Urine Luck!

Renal slidesby

Dan CushmanDonations accepted and strongly encouraged

Renal pelvis

Renal vein

Cortex

Interlobar artery

Renalartery

divides intoanterior and

posterior branches.Medulla

Ureter

Lobe

Kidney parasiteParasitium nephrotium

(Just kidding, of course, it’s a nephron)

VesselsName the arteries of the kidney from largest to smallest

1. Renal Artery2. Interlobar artery

3. Arcuate artery4. Interlobular artery

5. Afferent arteriole6. Efferent arteriole

Kidney vessels Renalcorpuscles

Arcuate vessels

Interlobar vessels

Cortex

Medulla

Interlobular vessels

X10

Nephron segments

Cortex

Medulla

Proximal straight tubule

Distal convoluted tubule

Descending limb of HenleThin Ascending limb of Henle

Collecting duct

Proximal convoluted tubule

Thick Ascending limb of Henle

Renal corpuscle

Afferent arteriole

Efferentarteriole

(Layer)

Urinary pole

Parietal layer

(Layer)

Visceral layer

What is the best word in

nephrology?Corpuscle

What is the best structure in nephrology?

There really is not an answer to this question. It’s more of a personal reflection question with no objective answer. “Best” is hard to quantify.

Filtration apparatus

Capillary lumenSecondary

process(pedicel)

Glomerularbasement membrane

Endothelial cell nucleus

PodocytePrimaryprocess

(Glomerulus lumen)

Where are large anions repelled?

What is this?

Can’t you read?

Mesangial cells

Parietal layer

Visceral layer – PodocyteEfferent

arteriole

Afferentarteriole

What are the functions of mesangial cells?a. Phagocytic – clean the basement membrane,

ex. Remove immune complexes from the membrane.

b. Support – podocytes.c. They are contractile- can regulate glomerular

lumen.d. Secretory –  Interleukin-1 and platelet-derived

growth factor. These respond to glomerular injury.

Macula densa

Juxtaglomerular cells

Afferentarteriole

Distalconvolutedtubule

So… tell me about the juxtaglomerular cells.a. Smooth muscle cells of the afferent arteriole.

They are innervated by sympathetic neurons and secrete renin into the blood.

Which is which?Proximal Tubule

Distal Tubule

(Brush Border)

Which is which?Full Bladder

Empty Bladder

Neural tubeIntermediateMesoderm Paraxial

Mesoderm

Gut

Which portion turns into a kidney?What is its main

signaler?

Order these three chronologicallyMesonephric kidney Pronephric kidney

Metanephric kidney

Which one turns into your kidney?

Which one turns into the ductus

deferens?

Metanephros

Cloaca

Mesonephros tubules

Hindgut

Mesonephric duct

MetanephricMesoderm(blastema)

Uretericbud

What transcription factor do I create?

GDNFWhich induces what other factor?

WT1

Name the defect

Pelvic kidney

Bifidureter

Horseshoekidney

Where’s the bladder?

Here

Where’s the love?

All around us

NormalsProperty Value

Renal blood flow (mL/min) 1200

Renal plasma flow (mL/min) 660

GFR (mL/min) 125

Filtration fraction 0.20 – 0.25

Total body water (% of total body weight) 60%

ICFV (% of total body water) 60-67%

ECFV (% of total body water) 33-40%

Plasma volume (% of total body weight) 4%

Urine osmolarity (mosm/L) 500-800

Plasma osmolarity (mosm/L) 285

Substance Importance

PAH CPAH = ERPF

Inulin Cinulin = GFR

Creatinine Ccreatinine = GFR (overestimate)

Substances

Match each to a line

Filtered

Excreted

Secreted

Event Increase or decrease

Solute diuresis ↓

Reduced blood flow through vasa recta ↑

Inhibition of Na, K, 2 Cl cotransporter ↓

Washout of urea ↓

Increased number of JM nephrons ↑

Renal disease ↓

Will the hypertonic gradient in the medullary interstitium ↑ or ↓?

Match transporters with locationThick ascending

loop of Henle

Thin ascending loop of Henle

Proximal Tubule

Na/K/2 Cl symport

Descending loop of Henle Na/H antiport

Na/glucose symport

Na/HCO3 antiport

Proximal Tubule

Proximal Tubule

How do V2 receptors function?They are localized in the basolateral

membranes of principal cells. Activation of V2 receptors elevates

cyclic AMP in these cells, which leads to insertion of water-permeable channels

(AQP2) into the lumenal membrane.

