physio - chapter 5
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CHAPTER 5: Transport of Solutes and Water
Intracellular Fluid
• Fluid inside the cells and occupies intracellular space
• High in K + and low in Na+ and Cl-
Extracellular Fluid
• Fluid outside the cells and occupies extracellular space
• Low in K + and high in Na+ and Cl-
Na-K Pump = utilied !" cell to maintain the optimal ion contents
in and out o# the cell
$wo %a&or Constituents o# the ECF
• Plasma
• Interstitial Fluid
Protein-Free Plasma = 'Plasma Content in me()L* ) ,.
Efect o Protein Charge
• Non-charged /oluteo 0/uch as 1L2C3/E4 Lipid and Protein 5olume is
the onl" correction !ecause plasma proteins
are net negati5e chargedo 6etain cations in plasma
• Cation Conc o# Protein-Free Plasma = Lowered !" 78
• 9nion Conc : = Higher !" 78
All Body Fluids Have Approx Same Osmolality Each !uid
has E"ual #um$ers o % and & Charges
3smolalit"o descri!es the total concentration o# all particles
that are #ree in a solutiono expressed as the num!er o# osmoticall" acti5e
particles per ;ilogram o# water 0<mosmol);g
o# H<3
Electroneutrality
9ll solutions must respect the principle !ul; o#
electroneutralit" $he num!er o# positi5e charges in the
o5erall solution must !e the same as the num!er o#
negati5e charges
9nion 1ap = di>erence !etween anions and cations in
!lood plasma
' Hydrostatic Pressure = Vessel to intracellular fuid
' Oncotic Pressure = H2O accumulates in cells
Solute (ransport Across Cell )em$ranes
In Passive, Noncoupled transport across a permeable membrane,
a solute moves down its electrochemical gradient
• Electrochemical 1radiento the dri5ing #orce that determines the passi5e
transport o# solutes across the mem!raneo di>erence !etween the actual mem!rane
potential and e(uili!rium potential #or an"
speci?c set o# intra and extra coonco includes the contri!ution #rom the
concentration gradient o# the soluteo @eterminants o# Electrical Potential Energ"
Concentration 1radient
Aoltage @i>erence
• Noncoupled $ransporto %o5ement o# a su!stance means the
mo5ement o# it across the mem!rane is not
directl" coupled to the mo5ement o# other
solutes
@i> EC)IC Conc o# /oln with No Aoltage @i> = oncentration
!radient as dri5ing #orce
/ame E)IC Conc o# /oln BI$H Aoltage @i> = "lectrical !radient as
dri5ing #orce
INFL2 D mo5ement o# solute #rom outside to inside
EFFL2 D mo5ement o# solute #rom inside to outside
2nidirectional D mo5ement across the mem!rane in one direction
Net Flux 0Net $ransport 6ate D sum o# two unidirectional uxes
No driving #orce = "$%I&I'(I%) = No net transport
/tead" /tate D conditions related to a su!stance do not change
with time
Bhere
x = 5alence o# solute x = net dri5ing #orce 0&ou)m4xo = conc outside Gi D Go = mem!rane potentixi = conc inside 6 = gas constantF = Farada"s Constant
I# NE$ @6IAIN1 F36CE is not E63 = not in e(uili!riumNerst E(uation = descri!es the conditions when an ion is ine(uili!rium across a mem!raneIn *I)P&" +I%*ION, the fu- o# an uncharched substancethrough membrane lipid is directly proportional to itsconcentration gradient.*ntegral )em$rane Proteins. $"pes o# Protein Pathwa"s
• Poreo 9lwa"s open
o Ex, Porins in the outer mem!ranes o#
mitochondriaJ c"totoxic pore-#orming proteins =
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Per#orin released !" l"mphoc"tes anda(uaporin channels
• Channelo 9lternatel" open and closed !ecause it is
e(uipped with a mo5a!le !arrier or gateo Process is called gating
o 1ated Pore not a 1ated Channel 0Ex, IonChannels4
• Carrierso /urrounds a conduit that ne5er o>ers a
continuous transmem!rane path !ecause it ise(uipped with at least two gates that are ne5eropen at the same time
Porins
• Large-sie pores #ound in outer mem!rane o# gram-
negati5e !acteria and mitochondriao %itochondrial Porin D allows solutes as large as
7;@a to di>use passi5el" #rom c"tosol into themitochondrial mem!rane
