підручники. біохімія / Uchebnik_po_Biokhimii_E_S_Severin

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6-24).

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3. Pezy.llllU,UR ofJw,ew nymu Kama60.r1U3.Ma

CKopocTh CMHTe3a ATcD CTporo coorneTcrnyeT 3HepreT~eCK11M nOTPe6HOCTHM KJieTK11. 3To ,UOCT11raeTC51 cornacosaHHOti pery;rnutteti scex 3rnnoB 3aKJI10q11TeJibHOro nYTM Karn60JI113Ma, BKJIJ0qa10mero npeBpamettMe nttpyBarn B aueT11JIKoA, UMTpaTHbiti u11KJI 11 UIT3. 8 6oJiblllMHcrne TKatteti, r,LI.e rnasttaH cPYHKUM5l o6mero ITYTM Karn60JI113Ma - o6ecneqeHMe KJieTK11 3Heprneti, Ba)lrny10 poJih B peryJIBu1111 11rpaeT ,LI.bIXaTeJibHbiti KOHTPOJib.

YseJI11qeHMe cKopocTM YT11J1maum1 ATcD ,LI.JIH coseprueH11S1 pa3JIMqHblX B11,UOB pa60TbI yseJIMqMBaeT KOHUeHTpaUMIO A,lJ,cD, qTo yCKOp51eT OK11CJieHMe NADH B UIT3 M, cJie.uosaTeJibHO, noBhirnaeT cKopocTb peaKu11ti, KaTaJI113MpyeMhIX NAD-3aB11- c11MbIM11 ,LI.er11,LI.poretta3aMM. OK11cJieHMe nttpysarn M aueTMJI-KoA MO)J(eT np011CXO,U11Tb TOJibKO B TOM cJiyY.ae, ecJI11 3JieKTPOHbI 11 npoTOHbI OT NADH M FADH 2 noCTyna10T B UIT3. TaKMM o6pa3oM, oTHoweHMH A,lJ,cD/ATcD 11 NADH/NAD+ - rnaBHbie MO,UyJIHTOpbi CKOpOCTM peaKU11H o6mero ITYTM Karn60JTM3Ma (OITK).

KaK 113BeCTHO, cKopoCTh Mern6o;rnqecKMX nYTeti, KOTOpb1e .uoJI)[(HbJ o6ecneqMBaTb nocTOHHHbiti yposeHh KOHeY.HbIX npo.uyKTOB, TaKMX, KaK ATcD, pery;rnpyeTCH Ha ypostte peaKu11ti, KaTan11311pyeMbIX peryJIHTOPHhIMM ¢epMeHrnMM. Ha 3aKJnoqMTeJibHOM 3rnne Karn60JI113Ma Ha1160Jiee Ba)J(Hbie peryJimopHbie ¢epMeHTbI - n11pysaT,LI.ern,LI.poreHa3HbIH KOMIlJieKc, u11TPaTc11Hrn3a, 1130U11TPaT,LI.er11,LI.poreHa3a 11 CX-KeTOfJIYTapaT,LI.er11,L1.poretta3HbIH KOMITJieKC.

NADH<!>

A1..1eTl'1Jl-KoA@

Perymm,us nupYBaT,LI.erH)J,poreualuoro KOMDJieKca.

PeryJIHU11H Ha yposHe IT.UK 11MeeT Ba)J(HOe 3HaqeHMe ,LI.JI51 o6ecneY.eHM51 U11TpaTHOfO UMKJia «TOnJIMBHblM11» MoJieKYJiaMtt aueT11J1KoA.

06pa3oBaHMe aueT11JIKoA tt3 rr11pysarn - Heo6paTMMbiti KJIJOqesoti 3TaIT Mern60JI113Ma. )i(}isoTHbie He crroco6HhI K npeBpameHMJO aueT11JI-KoA s fJIIOK03y. AKTMBHOCTb rr11pyBaT,LI.er11,L1.poretta3HOfO KOMnJieKca peryJI11pyeTcS1 pa3;mqHbIMM cnoco6aMtt: ,UOCTyITHOCTblO cy6CTPaTOB, 11Hrn611poBaH11eM rrpo,LI.YKTaMM peaKuw11, aJTJIOCTepwqecK11 11 ITYTeM KOBaJieHTHOH MO.Utt¢11Kau1111.

