Anatomic Overview of the Kidneys Flashcards
Name the 4 parts of the kidney
- glomeruli 2. tubules 3. interstitium 4. vascular
Name some functions of the nephron (4)
- fine tuning of substances 2. produce filtrate 3. add and subtract large volumes of substances 4. reabsorb (conserve) water
Where are the kidneys?
- retroperitoneal with right kidney more cranial than left kidney - dogs: right kidney attached - cats: kidneys pendulous and moveable
The renal pelvis is an extension of what?
the proximal ureter
What collects in the renal pelvis?
urine
Is there peristalsis in the ureter?
yes!
Which area of the kidney receives the most cardiac output?
renal cortex (4-5 ml/min/kg)
What is the total percentage of cardiac output that the kidneys receive?
20-25%
Renal vessel sequence
renal artery - dorsal and ventral rami - interlobar arteries - arcuate arteries - interlobular arteries - afferent arterioles - glomerular capillaries - efferent arterioles - peritubular capillaries - vasa recta - 2nd capillary bed - venous return
Why do the kidneys receive such a large proportion of the cardiac output? A. Because the kidneys have an unusually high demand for oxygen B. Because it permits the kidneys to produce a large quantity of glomerular filtrate C. So that the kidneys can monitor adequacy of the red blood cell mass D. All of the above
B. Because it permits the kidneys to produce a large quantity of glomerular filtrate
What are the two sphincters of the glomerular capillary bed?
- pre-glomerular capillary sphincter 2. post-glomerular capillary sphincter
How many nephrons make up a kidney in the cat and in the dog?
cat: 200,000 dog: 500,000
- glomerulus
- proximal convoluted tubule
- proximal straight tubule
- thin descendling limb (loop of Henle)
- thin ascending limb (loop of Henle)
- thick ascending limb
- macula densa
- distal convoluted tubule
- connecting tubule (distal straight tubule?)
- cortical collecting duct
- medullary collecting duct
- papillary duct
What is unique to the renal cortex?
glomeruli!
What makes up the renal corpuscle?
Bowman’s capsule
glomerulus
What makes up the glomerular filtration barrier?
endothelium
basement membrane
podocytes
The area between podocyte foot processes is known as what?
slit diaphragm
Which of the following are components of the glomerular filter?
A. The glomerular basement membrane
B. The endothelial cells
C. The epithelial cells
D. All of the above
E. A and B
F. A and C
G. B and C
D. All of the above
Name the 2 principal sites of ultrafiltration
glomerular basement membrane
slit processes of the podocytes
What is reabsorbed in the proximal tubules?
amino acids
glucose
HCO3
phosphate
Na+
Explain absorption and excretion in descending limb of loop of Henle
water reabsorbed
Na+ excreted into tubule
What is reabsorbed in the thick ascending limb of loop of Henle?
Na+
(impermeable to water!)
Explain absorption and excretion in the distal tubules
fine tuning absorption and excretion of the following:
Na+
K+
Ca2+
H+
What is reabsorbed in the collecting duct?
water
What characteristics of the proximal tubules facilitate reabsorption?
- apical intercellular tight junctions
- apical membrane brush border (microvilli)
- basolateral intercellular interdigitations
- prominent mitochondria associated with infoldings of basolateral membranes
Where are the juxtaglomerular cells located?
in the afferent arteriole
Where is the macula densa located?
in between the afferent and efferent arterioles
What are the two types of cells in the collecting duct?
principal cells
intercalated cells
What influences water balance in the collecting duct?
ADH
