Renal Anatomy and Histo Flashcards
(49 cards)
1
Q
What are the points of constriction on the ureter?
A
- uretopelvic junction
- Over common/external iliac
- Uretovesical junction
2
Q
List the vessels from renal artery to renal vein.
A
- Renal artery
- Segmental
- Interlobar arteries
- Arcuate arteries
- Interlobular arteries
- Afferent arterioles
- Glomerular capillareis
- Efferent arterioles
- Peritubular capillaries
- Interlobular veins
- Arcuate veins
- Interlobar veins
- Renal vein
3
Q
What makes up the sympathetic renal plexus?
A
- Lesser splanchnic
- Least splanchnic
- Lumbar splanchinic
4
Q
Where does the renal plexus synapse?
A
Aorticorenal ganglion
5
Q
What is a defining feature of the renal cortex?
A
Renal corpuscles
6
Q
What are cortical labyrinth?
A
- Between medullary rays contains the RC + convoluted tubules + collecting tubules
7
Q
What makes up the medulla?
A
- consists of renal columns and cone shaped masses called renal pyramids
8
Q
What is a uriniferous tubule?
A
- Nephron + Collecting tubule
9
Q
Where is erythropoietin produced from?
A
Fibroblasts in the renal interstitium
10
Q
Whats responsible for final concentration of urines?
A
Cortical and medullary collecting ducts
11
Q
What makes up the renal corpuscle and what are the components made of?
A
- Glomerular capillary tuft, which are fenestrated with open pores
- Bowman’s Capsule composed of:
- Parietal layer-simple squamous
- Visceral layer- podocytes
- Glomerular space- primary filtrate
12
Q
What is the red line and blue line?
A
- Red is the vascular pole where afferent arteriole comes in
- Blue is the urinary pole where urine enters proximal convoluted tubule
13
Q
What is secreted by glomerular endothelium?
A
- AQP-1 water channels
- NO and PGE2
- Contains plasma membrane bound glycocalyx
arrows are glomeruluar endothelium
14
Q
Where are podocytes found and what do they do?
A
- Found on the visceral layer of bowmans capsule
- They wrap around glomerular endotheliuim and give off primary and secondary foot processes
- secondary create filtration slits
- size selective and charge selective
- Nephrin is part of the diaphragm that covers podocytes and repels positively charged proteins
- secondary create filtration slits
15
Q
Describe the glomerular basement membrane and its function?
A
- Physical and ion selective filter made up of multiple collagens, laminin, fibronectin, and heparin sulfate
- Restricts large protiens such as albumin and hemoglobin
- albuminuria or hematuria indicates damage to GBM
- Negative charge restricts movement of anions
16
Q
If protein leaks through the GBM, what usually happens to it?
A
Gets reabsorbed by proximal convoluted tubule
17
Q
What makes up the filtration apparatus of the kidney?
A
- Glomerular endothelium
- GBM
- Visceral layer of bowmans capsule
All are contained within the renal corpuscle
18
Q
What is bowmans space, what does it contain, and what is it continuous with?
A
- Space btw visceral and parietal layers of bowmans capsule
- contains the glomerular ultrafiltrate aka primary urine
- Continuous with proximal convoluted tubule at the urinary pole of the renal corpuscle
19
Q
What are mesangial cells?
A
- Function in phagocytosis and endocytosis, structural support, secrete IL-1, PGE2, PDGF and modulate glomerular distension via contraction
- Located in the renal corpuscle most obvious near the vascular stalk
20
Q
Where is the only place that proximal convoluted tubules can be found?
A
Renal cortex
21
Q
What does the PCT do?
A
- Recieves ultrafiltrate from bowmans space and reabsorbs about 65% of it
- Made of simple cuboidal to columnar with apical brush border (gives foggy appearance inside the PCT)
*
22
Q
What does the PCT reabsorb and how?
A
- Na/K/ATPase actively reabsorb Na
- Cl passively diffuses
- H2O follows via AQP-1
- AA sugars and polypeptides reabsorbed via SGLT2
- Proteins and large peptides are endocytosed
23
Q
What is the proximal straight tubule? (P)
A
- aka thick descending limb of the loop of henle
- shorter than PCT
- Less brush border
- Contains SGLT1 high affinity sodium glucose co transporter
24
Q
What makes up the thin descending limb and its functions?
