Exam 4: Urinary System Flashcards
List functions of the kidney
fluid/electrolyte balance
acid-base balance
BP regulation
endocrine
activate vitamin D
What two endocrine substances does the kidney secrete?
Renin
Erythropoietin
Renal Lobe
fused subunits of kidney (all domestic mammals)
Renal Papilla
apex of renal pyramid
Renal column
sides between pyramids
What is different about the pig kidney?
papillae show fused cortical parts of renal lobes
Renal Crest
formed by fused papillae
in dog, cat, horse, small ruminant
Area cribosa
part of renal crest where urine is discharged
Papillary ducts
empty urine
have papillary foramina (little opens in ducts)
Unilobar vs. Multilobar Kidneys
unilobar- papillae form renal crest
multilobar- many papillae, NO crest
What animals have a unilobar kidney?
cat, dog, horse, small ruminant
What animals have a multilobar kidney?
pig, large ruminant, humans
What are 2 parts of microanatomy of kidney?
Fibrous capsule
Parenchyma
What tissue makes up outer layer of fibrous capsule of kidney?
DICCT
What tissue makes up inner layer of fibrous capsule of kidney?
smooth muscle (except cat)
What is the parenchyma of kidney?
“functional” tissue of the organ
What two things make up the uriniferous tubules of the parenchyma of the kidney?
nephron + collecting duct
Where are renal corpuscles located in the kidney?
cortex only
What 3 structures are seen in the cortex of the kidney?
renal corpuscles
medullary rays
cortical labyrinth
What are medullary rays?
longitudinal bundles of tubules
“radiating” from medulla into cortex
What is the cortical labyrinth?
area between medullary rays
What structures are within the cortical labyrinth? (3)
proximal + distal convoluted tubules
renal corpuscles
What are the 6 segments of the nephron?
- Glomerular capsule
- Proximal convoluted tubule
- Proximal straight tubule
- Thin tubule
- Distal straight tubule
- Distal convoluted tubule
What are the 2 layers of the glomerular capsule?
parietal layer
visceral layer
What tissue type is the parietal layer of the glomerular capsule made of?
simple squamous epithelium
What unique structure is present in the visceral layer of the glomerular capsule?
podocytes
What are the 3 parts of the podocytes?
primary process
secondary process (pedicel)
filtration slits
What two things make up the renal corpuscle?
glomerulus + capsule
Vascular pole
part of renal corpuscle where afferent arteriole enters and efferent leaves
Tubular (urinary) pole
part of renal corpuscle that continues as proximal convoluted tubule
Urinary space
space between parietal and visceral layers of the glomerulus
What 3 things make the filtration barrier?
Porous endothelium
Basement membrane
Filtration slit membrane
Mesangial cell function + location
influence glomerular filtration
between glomerular capillaries
Which nephron segment is the longest?
proximal convoluted tubule
Which nephron segment is seen most often?
proximal convoluted tubule
Where is the proximal convoluted tubule located?
cortical labyrinth in cortex
How does proximal convoluted tubule stain/appear on microscopy?
bright pink cytoplasm
“fuzzy” border
Proximal straight tubule is equivalent to (descending/thick | ascending/thick) limb of Loop of Henle
descending / thick
Distal straight tubule is equivalent to (descending/thick | ascending/thick) limb of Loop of Henle
ascending / thick
How does the distal convoluted tubule appear on microscopy?
smaller cells, see more nuclei
NO brush border = smooth luminal surface
What segments of the nephron make up the Loop of Henle?
proximal straight tubule
thin tubule
distal straight tubule
What is the Loop of Henle’s function?
hypertonicity
increase Na+/water concentration
= urine concentration
What is the macula densa? What segment of the nephron is it part of?
part of distal straight tubule next to renal corpuscle
What is the function of the Macula Densa?
Na/Cl ion chemoreceptor cells to relay into to JG cells
Where is the distal convoluted tubule located?
cortical labyrinth only
What is the function of the distal convoluted tubule?
sodium reabsorption
potassium secretion
What is the distal convoluted tubule dependent on?
aldosterone
What disease occur with lack of aldosterone?
