Nephro 1

Question 1

Site of erythropoietin (EPO) production

Answer 1

Interstitial cells of the peritubular capillaries

Question 2

Active form of Vitamin D

Answer 2

1,25 dihydrocholecalciferol (Calcitriol)
1st hydroxylation happens in the LIVER (via 25-alpha hydroxylase)
2nd hydroxylation happens in the KIDNEY (via 1-alpha hydroxylase)

Question 3

Contains vasa recta, and has longer loops of Henle

Answer 3

Juxtamedullary nephrons (less common than cortical nephrons)

Question 4

Components of the Juxtaglomerular (JG) Apparatus

Answer 4

Macula densa (in the walls of the distal tubule; detects changes in BP
JG cells (in the walls of the afferent arteriole; secretes renin)
Lacis cells (unknown function)

Question 5

Physiologic function of renin

Answer 5

None (merely converts angiotensinogen from the liver to angiotensin I)

Question 6

Physiologic function of Angiotensin I

Answer 6

None (merely converted to angiotensin II due to ACE, in the lungs)

Question 7

Physiologic function of Angiotensin II

Answer 7

Vasconstricts afferent and efferent arterioles (efferent > afferent)
Systemic vasoconstriction
Stimulates thirst
Increases ADH, Cortisol, Epi, NE and Aldosterone

Question 8

Site of aldosterone production

Answer 8

Zona Glomerulosa of the Adrenal Cortex

Question 9

Aldosterone action

Answer 9

Increases Na+ reabsorption, K+ secretion, and H+ secretion

Question 10

ADH actions

Answer 10

Insertion of aquaporins/ water channels in the distal tubules and collecting ducts

Question 11

Triggers for ADH secretion

Answer 11

Increased plasma osmolarity
Decreased blood volume
Decreased blood pressure

Question 12

Afferent arteriolar vasodilation…

Answer 12

Increases GFR (inc. Glomerular capillary hydrostatic pressure)

Question 13

Afferent arteriolar vasoconstriction…

Answer 13

Decreases GFR (dec. Glomerular capillary hydrostatic pressure)

Question 14

Efferent arteriolar vasodilation…

Answer 14

Decreases GFR (dec. Glomerular capillary hydrostatic pressure)

Question 15

Moderate efferent arteriolar vasoconstriction

Answer 15

Increases GFR (inc. Glomerular capillary hydrostatic pressure)

Question 16

Severe efferent arteriolar vasoconstriction

Answer 16

Decreases GFR (Inc. Glomerular Capillary Oncotic Pressure, Donnan Effect)

Question 17

Albumin (negatively-charged) attracts positively-charged ions like sodium which then attracts water

Answer 17

Donnan Effect

Question 18

Absorb Na+ and H20 and secrete K+

Answer 18

Principal Cells

Question 19

Absorb K+ and Secrete H+

Answer 19

Intercalated Cells

Question 20

“Constant Load delivered to tubule”; mechanism for autoregulation of GFR

Answer 20

Tubuloglomerular Feedback

Question 21

“Percentage of Solute reabsorbed is held constant”; another mechanism of autoregulation for GFR

Answer 21

Glomerulotubular Balance

Question 22

Substances with no transport

Maximum and Renal Threshold (exhibits Gradient-Time Transport)

Answer 22

Sodium, and all passively transported solutes

Question 23

Ascending Limb of the Loop of Henle is permeable to..

Answer 23

Solutes (Mnemonic: ASINding Limb is permeable to solutes; impermeable to water)

Question 24

Descending Limb of the Loop of Henle is permeable to..

Answer 24

Water; impermeable to solutes

Question 25

Normal pH in various fluid sites

Answer 25

Arterial Blood: 7.40
Venous Blood, Interstitial Fluid: 7.35
Intracellular Fluid: 6.0-7.4
Urine: 4.5 - 8.0
Gastric HCl: 0.80
Vaginal secretions: 3.5-4.5

Question 26

Acid-Base Abnormalities caused by Diuretics

Answer 26

Metabolic Acidosis: Acetazolamide (Mnemonic: ACIDazolamide)

Metabolic Alkalosis: Loop Diuretics, Thiazide Diuretics

Question 27

Types of casts seen in various diseases

Answer 27

Hyaline cast: Ghost-like; no significance in the absence of proteinuria
RBC Cast: Nephritic Syndrome (e.g. Post-Strep GN)
WBC Cast: Acute Pyelonephritis, Acute Tubulo-Interstitial Nephritis
Renal Tubular Cell Cast/Granular Cast: Acute Tubular Necrosis (ATN)
Fatty Cast: Nephrotic syndrome
Waxy Cast: Chronic Renal Failure