Per#orin D pore-#orming protein
released !" c"totoxic $ l"mphoc"tes to;ill their target cells
Eg Complement Cascade D monomer
o# Co Nuclear Pore Complex 0NPC4
6egulates trac into and out o# the
nucleus 5ia acti5e transport Can transport huge molecules
in5ol5ing 9$P h"drol"sis Has 929P36IN #or passi5e transport
*on+,ated Channels
• Consists one or more pol"peptide su!units with a-helical mem!rane spanning segments
• Functional Componentso 1ate D determines whether channel is open or
closedo /ensors D respond to one o# se5eral signals
Change in mem!rane 5oltage
/econd-messenger s"stems D acts at
the c"toplasmic #ace o# the mem!raneprotein
Ligands D!ind to extracellular #ace o#
the mem!rane proteino /electi5it" Filter D determines the classes o#
ions or the particular ions that ha5e access tothe channel pore
o
3pen Channel Pore D pro5ides continuouspathwa" when it assumes open con#ormation!etween two sides o# mem!rane so ions canow through it passi5el" !" di>usion until thechannel closes again
• Channelso Na Channels
Passi5e transport
Aoltage-1ated Na Channels
• 6esponsi!le in generatingaction potential
o K Channels
Fairl" close to ero or somewhat
positi5e
%o5e outward the cell
Has a ma&or role in generating a
resting mem!rane 5oltage that isinside-negati5e
Has a ;e" in excita!ilit" cells where
these channels help terminate actionpotential
o Ca Channels
9lwa"s strongl" negati5e
%o5e into the cell
6apidl" enters the cell down a steep
electrochemical gradient Pla"s a 5ital role in transmem!rane
signaling #or !oth excita!le and non-excita!le cells and generating actionpotential
o Proton Channels
H+ dri5ing #orce generall" tends to
mo5e H into cells i# H5M are open Normall" closed and acti5ates onl"
when the mem!rane depolaries orc"toplasm acidi?es
Help mediate H extrusion #rom cell
during states o# strong mem!ranedepolariation 0during action potential4or se5ere intracellular acidi?cation
o 9nion Channels
%ostl" negati5e electrochemical
dri5ing #orce
Carrier )ediated (ransport Systems
• $rans#ers a !road range o# ions and organic solutesacross the plasma mem!rane
• eha5e according to the general ;inetic scheme
• Can mediate onl" passi5el" or downhill
O Km = 9nit"o /olute Carrier /uper#amil"
@o not either h"drol"e 9$P or couple
to an electron transport chain @i>ers in
• %olecular mechanism
• Kinetic properties
• 6egulation
• /ites o# mem!rane targeting• $issues which the" are
expressed
• @e5elopmental stage at
which the" are expressed 1L2$M = glucose transporter on the
cell sur#ace 1L2$Q = present in the intracellular
sur#aces 2rea $ransporter
3rganic Cation $ransporter
#a-. % Pump & most important primary active transporter/utili0es 1P to e-trude Na and upta3e 4
• 9cti5e $ransport = process that can trans#er a solute
uphill across a mem!rane against electrochemicalgradient
o Primar" 9cti5e $ransport D dri5ing #orce neededto cause net trans#er o# solute againstelectrochemical gradient comes #rom 9$P 0eg,carr"ing hea5ing material to airR P2%P/energied !" 9$Pases4
o /econdar" 9cti5e $ransport D dri5ing #orce is
pro5ided !" coupling uphill and downhillmo5ement o# one or more solute which is a#a5ora!le electrochemical gradient exists 0egseesaw4
Na)K Pump
• 3ccurs !etween a and ! su!unitso S-su!unit
has M transmem!rane segments
catal"tic su!unit
o T-su!unit
one transmem!rane segment
essential #or proper assem!l" and
targeting o# Na-K pump
• Exclusi5e to the !asolateral mem!rane
• 6esponsi!le #or low Na and high K relati5e to the ECF
• %em!er o# large super#amil" o# pumps ;nown as :"56"2
1Pses or P6type 1Pase7
• $wo Con#ormational /tateso EM - !inding sites #or ions #ace inside o# cello E< D !inding sites #ace outside the cell
• /$EP/
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o UM 9$P-!ound EM 9$P state, 9#ter pump has
released two K to the ICFJ Na-!inding sites #acethe ICF and ha5e high anities to Na
o U< Na-!ound EM 9$P .Na /tateo U. 3ccluded EM D P 0.Na+ /tate4 9$P
