Renal 1 & 2

Question 1

Renal Functions

Answer 1

• Excretion of metabolic waste and foreign substances
• Regulation of water and metabolite balance
• Regulation of extracellular fluid
• Regulation of plasma osmolality
• Regulation of red blood cell production
• Regulation of vascular resistance
• Regulation of acid-base balance
• Regulation of vitamin D production

Question 2

Inulin in relation to GFR

Answer 2

Clearance of inulin = Glomerular Filtration Rate (GFR)

Question 3

Key Characteristic of Inulin

Answer 3

neither reabsorbed or secreted by kidney

Question 4

What is renal clearance?

Answer 4

measurement to analyze of kidney

Question 5

Creatinine in relation to GFR

Answer 5

approximates GFR

Question 6

Key Characteristic of Creatinine

Answer 6

Freely filtered, 10% secreted

Question 7

How to detect lower GFR?

Answer 7

higher plasma Creatinine (or BUN)

Question 8

Which is a more reliable measure of GFR, creatinine or BUN?

Answer 8

Creatinine. It is created from muscle metabolism.

BUN increases after a high protein meal, which makes it less reliable due to it’s fluctuation

Question 9

What does clearance of PAH approximate?

Answer 9

Renal Plasma Flow (RPF)

Question 10

Characteristics of Proximal Tubule

Answer 10

-High volume, low-gradient reabsorption

Question 11

Characteristics of Loop of Henle

Answer 11

• Formation of high interstitial osmolality

- Descending and ascending thin limbs have poorly developed apical and basolateral surfaces

Question 12

Characteristics of Distal Tubule

Answer 12

low-volume, high-gradient reabsorption

Question 13

Macula Densa

Answer 13

• Juxtaglomerular Apparatus
• sensor of tubular flow
• well developed basolateral membrane and abundant mitochondria

Question 14

Characteristics of Collecting Duct

Answer 14

• Concentration/dilution of final urine

- composed of two cell types ( principal and intercalated)

Question 15

Principal cells

Answer 15

• moderately invaginated basolateral membrane and contain few mitochondria
• play an important role in reabsorption of NaCl and secretion of K+

Question 16

Intercalated cells

Answer 16

• important role in regulating acid-base balance and high density of mitochondria
• one population secretes H+ (reabsorbs HCO3-)
• second population secretes HCO3-

Question 17

Renal Blood Flow (RBF)

Answer 17

• 1200 mL/min

- 25% total cardiac output

Question 18

Renal Plasma Flow (RPF)

Answer 18

-660 mL/min

-

Question 19

Glomerular Filtration Rate (GFR)

Answer 19

125 mL/min

Question 20

Peritubular capillaries

Answer 20

• 90% RBF (cortical)

- reabsorption of water and solutes from renal cortex

Question 21

Vasa recta capillaries

Answer 21

• 10% RBF (8% outer medulla / 2% inner medulla

- reabsorption of water and solutes from renal medulla

Question 22

Prostaglandins

Answer 22

• renal vasodilation

- regulation of RPF and GRF