Urinary System 2: Ureters, Bladder, & Urethra Flashcards
PCT is the 1st
segment of the renal tubule
Where Does the PCT begin?
at the urinary pole of the glomerulus
Where does a majority of glomerular flitrate get resorbed?
PCT
70%
PCT is very very
convoluted
what are the name in order of the parts of the Loop of Henle?
- Pars recrta (thick)
- thin descending
- thin ascending
- thick ascending limb
The thin portion of the loop of Henle has
squamous epithieum
The thick parts of the Loop of henle has
cubodial epitheilum
What wraps around the loop of henle?
Vasa recta
is parallel to
Loope of henle serves to create
high osmotic pressure in the renal
medulla
The loop of Henle creates high osmotic pressure in the renal medulla via the
counter-current multiplier system
The loop of henle counter-current multiplier system hel to create
hypertonic urine
excretion of excess solute
The bulk of the loop of henle extends into the
medula
In juxtamedullar nephorns thin limbs are
long
in cortical neprhons thin limbs are
short
Pars recta has a
brush border
There is a _________ extracellular Na in the medulla
higher
Countercurrent multiplier funciton is to
to generate high osmotic pressure in ECF of renal medulla
How does the Countercurrent multiplier generate hgih osmotic pressue inthe ECF
via Na-K pump in thick acsending
The vasa recta arises form
efferent arterioles of
juxtamedullary
nephrons
Distal convoluted tubule continuation of
thick ascending
limb of Loop of Henle
Where is the DCT located
in the cortex
DCT has cuboidal epithelium but
lacks brush border
DCT is Responsible for
- active resorption of Na & Cl
- coupled with secretion of H & K ions
What are the two cell types of the DCT?
- prinicpal cells
- intercalated cells
prinicpal cells resorb
Na & water
prinicpal cells secrete
K
intercalated cells mediate secretion of
H + and HCO3 −
intercalated cells mediate reabsorption
Cl − and K+
What is important Regulators of Acid- Base Balance
intercalated cells
intercalated cells are important
Regulators of Acid- Base Balance
prinicpal cells and intercalated cells are controled by
aldosterone
adrenal mineralocorticoid
JGA stands for
juxtaglomerular apparatus
Juxtaglomerular apparatus is combined
- baroreceptor (pressure)
- chemoreceptor ([ion]
Juxtaglomerular apparatus regulates
blood pressure
Juxtaglomerular apparatus regualtes blood pressure via
renin-angiotensin-aldosterone system
(RAAS)
parts of the renin-angiotensin-aldosterone system
(RAAS)
- macula densa
- juxtaglomerular cells
- extraglomerular mesangial cells
Macula densa __________ sensitive to changes in ________in filtrate.
Chemoreceptor; Na
Macula densa are found in
side of distal convoluted tubule
Juxtaglomerular cell are found in
wall of afferent arteriol
Juxtaglomerular cells Act as _________; detect changes in _______
baroreceptors; blood pressure
Juxtaglomerular cells produce ______ in response to low BP
renin
decrease Blood volume
Renin converts
angiotensinogen to angiotensin
Extraglomerular mesangial cells are found
surrounding afferent and efferent arteriole
Extraglomerular mesangial cells fucntion
unclear; provide structural support & phagocytosi
Extraglomerular mesangial cells may assist in
tubular glomerular feedback
info from macula densa to intraglomerular mesangial cell
What watch if the BP is low
- Macula Densa
- Juxtaglomerular
intraglomerular mesangial cells
function
contraction/relaxation may change glomerular filtration rate
Macula densa acts as sensor, regulating
juxtaglomerular
function by monitoring Na+ &
Cl- levels in the DCT
Angiotensinogen is converted to
active
angiotensin 1
by renin
Angiotensin causes
suprarenal glands to secrete
aldosterone
What converts Angiotensin 1 to 2
ACE
Angiotensin Converting Enzyme
ACE inhibitors helop to treat
hypertesnion (high blood pressure)
DCT dumps into
collecting tubules
isotonic urine
Collecting tubules dump into
collecting ducts
isotonic urine
Collecting duct leave
cortex and enters medulla all the way down to the papilla
Collecting Ducts play an important role in
final concentration of urine
interstitium & vasa recta
ADH causes collecting ducts to
increase the number of aquaporins in their walls
Epithelium responsive to
antidiuretic
hormone (ADH, Vasopressin)
antidiuretic
hormone is released by
posterior pituitary
ADH cause
water to be lost from ducts
hypertonic urine
Without ADH
ducts remain
impermeable to water
iso-/hypotonic urine
Mutations to AQP-2
do not respond to ADH
in diabetes
After reaching the papilla what is the order that urine travels?
minor calyces
major calyces
renal pelvis
ureter
Ureter lined by
transitional epithelium
Urinary Bladder lined by
Urothelium (transistental)
ballon surface
Stratified