phosphorelates lea5ing 9@P trigerring minorcon#ormational change in EM #orm the pump nowoccludes . Na ions within the permeationpathwa" 0Na inaccessi!le to ICF)ECF4
o UQ @eocccluded E<-P .Na /tate, EM to E< ha5ing
two e>ects 0M4 Pump !ecomes deoccluded thatNa-!inding site is now open to the ECF 0<4 Na
anities o# these !inding sites decreaseo U7 Empt" E<-P state, . Na dissociate into ECF
and protein undergoes minor con#ormationalchange to empt" E<-P #orm which has highanit" to K
o UV K-ound E<-P <K /tate, < K !ind to pumpo UW 3ccluded E<-K /tate, 6elease o# inorganic
phosphate into ICFo UX @eocludded EM 9$P <K /tate, E< to EM !" 9$P,
E>ects 0M4 pump !ecomes deocludded 0<4Kanities decreased
o 9CK $3 /$EP M
• loc;erso Has high anit" to ECF o# E<-P Cellular K 0/tep
74o Cardiac 1l"cosides
3ua!ain
@igoxin D widel" used #or caridiac
conditions
Other P+type A(Pases
• H-K Pumpo In parietal cells o# gastric glandso Excretes H+ to the apical mem!rane to the
lumen and upta;es K +• Ca<+ Pumps 0Plasma %em!rane Ca 9$Pase-P%C94
o Extrudes Ca #rom cellR Inux o# H in
sarcoplasmic reticulum in muscle cells
• 3ther Pumpso Copper Pump 9$PW D mutated in Bilsons dse
F+(ype and /+(ype A(Pases (ransport H%
F-t"pe or FoFM 9$Paseso 07;@ao Fx
$he hand acts as a tur!ine that
roteates in the plane o# mem!raneJdri5en !" the H ions that ow through
the tur!ine-down the Helectrochemical gradient into themitochondrion
/tic; is an axle 0" and E su!units o#
FM4 that rotates with the tur!ine
Cand" 0a and ! su!units o# FM4 is a
stationar" chemical #actor"J energied!" the rotating axle that s"nthesiesone 9$P molecule #or each M<Y tuno# tur!ine
A-t"pe H+ Pumpo Has l"sosomesJ endosomes and secretor"
5esiclesJ storage 5esicles and the 1olgi9pparatus contain so-called 5acuolar-t"pe 05-t"pe4 H-9$Pase that pumps H #rom c"toplasm tointerior organelles
o Has V su!units
A(P+$inding Casettes 1ABC2 (ransporters 3 can act ashannel, Pumps or (egulators
• 9CM /u!#amil"o Important in mediating eZux o# phospholipids
and cholesterol #rom macrophages and othercells
• %@6 /u!#amil"o %ultidrug 6esistance $ransporterso 9$Pases and primar" acti5e transporters
%@6M)P 1l"coprotein = extrudes
cationic meta!olites and drugs acrosscell mem!rane/ important andclinicall" antagonistic in cancer pxpumping anticancer drugs
• %6P)CF$6 /u!#amil"o Fx as low-conductance Cl- channel as well as
regulator o# other ion channelso Has two mem!rane spanning domains 0%/@M
and %/@<4 with V mem!rane-spanningsegments
o Has < nucleotide-!inding domains 0N@M and
N@<4o Has Protein Kinase 9 and C as regulator"
domainso $wo %echanisms o# 9$P regulating CF$6 Cl
Channel Protein phosphor"lation
Interaction with the nucleotide-!inding
domains
Cotransporters One Class o Secondary Active(ransporters are ,enerally 4riven $y the Energy o the*n5ardly 4irected #a% ,radient /econdar" 9cti5e $ransporters = dri5ing #orce is pro5ided !"coupling uphill and downhill mo5ement o# one or more solutewhich is a #a5ora!le electrochemical gradient exists 0eg seesaw4
• Cotransporters 0/"mporters4
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o Intrinsic mem!rane proteins that mo5e the
dri5ing solute 0gradient pro5ides the energ"4and dri5en solutes 0which mo5e uphill4 in thesame direction
• Exchangers 09ntiporters4
Examples o# Cotransporters
• Na)1lucose Cotransporter 0/1L$4o Located at apical mem!rane o# cells that line
the PC$ and /mall Intestineo elongs to the /LC7 #amil" consisting o# a
single su!unit /1L$M = mo5es < Na with each
glucose molecule /1L$< and . = mo5e M Na with each
gluose
• Na-@ri5en Cotransporters #or 3rganic /oluteso Na-@ri5en 99 $ransporters = !elong to /LCV
and /LC.X Na-coupled cotransporter #or
%onocar!ox"latesJ @i and $ri
• Na)HC3. Cotransporterso elongs to /LCQR ;e"group o# acid-!ase
transporters 06egulation o# intracellular pH4o In the !asolateral mem!ranes
Electrogenic = EZux o# HC3. M.
