Lecture 1 - Anatomy of the Renal + Urinary System

Question 1

What are the 4 main functions of the kidney and urinary tract?

Answer 1

1) Excretion - of waste products & drugs
2) Regulation - of body fluid, homeostasis & acid-base balance
3) Endocrine - synthesis of renin, erythropoietin and prostaglandins
4) Metabolism - Vit D metabolised to active form & catabolism of low-molecular-weight proteins, e.g.: insulin, PTH & calcitonin

Question 2

Describe the anatomical locations of the kidneys

Describe the normal size of the kidneys

Answer 2

• Retroperitoneal on the posterior abdominal wall, located between T12 and L3. Left kidney slightly higher up as liver sits on top of right (right more caudal). Hilum at L1 level.
• 11cm long, 6cm wide. 140g.

Question 3

What is the kidney surrounded by? (from out to in)

Answer 3

• Pararenal fat, renal fascia, perirenal fat + the renal capsule

Question 4

Describe how blood enters and how blood leaves the kidneys

Answer 4

• Blood enters via left and right renal artery which branches off abdominal aorta. As renal artery enters hilar region, it branches into anterior and posterior divisons
• Blood leaves via left and right renal vein which feeds into inferior vena cava.

Question 5

On a blank kidney, identify the medulla, cortex, renal pyramids, minor & major calyces, renal pelvis + ureter

Answer 5

EZ

Question 6

What are the 2 major kinds of nephrons found in the kidney and what are the differences between the two?

Answer 6

1) Cortical (85%) - short LOH

2) Juxtaglomerular (15%) - Long LOH

Question 7

On a blank nephron, identify the afferent arteriole, efferent arteriole, glomerulus, bowman’s capsule, PCT, LOH, DCT, collecting ducts.

Answer 7

EZ

Question 8

What cells determine osmolarity which send signals to granular cells to control rate of flow through the glomerulus?

Answer 8

Macula Densa Cells.

Question 9

Describe the complete flow of blood supply (all vessels) from aorta to kidneys and back again

Answer 9

Aorta –> Renal Artery –> Segmental Artery –> Interlobar Artery –> Arcuate Artery –> Interlobular Artery –> Afferent Arteriole –> Glomerulus –> Efferent Arteriole –> Peritubular capillaries/vasa recta –> Same way back but with veins

Question 10

Describe the composition and course of ureters into the bladder

Answer 10

• 25-30cm long with lining of smooth muscle to provide peristalsis. Split into abdominal, pelvic and intramural segment. They are retropeitnoeal, and run lateral to transverse processes of lumbar vertebra.
• They enter the posterolateral surface of the bladder (vesicoureteral junction) at an oblique angle (to prevent reflux)

Question 11

What are the differences in the course of the ureter between men and women

Answer 11

In males:
- Describe that the ureter passes under ductus deferens, superior to seminal vesicles

In women:
- The ureter descends posterior to ovary
and into base of broad ligament, passing under uterine artery

Question 12

What is the anatomical position of the bladder?

Answer 12

Posterior to the pubic symphysis, anterior to vagina + uterus in women, anterior to rectum in men.

Question 13

What is in the wall of the bladder?
What is within this muscle that allow for contraction and expansion?
How much on average can the bladder hold?

Answer 13

• The detrusor muscle
• Rugae (muscular folds)
• 750mL

Question 14

What is the triangular area of the bladder called and what is this area defined by?

Answer 14

• Trigone

- 2 x ureteric opening and tip of the bladder

Question 15

What is the lumen of the ureter coated with?

Answer 15

• Urothelium, a continous epithelial layer, continuous with the bladder, ureter and pelvis of the kidney.

Question 16

What is the anatomical position of the prostate?

Answer 16

Inferior the the bladder, anterior to the rectum

Question 17

On a blank picture of a urethra, identify:

In females:
- IUS, EUS

In males:
- prostate gland, prostatic urethra, membranous urethra, bulbous urethra, penile/spongy urethra and external urethral meatus

Answer 17

EZ