Renal Physiology Flashcards Preview

Anatomy / Physio II > Renal Physiology > Flashcards

Flashcards in Renal Physiology Deck (45)
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1
Q

What is Wilm’s tumor?

A

A tumor of the kidney found in childhoood that is associated with aniridia and related ocular complications

2
Q

How many Wilm’s tumor cases occur in the US annually?

A

500

3
Q

How do the kidneys regulate osmotic pressure?

A

Excreting dilute or concentrated urine

4
Q

The kidneys regulate what molecules?

A

Na, K, Ca, Mg, Cl, HCO3, PO4, and SO4

5
Q

What do the kidneys eliminate from the system?

A

waste products - urea, uric acid, creatinine

Drugs and toxins

6
Q

The kidneys produce ______ and vitamin _

A

Erythropoietin and Vitamin D3

7
Q

The kidneys degrade ____ and ___

A

insulin and PTH

8
Q

The kidneys help regulate the acid/base balance by synthesizing _______

A

ammonia

9
Q

How do the kidneys regulate extracellular fluid?

A

By controlling Na and water excretion

10
Q

The kidneys adjust blood pressure by regulating __ excretion and producing ____

A

regulating Na excretion

producing renin

11
Q

The kidneys synthesize ____ and _____ which affect renal blood flow and Na excretion

A

Prostaglandins and kallikreins

12
Q

Total body water makes up __% of body weight

A

60%

13
Q

In regards to body fluid, the intracellular compartment makes up __% of body weight while the extracellular compartment make up __%

A

intracellular - 40%

extracellular - 20%

14
Q

What are the major electrolyte cations?

A

Na, K, Ca, Mg

15
Q

What are the major electrolye anions?

A

Cl, HCO3, PO4, SO4

16
Q

What does the macula densa of distal convoluted tubule do?

A

monitors composition of fluid in the tubular lumen

17
Q

What do the extraglomerular mesangial cells do?

A

Transmit information from macula densa to granular cells

18
Q

What is another name for the extraglomerular mesangial clles?

A

Lacis cells

19
Q

What do the granular cells do?

A

Synthesize renin

20
Q

What are granular cells made of? Where are they located?

A

Modified smooth muscle cells with epithelioid appearance located in afferent arteriole close to glomerulus

21
Q

The JG (granular) cells secrete renin in response to what?

A
  1. Beta-1 adrenergic stimulation
  2. Reduced renal perfusion pressure
  3. Decreased NaCl reabsorption by the macula densa
22
Q

Reduced renal perfusion pressure is detected directly by _____

A

JG cells

23
Q

NaCl reabsorption by the macula densa is due to _____

A

reduction in glomerular filtration rate (GFR)

24
Q

Excreted = ____ - ____ + ____

A

Excreted = filtered - reabsorbed + secreted

25
Q

The clearance of substrate is equal to what?

A

[(Urine concentration of substance) x (urine flow rate)] / (plasma concentration of substance)

26
Q

What is the glomerular filtration rate (GFR)?

A

Rate at which plasma is filtered by the glomeruli

27
Q

Inulin clearance is the same thing as what?

A

the Glomerular filtration rate

28
Q

What are the normal values of the Glomerular filtration rate?

A

110 - 125 mL/min

29
Q

What fructose polymer is used to measure GFR?

A

inulin

30
Q

Why is inulin ideal to measure GFR?

A
  1. Freely filterable by glomeruli
  2. Not reabsorbed or secreted by tubules
  3. Not synthesized, destroyed, or stored in kidneys
  4. Nontoxic
  5. Concentration in plasma and urine determined by simple analysis
31
Q

A clearance ratio of >1 indicates what?

A

Secretion

32
Q

A clearance ration of <1 indicates what?

A

Reabsorption

33
Q

Creatinine is a derivative of what substance?

A

creatine phosphate

34
Q

Why is the relationship between GFR and plasma creatinine inversely related?

A

the kidneys continuously clear creatinine from the plasma

35
Q

Creatinine adds __% to urinary values

A

20%

36
Q

What is the glucose threshold in urine?

A

200 mg%

37
Q

What two mechanisms do the kidneys use to autoregulate renal blood flow?

A

Myogenic mechanism

Tubuloglomerular feedback mechanism

38
Q

Is there more renal blood flow in the cortex or the medulla?

A

cortex

39
Q

How many liters per minute flow through the renal system?

A

1.2L / min

40
Q

What are the five major vasoconstrictors related to renal blood flow?

A
Adenosine
Angiotensin II
Endothelin
Thromboxane
Vasopressin
41
Q

What are the six major vasodilators related to renal blood flow?

A
Atrial natriuretic factor
Dopamine
Histamine
Kinins
NO
Prostaglandins
42
Q

How does the Myogenic mechanism help autoregulate blood flow?

A

Increased pressure stretches vessels and opens cationic channels resulting in depolarization and calcium influx

43
Q

How does the tubuloglomerular feedback mechanism help autoregulate blood flow?

A

Increased pressure increases GFR -> increases NaCl reabsorption and ATP release from macula densa.

44
Q

What do the negative ions in the barrier of the Glomerulus do?

A

Restrict the filtration of negatively charged compounds such as albumin

45
Q

What is the driving force for reabsorption of solutes and water in the proximal convoluted tubule?

A

Na reabsorption by Na / K ATPase