0NaHC3.4 Electroneutral = Inux o# HC3. MM
• Na-@ri5en Cotransporters #or Inorganic 9nionso NaPi = mem!ers o# /LC MWJ < and .Q and
/ul#ate cotransporter 0/LCM.4
• Na)K)Cl Cotransportero elong to /LCM<o Harness energ" o# the inwardl" directed Na+
electrochemical gradient to dri5e theaccumulation o# Cl and K
NKCCM = present in the !asolateral
mem!rane NKCC< = present in the apical
mem!raneo %ediate the uphill Cl transport to cell
o Inhi!ited !" #urosemide and !umetanide which
are called Loop @iuretics !ec the" increaseurine ow !" inhi!iting transport at loop o#Henle
• Na)Cl Cotransportero In the apical mem!rane o# @C$o K+ independentR !loc;ed !" thiaide diuretics
• K)Cl Cotransportero Na-independentR
o Electrochemical gradient is outwardl" directed
!ec it is means to accumulate in the cell
o K Electrochemical gradient is outwardl"directed !ec it is means to accumulate in thecell mo5ing K and Cl inward
o Inside gradient mem!rane potential causes
eZux o# Cl NKKC
Cl-HC3.
• ring Cl into the cell
• Cl Electrochemical gradient isoutwardl" directed !ec it ismeans to accumulate in thecell
• H-@ri5en Cotransporters
o H)oligopeptide cotransporter Pep$M and related
proteins are mem!ers o# /LCM7o Pep$M D electrogenic and responsi!le #or upta;e
o# small peptides #rom the lumen into the cellso# renal PC$ and small intestine
o %ediate the electroneutralJ H-couple ux o#
lactateJ p"ru5ate or other monocar!ox"latesacross the cell mem!ranes o# most tissues o#the !od"
H-dri5en 9mino 9cid Cotransporters
0ex P9$M4D mem!ers o# /LC.V %onocar!ox"late Cotransporter 0ex
%C$M4• Can operate in either the net
inward or outward directionJdepending on the lactate andH gradients across the cellmem!rane
• %o5es lactate out o# cells thatproduce lactate !" gl"col"sis!ut into cells that consumelactate
o @i5alent %etal Ion Cotransporter 0@%$M4
%em!er o# /LCM
Couples the inux o# H to the inux o#
Ferrous Iron 0Fe<+4 as well as to a5ariet" o# other di5alent mealsJ someo# which 0Cd<+J P!<+4 are toxic to cells
Expressed at high le5els in ;idne" and
proximal part o# the /mall Intestine
Exchangers Another Class o Secondary Active(ransporters Exchange o *ons or One Another
3ther ma&or class o# secondar" acti5e transporters is theexchangersJ or antiporters
• Exchangers D intrinsic mem!rane proteins that mo5eone or more :dri5ing[ solutes in one direction and one ormore :dri5en[ solutes in the opposite directionR --exchanges anion #or anion and cation #or cation
o Na-Ca Exchanger
Nearl" u!i(uitous Na-Ca Exchanger0NC4 !elong to /LCX
%ediate the exchange o# .M 0NaCa4
Electrogenic and mo5es net powsiti5e
charge in the same direction as Na Na 0inuxR as primar" 9$4 = Ca 0eZuxR
as secondar" 9$4o Na-H Exchanger 0NHE4
/LC 0MM4
Na 0inux4 H 0eZux4 = pH o# Cell
• NHEMo present in
nonepithelial cellsand !asolateralmem!ranes o#epithelia
o pla"s ma&or role inpHi regulation andcell 5olume
• NHE.o Present at apical
mem!ranes o#se5eral epithelia
o Pla"s ma&or role in
acid secretion or Naa!sorption
3rganic Cation H Exchanger
• /ecretes cationic meta!olitesand drugs across the apical
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mem!rane o# renal proximaltu!ule cells and hepatoc"tes
o Na @ri5en Cl-HC3. Exchanger 0N@CE4
Important #or pHi regulation
/LCQ mem!er 0MM<4
2ses inwardl" directed Na
electrochemical gradient to dri5euphill entr" o# HC3. into the cell
o Cl-HC3. Exchanger
In5ol5ed in acid-!ase transport that
#xs independentl" o# Na %em!ers o# either /LCQ or /LC<V 0MM4
0/LCQ4 9nion Exchangers 09EM-9E.4
• 9EM = Important #or transport
o# HC3. into the 6C in thelung and out o# the 6C inperipheral tissues
• 9E< and .o Inwardl" directed Cl
gradient almostalwa"s dri5es out o#the cellR pla"s a rolein cell 5olumeregulation
0/LC<V4
• Pla" important roles inepithelial Cl and HC3.
