Urinary Flashcards
How does renin control fluid volume?
Renin
Reabsorbs Na+ through aldosterone release from adrenal
Angiotensin II is made and allows vasoconstriction
What are endocrine products the kidney makes?
Renin
Erythropoietin
Vitamin D metaboltes
Renin purpose
Regulates blood volume/pressure
Erythropoietin purpose
Acts on bone marrow to make new erythrocytes
Vitamin D metabolites
Conversion of Vitamin D to dihydroxycholecalciferol which regulates Ca2+ transport
What is the basic functional unit of the kidney
Nephron
What makes up the renal corpuscle
Glomerulus
Bowman’s capsule
What are the arteries for renal vasculature supply
Renal a Interlobar a Arcuate a Interlobular a (radial) Afferent glomerular arterioles
What are the two types of nephrons
Cortical and Juxtamedullary
Renal vasculature drainage route of cortical nephrons
Efferent glomerular arteriole Peritubular capillary network Stellate v Interlobular v Arcuate v Interlobar v Renal v
Juxtamedullary nephron renal vasculature drainage
Efferent glomerular arterioles Vasa recta Arcuate v Interlobar v Renal v
What is in the glomerulus of the renal corpuscle (4)
Tuft of capillaries (fenestrated)
Intraglomerular mesangial cells (support)
Afferent glomerular arteriole supply
Efferent glomerular arteriole drain
What is in Bowman’s capsule of the renal corpuscle (3)
Visceral Layer: Podocytes that are S.S.E to allow filtration
Bowman’s Space
Parietal layer
What are the 3 mechanisms for filtration?
Fenestrated S.S.E
Thick basement membrane
Podocytes
What is the longest, widest, and most well developed segment of the nephron?
PT
Where is the PT confined?
Renal cortex
Where are the tubular portions of PT located?
pars convoluta
Where are the straight portions of PT located?
pars radiata
PT reasborbs what percent of ions and water of the ultrafiltrate?
75
PT reasborbs what percent of glucose, AA, and proteins of ultrafiltrate?
100
What percents of organic solutes, drugs, and toxins are reabsorbed in PT?
All excreted
What classification of cells line the PT
S.C.E
T/F Cells that make PT sit on a well defned basement membrane
T
T/F There is a well developed brush border in PT
T
T/F Nuclei in PT are apical located
F
Basally
T/F Juxtamedullary nephrons have shorter LOH than cortical nephrons
F
Longer
What is the fxn of LOH (2)
Generate high osmotic pressure in EC fluid of medulla (counter-current multiplier system)
Reabsorption of water back into circulation bia vasa recta (counter-current exchange system)
LOH cell classification
S.S.E
What are differences between LOH and capillaries
Large lumen with more nuclei protruding lumen than capillaries
Epithelial cells slightly thicker than endothelial cells of vessels
Nuclei stain less densely than endothelial nuclei
Lumina contain no erythrocytes
Where are the tubular portions of the DT located
pars convoluta
Where are the straight portions of DT located
pars radiata
DT reabsorbs Na+ how?
Active process controlled by aldosterone release from the adrenal
T/F DT has absorption of ions
T
T/F DT is permeable to water and urea but ions can enter and leave
F
DT is impermeable to water
How does DT control acidity of ultrafiltrate?
Active secretion of H+ ions into lumen
What is the classification of DT cells
Low cuboidal cells
T/F DT has a lot of nuclei that are centrally/apically located
T
What is the ration of cross-section of PT and DT
7:1
Macula densa
- where
- monitors
- instructs
- Specialized portion of the DCT
- Monitors filtrate volume and Na+ concentration
- INstruct JG cells to release renin if necessary
Why is the collecting duct system not considered to be a part of the nephron
Due to its different embryological origin
What are the different parts of the collecting duct system
Collecting tubule
Collectong duct
Duct of bellini (papillary duct)
What does the duct of bellini do
Opens into the area cribosa to drain urine into the minor calyx/renal pelvis
T/F Collecting duct system is always impermeable to water
F
If ADH is present will become permeable to H2O
T/F Portion of collecting duct is permeable to urea
T
Cell classification of collecting tubule of CDS
Cuboidal epithelium
T/F CDS cells stain poorly
T
Termed “clear cells”
What types of cells are in collecting tubule of CDS?
Intercalated cells
- High number of mitochondria and microvillous surface
- Help control acid/base balance by transport of H+
What is the cell classification of collecting duct in CDS?
Columnar epithelium
What types of cells are in collecting duct of CDS?
Intercalated but are less nu,erous in collecting ducts
What kind of cells make up ducts of bellini (papillary ducts)
Columnar epithelium
What are the components of JG apparatus
Macula densa of DT
JG cells of the afferent glomerular arteriole
Extraglomerular mesangial cells ->AKA Polkissen or Lacis cells)
Is the mechanism behind the function of macula densa known?
No
Of the JG apparatus, what cells are modified smooth muscle
JG cells
What do JG cells secrete
Proteolytic enzyme=renin
Regulates blood volume
Alodsterone release from adreanl cortex
Where are EG mesangial cells?
Occupies the space bordered by the afferent artiole, MD, efferent arteriole, and vascular pole of renal corpuscle
What is the EG mesangial cell contiguous with?
Intraglomerular mesangial cells
Is the prcise function of EG mesangial cells known?
no
What are parts of urinary system made of transitional epithelium?
Ureters
Urinary bladder
Urethra- near bladder
What is the part of the urethra farther from bladder made of
Stratified squamous non-keratinixing
What are the organizational layers of lower urinary tract
Mucosa
Lamina propria/submucosa
Tunica muscularis
Tunica adventitia/serosa
The kidney develops from (2)
Ureteric bud
Metanephric mesenchyme
How does the uteric bud form in the development of the mature kidney?
From outgrowth of the mesonephric duct near the cloaca
What are all formed from the ureteric bud, endoderm germ layer origin
Ureter Renal pelvis Major and minor calyces Collecting ducts Collecting tubule
What is the rest of the nephron formed from (other than ureter, renal pelvis, etc)
Metanephric mesenchyme
Mesoderm germ layer origin
What are the layers of the ureter?
Tunica mucosa
Tunica muscularis
Tunica adventitia
In ureter: Tunica mucosa is lined by
Transitional epithelium
Lamina propria
–>Fibroelastic LCT
–>In horse, mucus glands=cloudy urine
In ureter: Tunica muscularis layers
Inner longitudinal smooth muscle layer
Outer circular smooth muscle layer
Outer longitudinal smooth muscle layer
In ureter: tunica adventitia layer
Outer CT layer
mesothelum=S.S.E
Urinary bladder layers
Tunica Mucosa
Tunica muscularis
Tunica serosa
In bladder: Tunica mucosa is lined by
Transitional epithelium cells (impermeable to water/urine)
Lamina propria/submucosa
- ->Fibroelastic LCT and DICT
- Separted by muscularis mucosa in fragmented setions
In bladder: Tunica muscularis is made of
Smooth muscle
In bladder: tunica serosa is made of
Outer CT layer of mesothelium