What causes ADH release (6)?

• Increase in plasma osmolarity (1-2% threshold)

• Reduction in circulating blood volume (>10%) and blood pressure

• Angiotensin II• Stress (physical or emotional), pain• Nausea • Standing upright (→orthostatic antidiuresis)

H2O

H2O

What percentage is reabsorbed in each section?

65%65%

25%15%

Coupled with which anions?Na

Cl- (50% of its filtered amount) and HCO3

- (90%)

NaCoupled with which anions?Cl- (33% of its

filtered amount)

Where is the lower O2 content?

The medulla

The cortex

Rearrange these urea transporters to make a face.

Order these in terms of reaction speed

Baroreceptor reflex

Renal control of body NaCl

Angiotensin II Slow

Medium

Fast

Renal Regulation: High, Intermediate, or Low?

Intermediate HCO3-

Creatinine

Urea

Na+

Water

Ca2+

Low [Cr]P ↑ as nephrons are lost

Low

High

High

Intermediate

Match the lines

AlcoholGlucose or water

Saline

Which will have the greatest osmolarity?

Saline

↑/↓ ↑/↓

↑/↓

↑/↓ ↑/↓

↑/↓

↑/↓

↑/↓ ↑/↓ ↑/↓

↑/↓ ↑/↓ ↑/↓

↑/↓ ↑/↓ ↑/↓

Each caused by what?

↑ perfusion pressure, NE, (ATII)

ATII

ATII

What will increase FENa?

Dilation of efferent arterioleConstriction or Dilation

Decrease activation of RAA systemIncrease or Decrease

Increase secretion of natriuretic hormones

Increase or Decrease

↑/↓

↑/↓

↑/↓

↑/↓↑/↓

↑/↓

↑/↓

↑/↓ ↑/↓

AldosteroneDirect stimulants (2): ↑ [K+]plasma, ATII

Acts on (2):Late distal tubule,

collecting ductsPrincipal cells do what (4):

- Increased Na+ permeability of lumenal membrane- Increased K+ permeability of lumenal membrane- Increased lumenal Na+/H+ exchange- Increase in activity and number of basolateral Na+,K+-ATPase pumps

Intercalated cells do what (1):- Increased lumenal H+-ATPase activity

Most importantly, what happens to

FENa?

It decreases!

↑/↓

↑/↓

↑/↓ ↑/↓↑/↓

↑/↓

↑/↓

↑/↓

↑/↓

↑/↓↑/↓

↑/↓

↑/↓

Choose: Osmoregulation or Volume Regulation?

Osmoregulation Senses plasma osmolality

Regulates ADH, thirst

Affects urine Na excretion

Takes days to occur

Edema is a physical sign

ADH, ANP, RAA system

Osmoregulation

Volume Regulation

Volume Regulation

Volume Regulation

Volume Regulation

Volume Regulation

↑ ATII

↑ Renin

↑ Sympathetics

Baroreceptors(Sensor)

(hormone)

Name the three substances that increase the Na/K ATPase activity

1

1

2

2

2 3

Which side represents a reaction to a state of low K+?

What exchange occurs in principal cells?

What exchange occurs in intercalated cells?

Na+ in, K+ and H+ out

K+ in, H+ out

Property Inc/Dec

Low K+ diet ↓

High K+ permeability of lum. membrane ↑

Decreased fluid flow through lumen ↓

Increased intralumenal negativity ↑

High Na+ diet ↑

Metabolic alkalosis ↑

Aldosterone + high fluid flow rates ↑↑

Effect on K+ excretion

Property Inc/Dec

Decreased filtered load of HCO3- ↓

Increased arterial pCO2 ↑

Low angiotensin II ↓

Respiratory acidosis ↑

Decreased ECFV ↑

↑ Aldosterone ↑

Effect on HCO3- Reabsorption

Property Inc/Dec

K+ elevation ↓

Acute respiratory acidosis ↑

Metabolic acidosis ↑

Acidic urinary pH ↑

Effect on Ammonium Excretion

Property Inc/Dec

High pH ↓

Increased filtered load of phosphate ↑

Decreased PTH ↓

Effect on Titratable Acidity of Urine

↑/↓ ↑/↓↑/↓

↑/↓ ↑/↓

↑/↓ ↑/↓

↑/↓

Property Value

Increased K+ intake Hyperkalemia

Increased GI loss Hypokalemia

Excessive insulin administration Hypokalemia

Renal failure Hyperkalemia

Untreated diabetes mellitus Hyperkalemia

Treatment with thiazides/L-A diuretics Hypokalemia

Primary hyperaldosterism Hypokalemia

This patient is treated with ACE inhibitors Hypokalemia

Treated with calcium chloride infusion Hyperkalemia

Treated with adrenergic agonist Hyperkalemia

Hyper- or Hypokalemia?

