Renal Histology and Anatomy

Question 1

the area where the renal artery enters, and where the renal vein and ureter exits, is called…

Answer 1

hilum

Question 2

size of a normal kidney?

Answer 2

11cm length

Question 3

average adult kidney weight?

Answer 3

female 135g

male 150g

Question 4

what is the peritoneal relationship of the kidneys?

Answer 4

retroperitoneal organs

Question 5

superior and inferior borders of the kidney?

Answer 5

cranial: superior border of T12 vertebra
caudal: level with L3 vertebra

Question 6

important vascular relationship of l kidney?

Answer 6

L gonadal artery and vein drain through it

Question 7

From what direction is it easiest to approach the kidneys? Why?

Answer 7

Posterior - lower 2/3 covered by muscle, adipose tissue – makes them susceptible to injury (e.g.blunt trauma) but also provides better approach for percutaneous biopsy

Question 8

Describe the blood supply to the kidney

Answer 8

Question 9

Three parts of the ureter?

Answer 9

Fibrous, muscular, mucous

Question 10

Where do the ureters open in to the bladder?

Answer 10

Lateral angles of the trigone

Question 11

Answer 11

Question 12

What is a medullary ray?

Answer 12

Parallel configuration of tubules (half a dozen or so)

Defines a lobule (glomeruli & all associated tubules that drain into collecting ducts and are portions of a medullary ray)

Medullary ray sits in CENTER of lobule; glomeruli are at BORDERS in rows

Vasculature (arteries, veins) run PARALLEL to medullary rays w/large lumen located at MR periphery

Question 13

What portions of nephrons are in the medullary rays?

Answer 13

Parallel portions of tubules (NO convoluted portions)

• Thick descending limb
• Thick ascending limb
• Collecting Duct

Question 14

Answer 14

Question 15

What kind of tubular cell is this?

Answer 15

Proximal tubule cell

Question 16

4?

Answer 16

Distal tubule

Question 17

s 1, 2?

Answer 17

Proximal tubules

Question 18

6?

Answer 18

Brush border of PT cells

Question 19

Outer medulla contains what?

Answer 19

Thick ascending limbs

Loops of Henle

Collecting ducts

Question 20

Inner medulla contains what?

Answer 20

Loops of Henle

Collecting ducts

More interstitium than outer medulla

Question 21

Difference between cortical and juxtamedullary nephrons?

Answer 21

Juxtamedullary nephrons have long loops of Henle

Important similarity: thick ascending limb forms at the junction of the inner and outer medulla for BOTH types of nephrons (this defines the division between the two zones)

Question 22

Answer 22

Question 23

What structure is this?

What type of tissue makes up the red, green, and blue circles?

Answer 23

This is the ureter.

• Red circle: lamina propria (loose connective tissue)
• Blue circle: smooth muscle (unlike GI tract, not organized into discrete layers - rather, SMC bundles run in all directions)
• Green circle: transitional (urothelial) epithelium

Question 24

Here are two bladder slices, at the same magnification.

• Which is more distended?
• What’s in the red rectangle at left? (same as the area immediately adjacent to it)

Answer 24

• The bladder on the RIGHT is more distended (thinner mucosa = more stretched)
• Red rectangle: SMCs in small fasicles in many different orientations (not discrete, circular longitudinal layers)

Question 25

This is the first part of the male urethra (the prostatic urethra). 1. What is the vascular structure within the light blue ellipse called? 2. The periurethral mucosa is in the green ellipse. It transitions from _______ to ______ epithelium.

Answer 25

1. Corpus spongiosus (muscular cavernous blood vessels that can distend to contribute to erection) 2. Transitional, squamous

Question 26

This is the female urethra. 1. What type of epithelium lines the urethra at the bladder end? Closer to the external meatus? 2. What is contained within the black circle? 3. What prominent structure is in the blue circle?

Answer 26

1. Transitional (bladder end), squamous (external meatus end) 2. Glands 3. Surrounding smooth muscle, which serves a sphincter role

Question 27

EM from glomerulus 1. What type of endothelial cells are found here? 2. Podocytes constitute the ______ layer of Bowman's space 3. What type of cell is found in the core of Bowman's space, and how is it separated from the urinary space?

Answer 27

1. Fenestrated 2. Visceral 3. Mesangial; by capillary or podocyte

Question 28

Kidney, Vascular injection What is in the green box?

Answer 28

Interlobular artery --\> 2 afferent arterioles --\> 2 glomeruli (slightly out of the plane of focus)

Question 29

Kidney, vascular injection 1. What is the green arrow pointing to? 2. What about the green circle?

Answer 29

1. Arcuate artery 2. Vasa rectae

Question 30

Green arrow?

Answer 30

Renal glomerular arteriole, either afferent or efferent

Question 31

Black arrow?

Answer 31

Nucleus of visceral Bowman's epithelial cell (parent of podocytes)

Question 32

Yellow arrow?

Answer 32

Mesangial cell nucleus

Question 33

Blue arrow?

Answer 33

Parietal layer of Bowman's capsule (squamous epithelium)

Question 34

Red arrow?

Answer 34

Endothelial cell nucleus in glomerular capillary loop

Question 35

What is the structure in the green box called?

Answer 35

Juxtaglomerular apparatus

Question 36

What are the white, red, and blue arrows pointing to?

Answer 36

* White: Lacis cells (extraglomerular lacis cells); unknown function * Red: Macula densa; senses Na+ delivery to the distal tubule (component of JG-renin apparatus) * Blue: Juxtaglomerular cells; sense pulse pressure in afferent arteriole, secrete renin in response to drop in pulse pressure in afferent arteriole or decreased Na+ delivery to the distal tubule

Question 37

We're in the medulla now. 1. Yellow circle? 2. Red arrow?

Answer 37

1. Yellow circle: Thin limbs of loop of henle 2. Red arrow: collecting duct

Question 38

Red, black, and white arrows?

Answer 38

1. Red: lumen of renal pelvis 2. Black: renal calyx 3. White: tip of renal pyramid (papilla)