KoBaJieHTHa51 MO,LI.11¢11Kau11S1 IT.UK ocymecrnJI51eTc51 ¢oc¢op11J1ttpoBatt11eM 11 ,LI.e¢oc¢op11JI11poBaHtteM. B cocrnB IT)],K BXO.U51T 2 peryJI51TOPHhIX cy6be,LI.11H11Ubl. 0.uHa 113 H11x, KMHa3a IT)],K, ¢oc- ¢op11JIMpyeT IT)],K B orrpe.ueJieHHhix yY.aCTKax no ocrnTKaM cep11Ha. Ilp11 ¢oc¢opmrnposaH11tt IT)],K 11HaKT11BMpyeTC51. )],pyra51 peryJI51TOpHa51 cy6be,LI.M- H11Ua, ¢oc¢arn3a, .ue¢oc¢op11JI11pyeT ¢epMeHT, npespama51 ero B aKT11BHYJO ¢opMy (p11c. 6-26).

ITpM IlOBbillleH11M KOHUeHTpau11M A,lJ,cD n)],K HaXO,U11TC51 B He¢oc¢opMJIMPOBaHHOH aKTMBHOH ¢opMe. 3TOT 3¢¢eKT yc11JittBaeTc5J B HeKoTOpbIX KJieTKax nptt nOBbillleH1111 KOHUeHTPaUM11 BHYTPMKJieToqHoro Ca2+, KOTOpbiti aKTMB11pyeT ¢oc¢arn3y Il)],K. TaKoti MexaHM3M aKTMBaUMM IT.UK oco6ettHo Ba)J(eH B MbllUUaX 11 )1(11p0BOH TKaHM.

ITpo,LI.yKTbI rr11pyBamer11,L1.poreHa3HOti peaKUtttt (aueTMJI-KoA M NADH) aJTJIOCTep11qecK11 aKT11BMpy10T KMHa3y Il)],K. AKT11B11posaHHaH K11Ha3a ¢oc- ¢op11n11pyeT 11 MHaKT11s11pyeT Il.ll,K. TaK11M o6pa30M, npM HaKorrJieHMM NADH w aueTttJI-KoA TOPM03MTCH npespameHMe rr11pysarn B aueTMJIKoA. TaKaH c11Tyautt5l co3.uaeTc5J, Hanp11Mep, B

nHpyeaT

rreqeHH npH fOJIO)J,aHHH: H3 )l(lfpOBhIX )J,erro B rreqeHb TlOCTYTiaJOT :)(<HpHbie KHCJIOTbl, H3 KOTOpbIX o6pa3yeTrn aueTHJIKoA. B npttcyrcTBHH BhICOKoMoJieKyJI51pHhIX .IKHPHhIX KHCJIOT HHrH6HpOBam1e Il,LJ,K ycttmrnaeTC51. OttpyBaT rrptt 3TOM He oKHcJI51eTc51 H MO)l(eT 6hJTh HCT10Jlb30BaH )J,JI51 CHHTe3a fJIJOK03bl (CM. pa3)J,eJI 7).

OttpyBaT aJIJIOCTepttqecKH aKTHBttpyeT He<PoccpopHJI.11poBaHttyJO cpopMy O,!lK, )J,eti:CTBY51 COfJia-

COBaHHO c JlPYrHMH cy6cTpaTaMH - NAD+ H KoA.