transport
• multi#unctionalo 3ther 9nion Exchangers
Cl-Formate Exchange 0CFE4 and Cl-
3xalate Exchange
• Present in the apical
mem!ranes o# renal PC$• Important #or the secondar"
acti5e upta;e o# Cl Pendrin = mediates Cl-HC3. exchange
and transports I\which is important inthe th"roid gland
3rganic 9nion $ransporting
Pol"peptides 039$P4
• %em!ers o# /LC<M
• %ediates the upta;e o# !ile
acidsJ !iliru!in and the testsu!strate !romosulphthaleinin the li5er
Prostaglandin $ransporter 0P1$4
• %ediates the upta;e o#prostanoids
• 0eg, prostaglandins E< and F<a and throm!oxane <4
3rganic 9nion $ransporters 039$4
• /LC<<
• %ediate the upta;e o#endogenous organic anions!" exchange or #acilitateddi>usion
6egulation o *ntracellular *on Concentrations
(he #a+. Pump .eeps #a inside the Cell 7o5 and . High
Inhi!ited !" 3299IN ] Nai rises and K i #alls
Pla"s important role in generating the inside-negati5emem!rane 5oltage ] 0VmA4 in a t"pical cell
9ccomplishes in two wa"so .< 0NaK4 ] Electrogenic = causing outward
current o# positi5e charge across the plasmamem!rane
o 9cti5e K accumulation creates a conc gradient
that #a5ors exit o# K #rom cell through Kchannels
he tendency o# 4 to e-it through these channels, withunmatched negative charges le#t behind, is the main cause o# the
inside8negative membrane voltage. or this reason Na9sinwardly directed Na6electrochemical gradient allows passive
entry o# Na
o /odium 0Na4
Predominant in ECF at MQ7m% in Conc
1radient is maintained !" acti5eextrusion o# Na #rom cell !" Na-KPump
o Potassium 0K4
Q,7m% in ECFR predominant in ICF
a!out <7-. #old Its channel is inhi!ited such as a<+
and Am !ecomes less negati5e 0celldepolaries4
Cell Harness the Na Energ" #or $hree %a&or PurposesM, In certain epithelial cellsJ amiloride-sensiti5e Na
channels 0ENaC4 are largel" restricted to the apical orluminal sur#ace o# cell, Na-K pumps are restricted to the!asolateral sur#ace o# the cell, In this wa"Jtransepithelial Na transport ta;es place than a #utilerec"cling o# Na !ac; and #orth across a single plasmamem!rane
<, In e-citable cellsJ passi5e entr" o# Na entr" occursthrough 5oltage-dependent Na channels and pla"scritical role in generation o# action potential, Na is c"cledat high energ" cost across the plasma mem!rane #orimportant ph"siological purpose o# in#ormation trans#er
., Airtuall" e5er" cell in the !od" tissues uses Na gradientacross plasma mem!rane to dri5e the second acti5etransport o# nutrients and ions
Ca8% Pump and the #a+Ca Exchanger .eep *ntracellular Ca Four Orders o )agnitude 7o5er than EC Ca
• EC Ca ] Mm%J IC Mn% = Conc 1radient M-#old
• rought !" Aoltage-1ated Ion Channelo Ca<+ Pumps 0/E6C94 in 3rganelle %em!ranes
Ca pumps 09$Pases4 are present on
mem!ranes that surrounds 5arious ICorganelles such as sarcoplasmicreticulum and E6
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9cti5el" se(uester c"tosolic Ca in IC
stores then released into thec"toplasm in !ursts as part o# signaltransduction process in response tomem!rane depolariation or humoralagents
o Ca Pump 0P%C94 on the Plasma %em!rane
%a&or route o# Ca extrusion
Pump itsel# is incapa!le o# this t"pe o#
#eed!ac; control !ecause it has a highKm #or Cai,
9s Cai risesJ the Ca !inds to a protein
called calmodulin which has a highanit" to Ca,
