Renal anatomy and physiology

Question 1

What are the rough dimensions of each kidney?

Answer 1

11cm long, 5cm wide and 3cm thick

Question 2

The kidneys lie on the anterior surface of which muscle?

Answer 2

psoas major

Question 3

Which kidney lies 1.5cm superior to the other?

Answer 3

Left

Question 4

The upper pole of each kidney is roughly associated with which rib?

Answer 4

11th rib

Question 5

The lower border of both kidneys approximates to which vertebral level?

Answer 5

L3.

Question 6

Describe the approximate vertebral level of the hila of each individual kidney

Answer 6

Left hilum = L1 vertebral level
Right kidney = L1-2.

Question 7

Which kidney has the following relations?

Posterior: Quadratus lumborum, diaphragm, psoas major, transversus abdominis

Anterior: Hepatic flexure of colon

Superior: Liver, adrenal gland

Answer 7

Right

Question 8

Which kidney has the following relations?

Posterior: Quadratus lumborum, diaphragm, psoas major, transversus abdominis

Anterior: Stomach, Pancreatic tail

Superior: Spleen, adrenal gland

Answer 8

Left

Question 9

With what structures does the right kidney have direct contact without a layer of peritoneum in between?

Answer 9

Right suprarenal gland
Duodenum
Colon

Question 10

With what structures does the right kidney have contact WITH a layer of peritoneum in between?

Answer 10

Liver
Distal part of small intestine

Question 11

With what structures does the left kidney have direct contact without a layer of peritoneum in between?

Answer 11

Left suprarenal gland
Pancreas
Colon

Question 12

With what structures does the left kidney have contact WITH a layer of peritoneum in between?

Answer 12

Stomach
Spleen
Distal part of small intestine

Question 13

Each kidney and suprarenal gland is enclosed within a common layer of investing fascia, derived from the transversalis fascia. It is divided into anterior and posterior layers.

What is the name given to this fascia?

Answer 13

(Gerotas fascia).

Question 14

Describe the general structure of the kidney

Answer 14

outer cortex and an inner medulla which usually contains between 6 and 10 pyramidal structures.
The papilla marks the innermost apex of these.

Question 15

What is found in the renal sinus

Answer 15

1. Branches of the renal artery
2. Tributaries of the renal vein
3. Major and minor calyces’s
4. Fat

Question 16

At the renal hilum which structures lies most anteriorly and which most posteriorly?

Answer 16

The renal vein lies most anteriorly,
then renal artery (it is an end artery)
ureter lies most posterior.

Question 17

What percentage of resting cardiac output is received by the kidneys

Answer 17

up to 25%

Question 18

how does the kidney autoregulate its blood flow at a variety of different blood pressures?

Answer 18

myogenic control of arteriolar tone, both sympathetic input and hormonal signals (e.g. renin) are responsible

Question 19

Does the renal cortex or medulla have more blood flow?

Answer 19

renal cortical blood flow > medullary blood flow
(i.e. tubular cells more prone to ischaemia)

Question 20

Total volume of plasma per unit time leaving the capillaries and entering the Bowman’s capsule =?

Answer 20

Glomerular filtration rate (GFR)

Question 21

Volume plasma from which a substance is removed per minute by the kidneys =?

Answer 21

Renal clearance

Question 22

Properties of substances used to measure GFR

Answer 22

1. Inert
2. Free filtration from the plasma at the glomerulus (not protein bound)
3. Not absorbed or secreted at the tubules
4. Plasma concentration constant during urine collection
   examples: inulin, creatinine

Question 23

Main function of tubules

Answer 23

reabsorption and secretion

Question 24

in which part of the tubule is up to 2/3 of water reabsorbed?

Answer 24

Proximal tubule

Question 25

the thin ascending limb of the Loop of Henle is impermeable to water. TRUE/FALSE?

Answer 25

TRUE
but highly permeable to sodium and chloride ions