Renal physio Intro

Question 1

What are the endocrine functions of the kidney?

Answer 1

Release of:

• Calcitriol
• erythropoietin
• Renin
• Renalase

Question 2

What is the function of Calcitriol?

Answer 2

Regulation of blood Ca++ and Phoshate; Increase intestinal absorption of Ca+/HPO4-2

Question 3

What is the function of erythropoietin? Related pathology?

Answer 3

Regulation on RBS production:

• Promotes maturation
• Stimulated by Low PO2 (Hypoxia)
• Chronic renal disease —> erythropoietin insufficiency

Question 4

What is the function of Renaolase?

Answer 4

Breakdown of blood catecholamines

Question 5

What is the renal papilla?

Answer 5

The narrowed region of the renal pyramid

Question 6

Which region do kidney stones typically form?

Answer 6

Renal papilla

Question 7

What is postrenal azotemia?

Answer 7

Accumulation of nitrogenous waste

Question 8

How does blood flow rate differ in the cortex vs medulla.

Answer 8

Cortex: High flow rate

Medulla: Slow flow rate

Question 9

When does tubular fluid become urine?

Answer 9

When several collecting ducts form a papillary duct.

Question 10

Differentiate Cortical vs Juxtamedullary nephrons.

Answer 10

Corticol:

• 85% of nephrons
• Short LOH
• Glomerulus in outer cortex
• Only thick ascending limb

JM:

• Glom next to medulla
• Thin and thick ascending limb
• Long LOH extending into Inner medulla
• ** Water conservation

Question 11

What is the osmolarty of cortical renal tissue? Medulla?

Answer 11

290 mOsM

Medulla: 1200 mOsM

Question 12

What is the site for reabsorption of substances into the blood from the filtrate?

Answer 12

Peritubular capillaries

Question 13

What is the Vasa Recta?

Answer 13

Specialized peritubular capillary network which surrounds the collecting ducts and limbs of Henle in JM nephrons

Question 14

How is Excretion calculated?

Answer 14

E = F + S - R

Question 15

How much plasma volume is Filteres? Excreted?

Answer 15

20% filtered

<1% excreted

Question 16

How much total body water is in skeletal muscle?

Answer 16

75% ICF or ~ 40-50% TBW

Question 17

What is Renal Plasma clearance?

Answer 17

Volume of plasma cleared from a substance in a unit of time,rate of elimination of a substance f/ vascular system by kidney

RPC = F + S - R

Question 18

What is the path of urine drainage from the collecting duct once formed?

Answer 18

Collecting duct — > Papillary duct —> Minor/major Calices —> Renal Pelvis —> Ureter

Question 19

What are Mesangial cells?

Answer 19

Immunoreactive transformed smooth muscle cells btwn glom capillaries which can contract in response to vasoactive substances impeding blood flow and filtration

Question 20

Where are JG cells located?

Answer 20

Junction of the glomerulus and transition of thick ascending LOH into distal tubule

Question 21

What is

A) TBW
B) ICF
C) ECF
D) ISF
E) TCF
F) PV in BV
G) PV

Answer 21

TBW: 42 L (70 Kg)

ICF (2/3): 28 L

ECF (1/3): 14 L

ISF (3/4 ECF): 10.5 L

PV (1/4 ECF): 3.5 L

TCV: 1 L

PV in BV: 55%

Question 22

What Ions are high in:

ECF
ICF
RBC
TCF

Answer 22

ECF: Na, Cl, HCO3

ICF: K, HPO4, A-

RBC: K, HCO3, Cl-, A-

TCF: H+, Cl-

Question 23

What are absorption’s for:

H2O
Na
HCO3
Glucose
Urea
K
HPO4

Answer 23

H2O; 99%
Na: 99.5%
HCO3: 99%
Glucose: 100%
Urea: 50%
K: 86%
Phosphate: 88%