AKTHBau1rn Il)J,K rrpottcxo)J,HT TaK.IKe no)], BJIH51HHeM HHCYJIHHa. 0)1,HH H3 3cpcpeKTOB HHCYJIHHa - IlOBbJllleHHe KOHUeHTpaUHH BHYTPHMHTOXOHJlPHaJibHOfO Ca2+. Ilptt rroBhillleHHH KOHUeHTpaum1 Ca2+ O)J,K aKTHBHpyeTC51 (cM. pttc. 3ToT Me-

xaHH3M oco6eHHO Ba)!(eH B )l(HpOBOH TKaHH, me aueTHJIKoA Heo6xo)J,HM )J,JI5I CHHTe3a )l(lfPHhIX KHCJIOT (CM. pa3)J,eJI 8). B KJieTKaX MHOKap)J,a Il)J,K aKTHBHpyeTC51 a)J,peHaJIHHOM, O)J,HaKO 3TO BJIH51HHe a)J,peHaJIHHa He CB513aHO c H3MeHeHHeM KOHUeHTpaUHH uAM<l>.

PeryJUIIUtB IUtTpaTuoro IUtKJia. B 6oJihllIHHCTBe CJiyqaeB CKOpOCTb peaKUHH B MeTa6oJIHqecKHX

UHKJiax orrpe)J,em1eTC5I HX HaqaJibHbIMH peaKUH51MH. B UTK B~eti:lllaJI peryn51Toptta51 peaKUH51 -

o6pa3oBaHtte UHTparn H3 OKCMoauernrn H aueTHJIKoA, KaTaJIH3HpyeM<l}I UHTpaTCHHTa3oti:. 3rn peaKUHH ycKOp51eTC51 rrpH IlOBbillleHHH KOHUeHTpaUHH OKCaJioaueTaTa - cy6cTpaTa peaKUHH H TOPM03HTC51 rrpo)J,yKTOM peaKUHH - UHTpaTOM. Koma OTHorneHHe NADH/NAD+ CHH)!(aeTcH, cKopocTh OKHCJieHIDI MaJiaTa B OKCaJioauernT B03pacTaeT. IlOBbIWeHHe KOHUeHTpaUHH OKCaJioaueTaTa ycKop51eT UHTpaTCHHTa3HYJO peaKUHJO. CKopocTh peaKUHH CHH)!(aeTC51 rrpH TlOBbllIIeHHH KOHUeHTpaUHH AT<l>, CYKUHHHJI-KoA H MHHHouerroqeqHhIX )!(lfpHbIX KHCJIOT. 0)1,HaKO TOqHhlH MexaHH3M BJIH51Hll51 3THX MeTa6oJIHTOB Ha UHTpaTCHHTa3Y He- )J,OCTaTO'fHO51CeH (pHC. 6-27).

1130UHTpaT)J,erll)J,pOreHa3a, OJIHfOMepHblH cpepMeHT, COCTOIIT H3 8 cy6be)J,HHHU. IlpHCOe)J,HHeHHe 1130UHTpaTa K rrepBoti: cy6be)J,HHHUe Bbl3bIBaeT KOorrepaTHBHOe H3MeHeHHe KOHcpOpMaUHH JlPYfHX, yBeJIH'fHBa51 CKOpOCTb rrpttcoe)J,HHeHH51 cy6cTparn. <l>epMeHT aJIJIOCTep11qecKH aKTHBHpyeTC51 A)],<l> H Ca2+, KoTOpb1e npttcoe)J,HH51JOTC51 K cpepMeHTY B pa3HhIX aJIJIOCTepHYecK11x ueHTpax. B rrpttcyTCTBHH A)],<D KOHcpopMaUH51 Bcex cy6be)J,HHHU MeH51eTC51 TaKHM o6pa30M, 'ITOCB513bIBaHHe H30UHTpaTa rrpoHCXO)J,HT 3HaqttTeJibHO 6blcTpee. TaKHM o6pa30M, npH KOHUeHTpauHH H30UHTpaTa, KOTOpa51 CYllieCTBy-

eT B MllTOXOHJlPllaJibHOM MaTpHKCe, He60JibWHe H3MeHeHH51 KOHUeHTpau1111 A)],<l> MOfYT Bhl3BaTh 3HalfttTeJihHOe H3MeHeH11e cKopocTH peaKUHH. YBeJI11qett11e aKTIIBHOCTll 1130UHTpaT)J,erH)J,pOreHa3hl CHlf)!(aeT KOHUeHTpauHJO UHTparn, 'ITO,B CBOJO Olfepe)J,h, YMeHblllaeT HHrn611poBaHHe UHTpaTCHHTa3hI rrpO)J,yKTOM peaKUHH. IlpH IlOBbIWeHHH KOHUeHTpau11H NADH aKTHBHOCTh cpepMeHrn CHH)!(aeTc51.

