Renal Histology Flashcards
At what point does filtrate become urine?
- when it reaches the storage level
- minor calyxes
What is contained within the cortex of the kidney?
- stellate vessels
- renal columnds
- glomeruli
- corpuscles
- some tubules
- small amounts of type I collagen
What is contained within the medulla of the kidney?
- Loops of henle
- Vasa recta
- collecting ducts
- Hyaluronate and Type I collagen
What are the structures of the nephron in order of flitrate flow?
- bowman’s space
- long proximal convoluted tubule
- short proximal straight tubule
- thin descending limb
- thin ascending limb
- thick ascending limb
- Distal convoluted tubule
- connecting tubule
- collecting tubules
- collecting duct
What are the two types of nephrons?
- juxtamedullary
- superficial
What arteries sprout off of the arcuate artery?
-interlobular arteries
What type of endothelium do capillaries that are contained within the glomerulus have?
-continuous fenestrated endothelium
What is the internal layer of the basal lamina of the glomerulus?
-lamina densa
What is contained within the lamina densa?
- fibronectin
- some type Iv collagen
What is the external layer of the basal lamina of the glomerulus?
-internal and external lamina rara
What is contained within the elamina rara?
- heparin sulfate
- laminin
What type of epithelium is the parietal portion of the bowman’s capsule?
-squamous epithelium
What type of epithelium is the visceral bowman’s capsule made of?
-podocytes
What are podocytes?
Specialized endothelial cells that form the interdigitations through which blood is filtered.
What is the Macula densa?
- the area where the distal tubule comes into contacts with the mother glomerulus
- sensitive to the concentration of sodium and chloride
(T/F) the basment membrane formed by the endothelial cells and podocytes is largely negative.
T
What type of intermediate filament is found in podocytes?
cytokeratin
What is podocalyxin?
- secreted by podocytes
- negatively charged substance that contributes to electric barrier of basement membrane
What protein are filtration slits of the podocyte made of?
-nephrin proteins
What do filtration slits do?
-they block many small proteins from being filtered
At what point is the fluid filtered in the glomerulus considered filtrate?
once it passes through the filtration slits
What proportion of the glomerular endothelial cell is covered by podocytes?
2/3
What proportion of the glomerular endothelial cell is covered by mesangial cells?
1/3
What do mesangial cells do?
- phagocytose debris
- contract
- sample blood glucose
- proliferate in disease
What type of intermediate filament is found within mesangial cells?
vimentin
AND
Desmin
What is a glomerulopathy?
- occurs when the filtration barrier in the glomerulus becomes leaky
- can get protein and blood in the urine
What does angiotensin II do to mesangial cells?
increase contractility
What does ANF do to mesangial cells?
decrease contractility
Where in the tubular system are there the most microvilli?
PCT lumen
What type of intermediate filament do epithelial cells in the loop of henle have?
cytokeratin
What type of epithelium does the loop of henle have?
squamous
What type of epithelium does the distal convoluted tubule have?
simple cuboidal
What type of epithelium does the PCT have?
Low columnar with a glycocalyx
What type of epithelium do the collecting tublules and ducts have?
tall columnar
What causes diabetes incipidus, and what is the primary symptom?
- no ADH
- Lots of peeing
What makes up the walls of the ureters?
- urothelium
- elastic lamina propria
- inner longitudinal smooth muscle
What makes the urothelium special?
- it is make of umbrella/baloon cells, allowing it to expand
- it is transitional
Where is urothelium found>
- calyces
- infundibulum
- renal pelvis
- ureters
- Bladder
- Prostatic urethra
What is the smooth muscle of the bladder?
-detrusor muscle
What are the three portions of the male urethra?
- prostatic
- memranous
- spongy
What type of epithelium does the prostatic portion of the male urethra have?
-ureothium
What type of epithelium does the membranous portion of the male urethra have?
-pseudo columnar
What type of epithelium does the spongy portion of the male urethra have?
-pseudo columnar
What kind of epithelium does the female urethra have?
-stratified squamous non-keratinized epithelium
What does the macula densa do?
- senses NaCl levels
- releases adenosine to control smooth muscle cell tone of the afferent arteriole
What do juxtaglomerular cells secrete?
renin
What are Lacis cells?
- cells in the juxtaglomerular apparatus that transfer information about NaCl tubular load to granular cells
- basically act as extraglomerular mesangial cells
What releases erythropoietin and thrombopoietin?
- medullary interstitial cells in kidney
- liver
What converts Vitamin D into 1,25-Dihydrovitamin D?
-PCT of kideny
What is cystitis and what can it lead to?
- inflammation of the bladder urotheium
- can lead to an unstable urothelium and then cancer