Name the drugs

B (3 drugs)A

Identify the

followingMetabolic alkalosis

Chronic respiratory acidosis

Chronic respiratory alkalosis

Acute respiratory acidosis

Effect (Plasma)

Cause (high)

[Na] pH [K] [Ca] [Mg] Pi HCO3 ADH Aldost Met Ac Met Alk

[Na] ↓ ↑ ↑/↓ ↓ ↑

pH ↓

[K] ↑ ↓ ↑

[Ca] ↑ ↓

[Mg]

Pi ↓

HCO3 ↓

ADH

Aldost ↑ ↑ ↓ ↑

Met Ac ↓ ↑ ↑ ↓

Met Alk ↑ ↓ ↓ ↑

Resp Ac ↓ ↑ ↓

Resp Alk ↑ ↓ ↓ ↑

PTH ↑ ↑ ↓

ANP ↓ ↓ ↓

↑/↓ ↑/↓ ↑/↓ ↑/↓ ↑/↓↑/↓

↑/↓ ↑/↓ ↑/↓

↑/↓ ↑/↓

↑/↓↑/↓

↑/↓ ↑/↓ ↑/↓ ↑/↓

↑/↓ ↑/↓ ↑/↓ ↑/↓↑/↓ ↑/↓ ↑/↓ ↑/↓↑/↓ ↑/↓ ↑/↓↑/↓ ↑/↓ ↑/↓ ↑/↓

↑/↓ ↑/↓ ↑/↓↑/↓ ↑/↓ ↑/↓

And now…

Kay’s slides

Everything wrong was her fault

Is Na+ reabsorbed or secreted in the proximal convoluted tubule?Reabsorbed!

By what mechanism is it reabsorbed?

By a wide variety of Na+-linked lumenal transporters and solvent drag.

Is Na+ reabsorbed or secreted in the thin descending limb of the loop of Henle?

Neither! For the most part, the thin descending limb only reabsorbs water.

XIs Na+ reabsorbed or secreted in the thin ascending limb of the loop of Henle?Passively reabsorbed.

Is Na+ reabsorbed or secreted in the thick ascending limb of the loop of Henle?

Reabsorbed via the Na+, K+, 2Cl- co-transporter. Known as the medullary diluting segment.

Is Na+ reabsorbed or secreted in the first 2/3 of the distal convoluted tubule?

Actively reabsorbed. Known as the cortical diluting segment.

And finally, what about the late distal convoluted tubule and the collecting duct?

What diuretics work here?

Loop-acting diuretics.

What diuretics work here?

Thiazides.

What diuretics work here?

K+-sparing diuretics.

Reabsorption occurs and is stimulated by aldosterone.

What diuretics work here?

Carbonic Anhydrase Inhibitors

In the proximal tubule, are the following secreted or reabsorbed?

Water: Reabsorbed % of filtered:65%Urea: Reabsorbed (50%)

K+: Reabsorbed (67%) Ca2+: Reabsorbed (67%)

Pi: Reabsorbed (majority)

What is reabsorbed in the thin descending limb of the loop of Henle?Mainly just water!

Mg2+: No movement

In the thin ascending limb of the loop of Henle, what is reabsorbed?

Na+, Cl-

What is secreted?Urea (60%-110%)

In the thick ascending limb of the loop of Henle, what is reabsorbed?

Na+, K+, Cl-, Ca2+, Mg2+

What happens in the first 2/3 of the distal convoluted tubule?• ALWAYS impermeable to water• Reabsorbs Na+

• Called the cortical diluting segment

What happens in the last 1/3 of the distal convoluted tubule?• Absorbs water ONLY when ADH

is present• Can reabsorb Na+ against a

large electrochemical gradient

Distal tubule in general also reabsorbs Ca2+ and a little bit of Mg2+

What about K+?K is actively reabsorbed by intercalated cells & passively secreted by principal cells

Finally, we come to the collecting duct:

Na+:Urea:

K+:

Water:

Mg2+:

Pi:

Ca2+:

Reabsorbed (40% to 70%)(only in the medullary region)

Reabsorbed (only w/ ADH)

Reabsorbed

Reabsorbed or secreted

No movement

No movementNo movement