Renal H&A Flashcards
What is the dense irregular CT on surfact with inner layer of myofibroblasts
Capsule of kidney
What is the renal cortex anatomically
Outer portion containing renal corpuscles
Where do the arteries of the kidney come in
At the renal hilum
What is the renal medulla
Collection of renal pyramids and columns
What are the renal pyramids
Cone-shaped masses in the medulla projecting into calyx
What are renal columns
Tissue lying between pyramids running from cortex to the calyx
What are the renal lobes
Single pyramids plus surrounding adjacent cortex
What is the renal pelvis
Collecting funnel for urine
What are renal calyxes
Out-pocketings of the renal pelvis
What are renal papillae
Projections of medullary pyramids apices into calyxes
What is the order of blood supply (A) to nephrons
Aorta —> renal A —> segmental A —> interlobar A —> arcuate A —> cortical radiate A —> afferent arteriole
Where is the lesser splanchnic N
T10-11
Where is the least splanchnic n
T12
Where are the lumbar splanchnic n
L1-2
What is the parasympathetic innervation of the kidney
Vagus
What does the nephron consist of
Renal corpuscle and renal tubules
Where is the final concentration of urine
Cortical and medullary collecting ducts
What are only found in the cortex
PCT and DCT
What do cortical rays contain
Renal corpuscles, convoluted and straight tubules of the nephron, and portions of collecting ducts
What is contained in the medulla
Renal columns and renal pyramids
What are the medullary rays
Aggregation of collecting ducts and straight tubules running between renal corpuscles and convoluted tubules
What is in the renal interstitium
Fibroblasts that produce EPO based on O2 levels
What are glomerulus
Tufts of capillaries that are fenestrated
What are the layers of bowman’s capsules
Visceral layer - consisting of podocytes
Parietal layer - simple squamous epithelium
Glomerular space between the two layers
Where do we get our first primitive urine
Glomerular capsular space
What is the origin of PCT
Urinary pole
Where do the afferent and efferent arterioles meet
Vascular pole
What are the characteristics of the glomerular endothelium
- thick luminal glycocalyx
- large number of aquaporins
- can generate NO and PGE2
What layer are the podocytes in
Visceral layer
What do the podocytes do
They function in filtration through their ECM
This can be regulated by the cells to make filtration easier or harder based on the conditions
What are the three filters that function in between the glomerular capsule and the PCT
- The fenestrations in the capillaries
- The basement membrane
- The filtration slits that the podocytes give off
Where are the basement membranes
Fused basement membranes of the endothelium and podocytes
What is the size that goes through the filtration membranes
70 kDa
What passes through the filtration membrane
Water, ions, glucose, amino acids, and urea
What is the volume through the kidneys
About 45 gallons/day
What is the general charge of the glomerular basement membrane
Negative
What is the composition of the glomerular basement membrane
Type IV and XVIII collagens, laminin, entactin, proteoglycans
Damage to the basement membrane manifest as
Albuminia - urine albumin levels that are higher than normal
What are mesangial cells
They are support cells that are in between the capillaries
What are the roles of the mesangial cells
- support glomerular loops and ECM of podocytes
- phagocytose cellular debris and protein aggregates
- control glomerular filtration rate
- prevents glomerular distension due to high glomerular BP
- secrete GF and cytokines in response to injury
- proliferate in certain kidney diseases
What is the most abundant tubule
PCT
What is the most active tubule in resorption and secretion
PCT
What are the characteristics of the PCT
- simple cuboidal to columnar epithelium
- tall microvilli
- abundant mitochondria
What are the basal and lateral cell membranes high in
NaK ATPase
Aquaporins
sGLT2
The proximal straight tubule is different than the PCT in what way
- shorter microvilli
- high affinity sGLT1
What portion of the kidney is targeted with glucose removal drugs
PCT
What is the thin portion of the loop of henle made of
Simple squamous lacking brush border
What is the thick ascending segment
Simple cuboidal with numerous microvilli
What does the loop of henle do (generally)
Set up hyperosmotic gradient
What is associated with the thick ascending segment
Capillaries to move reabsorbed ions back into circ
What type of cells are in the DCT
Simple cuboidal epithelium with sparse microvilli and smoother than PCT
What other portion of the kidney is the DCT associated with
Macula densa
Where does angiotensin II influence kidneys
DCT
Where is the final urine osmolarity determined
Collecting tubule/ducts
What are the 2 types of cells in the collecting tubules
Light cells (principal cells) - targets of aldosterone
Dark cells (intercalated cells) - involved in H+ and bicarb xport
Where does EtOH affect kidneys
Collecting tubules
Where does ADH and aldosterone affect kidneys
Collecting tubules
What side of the glomerulus higher pressure
Afferent
Where do peritubular capillaries arise from
Efferent arterioles
What do peritubular capillaries surround
Convoluted tubules
What do peritubular capillaries reup
H2O and salts
What do the vasa recta arise from? What do they run along?
Efferent arterioles; loop of henle
What cells secrete renin with low BP
Juxtaglomerular cells
What does the macula densa function in
Monitors salt levels and signals release of renin if sodium is low
What all does renin control
Sodium retention, blood volume, and blood pressure
When is the transitional epithelium relaxed
Empty bladder
What are the layers of the transitional epithelium
Superficial, intermediate, and basal
Where are the fusiform vessibles and urothelial plaques
Superficial layer of transitional epithelium
What proteins keep urine from coming back into circulation
Uroplakin
What is the function of fusiform vesicles
They add more plasma membrane when the cell is distended and take it back up when relaxed
What prevents backflow of urine
Oblique exit of ureters from renal pelvis
What is the long fibromuscular tube carrying urine from the kidneys to the bladder
Urerters
What are the layers of the muscularis? They are in the ___________?
Inner logitudinal layer
Outer circular layer
Outer longitudinal layer
Ureter
What does the muscularis anchor to
Adventitia
What is the trigone
Where the 2 ureters and urethra open
What are the muscle walls of the bladder called
Detrusor muscles
What type of cell is the majority of the urethra
Pseudostratified columnar epithelium
What type of cells are found at the distal end of the urethra
Stratified squamous epithelium
Why are females more prone to UTI
Shorter length of urethra
Which part of the bladder is voluntrary? Involuntary?
External urethral sphincter - voluntary skeletal muscle
Internal urethral sphincter - involuntary SM
What are the three named regions of the male urethra
Prostatic urethra - passes through prostate gland
Membranous urethra - through urogenital diaphragm; homologous to that found in females
Spongy (penile) urethra - passes through the penis and surrounded by cylindrical erectile tissue
What type of cells are found in the most distal end of the urethra in males
Stratified columnar
What are the 2 functions of the male uretra
Transport urine and semen
