HTHSCI 1H06 B Lecture Notes - Lecture 19: Sphincter, Hemodialysis, Ureter
22 Jun 2018
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Department
Course
Professor
RENAL TUBULES
.
→UUBUU
§
Reabsorption of
material from
The Nephron the filtrate in
the tubule to
fthe blood
•
Renal corpuscle :makes filtrate
asome chemicals
•
Renal tubule +Collecting duct : make urine secreted from
blood to the
•
Afferent arteriole blood goes Into the glomemly,and goes out Into the etttuht arteriole tubule
Ipenicillin →
•
Peninsular Capillaries are downstream filtrate →
urine )
•blood goes back into general
circulation
1some made into filtrate through filtration )
hat to do with 180L of filtrate
→to the meters + then bladder
•there Is alot of stuff in filtrate +some of this material is :
-
completely reabsorbed
>
eg ,glucose ,AA ,bicarb
-
regulated +partially reabsorbed
>
cg .HZO ,NA ,kl U
-
excreted as wall
>eg ,urea ,creahnine ,drugs +their metabolites
what Is gained +What is lost in aday
Amount in Filtrate Amount in Urine
HZO 180L 1-2L
glucose 162g 0
pwtllh 2.0g 0.1g
NA 570g 4g
Uric Acid 8.5g 0.8g
(reatinine 1,69 t.bg
•
After the renal corpuscle ,the nephroh is consumed with reabsorption +secretion
Affluent
Renal corpuscle arteriole
Much Depends on the Renal tubules ¥910
merulwt capsule)
convoluted )
✓
•
Renal Cortex Includes : corpuscle ,distal 4 receives filtrate
+proximal MBUHJ
-
Columns
Convoluted
•
Renal medulla includes :loop of henle +↳final prep for
uvln excretion
collecting duct
-
pyramids .
'
.end up with papilla
and papilla leak urine into calyces
to variably permeable
→
meter →bladder → out of body to
water : amount of
urine is related to
Permeability
t Water permeable i. Hzo tlm permeable to
can Have Wahr but it allows
solutes out
ephron vasculature
•
Arcuate artery →Interlobular artery →At Hunt Arteriole →Renal
Corpuscle →etteent arteriole
•Blood going across tubules + comes from pentnbnlar capillaries needs to be
collected through veins
-
blood goes across tubules ,is collected by the veins ,Vasa recta ,then
ultimately into ornate vein
Resorphon of solutes +Water
•
Reabsorption can occur by either active or passive transport
•Water is moved by osmosis
-
osmosis :apassive mechanism by which Wahr follows its concentration gradient through qsemi permeable membrane
-
The movement of solutes from lnbules to interstitial fluid drives osmosis (requires energy )
-
About 90% of water reabsorption is obligatory Idragged by moving solutes )
-
the last 10% 11 facultative (Cantor tdepending on amount required)
>Much obligatory reabsorption occurs in the proximal tubule and DLOH because theyre water permeable
>facultative reabsorption is controlled by ADH which makes collecting duct permeable AWahr i. Water can leave the ducts →
Interstitial fluid →pentnbulat capillaries
Osmosis +the Proximal Convoluted tubule
••
Movement of hatll It by osmosis
-
linked to passive reabsorption of low twash Iurea )
a,Kila ,mg +Urea
-
Na transport is active .:it moves water by osmosis
>other ions become more concentrated as aresult and begin to diffuse
•Most active area for reabsorption Is the proximal lnbule
is is
no E}oh SEHTFYIAE
'¥ansp .or
-
By the end 100% Of organic solutes +60% of Wahr has
be
EE me £
proximal tubule pd¥pp$$
*I*
at a
Passive transport
•
ldet .)the movement Of solutes often doeiht involve additional energy
•
Para cellular route :solutes slip between light junctions
•Trans cellular route :solutes go into and out of the cells by following electrochemical
gradient
Reritnbular Capillary •Diffusion may be facilitated with transport proteins lglu lose →tubular tell →
interstice fluid)
•
leakage channels for low to go down their lmuhtrahun gradient
Passive sodium Reabsorption
•Brush border : apical membrane of cells which Tsurface area
•
Tight junctions make it Waterproof
•
When Na in interstitial fluid <Na in tubule lumen Na is reabsorbed para cellular ly +para tubular capillaries carry It away