Addison’s Disease
What is the function of the collecting tubule?
move urine into renal pelvis via papillary ducts
recover good materials so bad can be excreted
What tissue type is the collecting tubule made of?
simple cuboidal epithelium
List order of arterial supply of kidney
aorta –> renal A –> interlobar A –> arcuate A –> interlobular A –> afferent arteriole –> glomerulus –> efferent arteriole –> 3 different pathways
What are the 3 pathways that the efferent arteriole supplies blood to the kidney?
- peritubular plexus
- arteriolae rectae spuriae
- arteriolae rectae verae
What does the peritubular plexus supply blood to?
outer cortical nephrons
What does the arteriolae rectae spuriae supply blood to?
juxtamedullary nephrons (deep in medulla)
What does the arteriolae rectae verae supply blood to?
medulla
What are end arteries in the renal lobule?
arterial branches w/o collateral blood supply
What are the 3 parts of the Juxtamedullary Apparatus?
Macula Densa
Juxtaglomerular cells
Mesangial cells
What are Juxtaglomerular cells?
modified smooth muscle cells in tunica media of afferent arteriole
What are the functions of JG cells?
release Renin (when pressure low)
Convert Angiotensinogen –> Angiotensin I
What is the Renal Stroma?
loose connective tissue between all tubules
What is the function of the Renal Stroma?
produce fibers / prostaglandins to influence flow
What are two differences about the cat kidney?
capsular veins
lipid droplets
Function of Capsular Veins
collect blood from outer part of cortex and drain into hilus
Where are lipid droplets located in cat kidneys?
proximal convoluted / straight tubules
What is different about the Macula Densa of the horse?
composed of stratified squamous epithelium (instead of simple)
unknown functional difference
What substance influences water reabsorption in the collecting tubule?
ADH (anti-diuretic hormone / vasopressin)
What disease results from no ADH production?
Diabetes Insipidus
Renal Pelvis
expanded end ofo ureter
Which species doesn’t have a renal pelvis?
bovine kidney
(T/F) The Renal Pelvis and the Ureter are the same microscopically.
True
What is the only difference in the ureter and urinary bladder microscopically?
thickness (bladder has thicker smooth muscle layers than ureter)
What tissue type lines the Tunica mucosa-submucosa of the ureter/bladder?
transitional epithelium = “urothelium”
Within the Tunica mucosa-submucosa, what 2 possible tissue types can the lamina propria-submucosa made of?
Loose CT or
DICCT
(T/F) Glands are present in the Tunica mucosa-submucosa of the ureter/bladder.
False - except horses
What muscle makes up the Tunica muscularis of the ureter/bladder?
Detrusor M
How many smooth muscle layers are in the Tunica muscularis of the ureter/bladder?
3
The smooth muscle layers of the Tunica muscularis are oriented as follows: (longitudinal/circular), (longitudinal/circular), (longitudinal/circular).
inner longitudinal
middle circular
outer longitudinal
What are the two ways the bladder differs from the ureter?
star-shaped lumen for distention
thicker muscle layers
What is the difference between the visceral peritoneum of the dog vs. cat?
cat- fully covers bladder/ureter
dog- covers most, not all bladder/ureter
What is the outer-most layer of the ureter/bladder called that is easily damaged with microscopy prep?
Tunica Adventitia/Serosa
What is different about the Propria submucosa of the ureter of the horse?
mucous glands present = cloudy urine
The horse has mucous glands present in the (cranial/caudal) half of the ureter.
Cranial half
What are the 3 Tunics of the Female Urethra?
Tunica mucosa-submucosa
Tunica muscularis
Tunica adventitia
What tissue type is the tunica mucosa-submucosa of the female urethra?
transitional epithelium
(T/F) The Tunica mucosa-submucosa of the ureter/bladder/urethra have a lamina muscularis.
False
What lamina propria of the tunica mucosa-submucosa of the female urethra is made of what tissue type? What unique structures are within?
Loose CT
large vascular sinuses
(T/F) The Tunica adventitia is present in the female urethra, but no Tunica serosa is present.
True