A
- highly permeable to water less permeable to NaCl and urea
- Water diffuses out
- Simple squamous without brush broder
- (tL on picture)
25
Distal straight tubule (thick ascending limb of LOH)?
* Simple cuboidal with microvili but no visible bruch border
* Cortical and medullary
* Na K and Cl diffuse out of filtrate into the interstitium
* NO water movement
* Nucleus is in the apical section and cells buldge into the lumen
* D and TAL
26
Distal convoluted tubule?
* Simple cuboidal epi no brush border, smoother and larger lumen
* Shorter than PCT cells
* Reabsorbs Na and bicarb
* Secretes K and NH4
* **DCT exchanges Na for K under aldosterone regulation**
27
What are the collecting tubules/ducts?
* simple squamous to cuboidal epithelium
* As you move to medulla they become simple cuboidal to columnar
* See cell broders in histo
28
what is this
Collecting duct, there are identifiable cell borders
29
What are the two cell types found in collecting ducts/tubules?
* Light cells (Principal cells): with a single cilium
* target of **adh** regulated AQP2 channels
* Dark cells (intercalated cells):
* alpha intercalated secretes H
* Beta intercalated secretes bicarb
30
What is the primary function of the collecting duct?
* water reabsorption via aldosterone regualtion
31
What are vasa recta?
* vasculature that surrounds the LOH from efferent arterioles
* Participate in countercurrent exchange and concentration of urine
* Descending is continuous endothelium but ascending has fenestrations
32
What are peritubule capillaries?
* From efferent arterioles surround CT
* Fenestrated endothelium
* Re uptake of water and salt
* Gives off vasa recta
33
What is the Juxtaglomerular apparatus?
* located near vascular pole of renal corpuscle and terminal portion of straight tubule
* Regulates BP via activation of RAAS at times of low sodium/BV
* Macula densa cells "sensa" low sodium
* Triggers release of renin from JG cells
34
Left vs right?
* empty bladder made of transitional epi
* Full bladder made of transitional epi
35
Where can transitional epitheium be found? What is it impermeable to?
* lines calyces, ureters, bladder, and intial segment of the urethra
* Impermeable to salts and waters
36
what are the three layers to the transitional epithelium?
1. Superifical- stretches/relaxes
2. Intermediate- slides
3. Basal- stem cells
37
What allows for the unique properties of transitional epithelium?
* Modified areas of plasma membrane called **Plauqes** made of **uroplakin proteins**
* give areas more thickness and prevents diffusion of urine into cells
*
38
What is the significance of fusiform vesicles?
* uroplakin proteins housed in fusiform vesicles
* As the bladder fills and distends the vesicles are brought to the surface and release uroplakin proteins to insert more plasma membrane
* As bladder empties uroplakin are endocytosed back to vesicles
39
Describe the layers of ureters
* luminal transitional epithelium
* Sm mm layers:
* inner longitudinal
* middle circular
* outer longitudinal
* Embedded in adipose tissue where vessels and nerves form adventitia
40
What prevents urine reflux?
1. Bladder distends and compresses ureters
2. Contractrion of sm mm of bladder wall compresses ureters
3. Ureters enter bladder obliquely
41
what is this
ureter
42
what is this
bladder
43
what epithelium makes up the origin of the urethra?
Transitional
44
What makes up majority of epitheliuim in urethra?
Psuedostratified columnar
45
What makes up distal end epithelium of urethra?
stratified squamous epi
46
Female urethera?
* Terminates posterior to clitoris
* Membranous part of urethrea penetrates urogenital diaphragm forming external urethral sphincter
47
Describe prostatic urethra?
* Transitional epithelium
* 2-4 cm from neck of bladder through prostate
* ejaculatory ducts enter posteriorly
48
Membranous urethra?
* Urothelium ends here and is made of psuedostratified columnar now
* passes through **deep perineal pouch forms external urethral sphincter**
* Extends 1cm from prostate to bulb of penis
49
Penile (spongy) urethra?
* 15 cm through length of penis opens at glans penis
* surrounded by corpus spongiosum lined with PSCT and transitions to stratified squamous epi at the end
* **Cowpers and urethral glands empty here**
