Lecture #31: Renal Histolgy II

Question 1

What type of epithelium is found in the thin segment of the loop of Henle?

Answer 1

Simple Squamous Epithelium

Question 2

Do the cells of the thick ascending limb have a brush border?

Answer 2

NO

Question 3

Which limb, ascending or descending, of the loop of Henle is impermeable to water?

Answer 3

The ascending lib is impermeable to water.

Question 4

What is the descending thin limb of the loop of Henle permeable to?

Answer 4

Descending thin limb is permeable to water and sodium and chloride ions.

Question 5

True or False:

The ascending thin limb is impermeable to water and actively pumps chloride ion out of the tubule, allowing sodium ions to follow.

Answer 5

True

Question 6

What is the major function of the loop of Henle?

Answer 6

To establish the counter-current exchange system which creates the osmotic conditions necessary to pull water out of the distal convoluted tubule and collecting duct in the presence of ADH.

Question 7

What kind of epithelium lines the distal convoluted tubule?

Answer 7

Lined with simple cuboidal epithelium with smaller cells than those of the proximal convoluted tubule.

Question 8

Compare the lumen of the distal convoluted tubule and the proximal convoluted tubule.

Answer 8

The lumen of the distal convoluted tubule is larger than that of the proximal convoluted tubule and there is no brush border.

Question 9

Is the cytoplasm of the distal convoluted tubule less eosinophilic than that of the proximal convoluted tubule?

Answer 9

Yes

Question 10

The distal convoluted tubule is impermeable to water, except in the presence of what hormone?

Answer 10

ADH

Question 11

Where is antidiuretic hormone derived from?

Answer 11

Derived from the posterior pituitary.

Question 12

What does ADH function to do?

Answer 12

Functions to reduce water loss.

Question 13

What is antidiuretic hormone also known as?

Answer 13

vasopressin

Question 14

Look at figure 14-14

Answer 14

It will help show you how to determine between the PCT and DCT.

Question 15

What do principal cells do?

Answer 15

Reabsorb sodium ions and water and secrete potassium via ATPase pump.

Question 16

What do intercalated cells secrete?

Answer 16

Secrete either hydrogen or bicarbonate ion

Question 17

True or False:

The collecting duct has a different embryological origin than that of the nephron.

Answer 17

True

Question 18

What kind of epithelium is found in the thick segments of the loop of Henle?

Answer 18

Simple Low Cuboidal Epithelium

Question 19

What kind of epithelium does the wall of the collecting duct consist of?

Answer 19

Simple Cuboidal Epithelium

Question 20

What two types of specialized cell types are associated with the collecting duct?

Answer 20

> principal cells

> intercalated cells

Question 21

What are the layers that make up the renal pelvis, ureter, and urinary bladder, starting at the mucosa and going out to the adventitia?

Answer 21

Mucosa

Submucosa (not clearly demarcated)

Muscularis

Adventitia (FECT external to muscularis; serosa over superior surface of bladder).

Question 22

What does the mucosa of the renal pelvis, ureter, and urinary bladder consists of?

Answer 22

> transitional epithelium (urothelium)
> basement membrane
> lamina propria of FECT
> some loose lymphoid tissue
> a few smooth muscle cells

Question 23

Does the lower or upper third of the ureter have a third external longitudinal muscle coat?

Answer 23

Lower Third

Question 24

Other than in the lower third of the ureter, what does the muscularis layers consist of that make up the rest of the ureter?

Answer 24

inner longitudinal and outer circular smooth muscle coat in ureter.

Question 25

What do the layers of smooth muscle in the urinary bladder form?

Answer 25

Detrusor Muscle

Question 26

What kind of epithelium lines the mucosa of the prostatic urethra?

Answer 26

Transitional Epithelium

Question 27

True or False: The prostatic urethra is lightly vascularized with veins that have abundant elastic tissue in them.

Answer 27

False - prostatic urethra is highly vascularized with veins that have abundant elastic tissue in them.

Question 28

What type of epithelium lines the membranous urethra?

Answer 28

Tall pseudostratified columnar cells (but variable)

Question 29

True or False: The membranous urethra extends through the urogenital diaphragm and receives striated muscle cells forming the external sphincter of the bladder.

Answer 29

True

Question 30

What type of epithelium lines the cavernous urethra?

Answer 30

Lined with pseudostratified epithelium with patches of stratified squamous epithelium.

Question 31

What are the two types of glands that are found in the male urethra?

Answer 31

> Lucanae of Morgagni are invaginations of mucous membrane containing single or groups of intraepithelial mucous cells. > Glands of Littre are branched tubulara glands opening into the lacunae of Morgagni

Question 32

What type of epithelium is the mucosa of the female urethra primarily lined with?

Answer 32

Stratified or pseudostratified columnar epithelium with intraepithelial nests of mucous glands.

Question 33

True or False: The lamina propria of the female urethra is highly vascularized with veins with an abundance of elastic tissue.

Answer 33

True

Question 34

True or False: The submucosa and adventitia of the female urethra is not discernible on micrograph.

Answer 34

True

Question 35

Which layers of the female urethra muscularis layer are longitudinal and which one is circular?

Answer 35

Inner longitudinal and an outer circular layer of smooth muscle cells, but they're not well defined.

Question 36

List the functions of angiotensin II.

Answer 36

> Stimulates secretion of aldosterone from adrenal cortex > Aldosterone acts on the principal cells of the collecting ducts and the thick ascending limbs of Henle > Increases reabsorption of sodium ion and water which increases blood pressure > Stimulates release of ADH

Question 37

Where is ACE (angiotensin-converting factor from?

Answer 37

Pulmonary and Renal Endothelium

Question 38

Where is angiotensinogen from, and where is it found?

Answer 38

Circulating blood protein from the liver.

Question 39

Where is angiotensin I primarily produced?

Answer 39

Lungs

Question 40

What converts angiotensionogen to angiotensin I?

Answer 40

Renin

Question 41

What converts angiotensin I to angiotensin II?

Answer 41

ACE

Question 42

What factors stimulate the tubuloglomerular feedback system to trigger the renin-angiotensin-aldosterone system?

Answer 42

1) a depletion of the extracellular fluid compartment 2) a decrease in renal blood pressure (hypotension) 3) a decrease in [Na] (sodium) at the macula densa

Question 43

What does angiotensin II stimulate?

Answer 43

1) aldosterone secretion by adrenal cortex 2) arteriolar vasoconstriction (increases bp) 3) ADH secretion and thirst 4) reabsorption of NaCl by the proximal convoluted tubule

Question 44

What does aldosterone do?

Answer 44

Secreted by the adrenal cortex -> it reduces the excretion of NaCl by stimulating its reabsorption by the thick ascending limb of the loop of Henle, the distal convoluted tubule, and the collecting tubule.

Question 45

What does the afferent arteriole behave as?

Answer 45

Pressure Receptor **when blood pressure is reduced, the secretion of renin is stimulated.