Newl" #ormed Ca-Ca% !inds to Ca
PumpJ lowers the pumps Km #or Ca i into the ph"siological range and thusstimulates Ca extrusion
Cai #alls = Ca-Ca% le5els IC #alls so Ca-
Ca% dissociates #rom Ca pumpJreturning pump to its inacti5e stateresulting Mn% at resting state
o Na-Ca Exchanger 0NC4 on Plasma %em!rane
For Ca eZux onl" when Cai rises
a!o5e normal le5els Important in restoring low Cai when
large inuxes o# Ca occur Contri!utes to the excita!le cells Aia Aoltage-1ated Ca Channels
*n )ost Cells Cl is )osdestly A$ove E"uili$rium BecauseCl 9pta:e $y Cl+HCO; Exchanger and #a-.-ClCotransporter Balances Passive Cl E<ux (hroughChannels
• Chlorideo OICFR ECFo Can passi5el" pass through mem!rane !ecause
o# the cells anion-selecti5e channelso VmA inside-negati5e mem!rane 5oltage
• Cl-HC3. Exchanger = most common pathwa" #or Clupta;e
•
Na)K)Cl Cotransportero mediate uphill Cl transporto Passi5e extrusion o# Cl through anion-selecti5e
channels in P% opposes Cl upta;e machanisms
• K)Cl Cotransporter
#a+H Exchanger and #a+4riven HCO; (ransporters .eepthe *ntracellular pH and HCO; A$ove (heir E"uili$rium
• 9cid Extruders = secondar" acti5e transporters that are
energied !" the electrochemical Na gradient across thecell mem!rane
o /ensiti5e to pHi changes
o /timulied when acidicR Inhi!ited i# al;alinied
ICFo Important Extruders
Na-@ri5en Cl-HC3. Exchangers 0M<4
Na)HC3. Cotransporters 0MM4
o Important 9cid/ecretors
A-t"pe H
H-K Pumps
• 9cid Loaders = !alance acid extrusion
=ater (ransport and the 6egulation o Cell /olume=ater (ransport is 4riven $y Osmotic and HydrostaticPressure 4iference Across )em$ranes
• 9lwa"s passi5e
• L3B FL2I@I$^ = L3BE6 H<3 PE6%E9ILI$^ due topresence o# phospholipids and long chains o# #att" acidswith #ew dou!le !onds
• /ingle water molecules can dissol5e in lipid !ila"ers _mo5e across cell mem!ranes at a low !ut ?nite rate !"simple di>usion
• Ease o# H<3 di>uses through lipid !ila"er depends onlipid composition o# !ila"er
929P36IN/ 09PM4
• /pecialie water channels that ser5e as a passi5e
conduits o# water transport
• Its presence increases mem!rane water permea!ilit"
• ollecting duct cells o# 3idney regulate the H2O
permeability o# their apical membranes by inserting 1$P2 water channels into their apical membrancesunder control o# 1(!ININ" and V1*OP("**IN
• Er"throc"tes or renal proximal tu!uleJ 9PM is alwa"spresent in mem!rane
Net @ri5ing Force
• < @ri5ing Forceso Chemical Potential Energ" @i>erence = water
conc dependent to the two sides o# themem!rane
o Energ" di>erenceJ per mole o# waterJ that
results #rom the di>erence in H^@63/$9$ICP6E//226E 0`H<3J pressure4 across the mem!rane
P = h"drostatic pressure Aw = partial morlar 5olume o# H<3
• 3/%3L9LI$^o concentration o# osmoticall" acti5e solutes
o 2NI$ osmoles);g o# H<3
• Colloid 3smotic Pressure)3ncotic Pressureo @i>erence in osmotic pressure that tends
pull!ac; o# uid
• 2ltra?ltrationo $he resulting mo5ement o# water out o# the
capillar" when h"drostatic pressure di>erenceexceeds the colloid osmotic pressure di>erence
Because o the Presence o *mpermeant #egativelyCharged Proteins =ithin the Cell 4O#A# FO6CES =ill7ead to Cell S5elling
Na-K Pump 9!sence = /BELLIN1
%odel NE19$IAEL^ CH961E@J I%PE6%E9N$%9C63%3LEC2LE/
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