in proximal tubule is NOT under hormonal control.
Primary active transport of Na+ establishes a gradient for reabsorption of glucose, amino acids, etc.
Reabsorption and secretion in DCT & CD is under hormonal control.
Hormones that act here: ANH, ADH, Aldosterone.
Here, reabsorption of Na+ is linked to the secretion of K+.