a- KeTornyrnpaT)J,er11)J,poreHa3HbIH KOMrrJieKc, HMeJOIUHH CXO)J,HOe CTpOeHHe c TlllpYBamerll)J,p0reHa3HbIM, B OTJIII'flleOT ITOCJie)J,Hero, He HMeeT B CBOeM COCTaBe peryJI51TOpHbIX cy6be)J,HHHU. f JiaBHblH MexaHH3M peryJI51UHH a-KeTOrnyrapaT)J,erll)J,- poreHa3HOf0 KOMrrJieKca - 11Hrn611poBaH11e peaKUHH NADH H CYKUHHHJI-KoA.

a- KeTornyrnpaT)J,ertt)J,poreHa3HhIH KOMITJieKc, KaK H 1130UHTpaT)J,er11)J,poreHa3a, aKTHBHpyeTC51 Ca2+, a rrptt rroBhillleHHH KOHUeHTpau11H AT<D cKopocTH o6eHX peaKUHH CHJl)!(aJOTC51.

B peryJI51UHH u11TpaTHoro u11KJia cymecrnyeT MHO)!(eCTBO )J,OTlOJIHHTeJibHbIX MexaHH3MOB, o6ecrrelfHBaJOIUHX Heo6xomtMhI:ti: ypoBeHh Mern6oJIHTOB II IIX yqacTHe B JlPYfllX MeTa6oJIHqecKHX ITYT5IX.

KoMnapTMeHTaJIH3aUH51 cpepMeHTOB, yyacTBYJOIUHX B peaKU1151X OKHCJIHTe:1bHOfO )J,eKap6oKCHJIHPOBaHH5:l nttpysarn H UHKJia JIHMOHHOH KHCJIOThl, HrpaeT Ba)!(HyJO pOJib B peryJI51UHH 3TIIX npouecCOB.

BHyrpeHHHH MeM6paHa MHTOXOHJlpHi1 HerrpoHttuaeMa )J,JI51 aHHOHOB H KaTHOHOB, B TOM lfllCJie H

)J,JI5I rrpoMe)!(yrOqHbIX npO)J,yKTOB UHTpaTHOfO UHKJia, KOTOpb1e MOfYT 6bITb nepeHeceHhI Yepe3 MeM6paHy TOJihKO rrpH ylfaCTHH crreUHaJihHbIX 6eJIKOB. Ilo3TOMY <PepMeHTbl UHTpaTHOro UHKJia HMeJOT 60JihWe B03MO)l(HOCTeH )J,JI51 B3aHMO)J,eHCTBH51 c npo)J,yKTaMH npe)J,hl)J,YWHX peaKUHH, lfeM B CJiylfae cB06o)J,ttoro YJlaJieHHH 3THX rrpo)J,yKTOB H3 MHTOXOH)J,p.11.ii.

)J,OCTYITHOCTh cy6cTpaTOB B03pacrneT TaK.IKe B pe3yJihTaTe o6pa30BaHH51 cpepMeHTHbIX KOMITJieKCOB. MMaT)J,ertt)J,poretta3a .11. UHTpaTCl1HTa3a o6pa3yJOT HerrpO'IHbieKOMITJieKChl, B KOTOpbIX UHTpaTCHHTa3a MO)!(eT HCilOJib30BaTb OKCaJioaueTaT, Herrocpe)J,CTBeHHO o6pa3yJOW.11.HC51 MaJiaT)J,erH)J,p0reHa3oti:.

B n)J,K H a-KeTOrnyrapaT)J,erll)J,poreHa3HOM KOMTIJieKce cy6cTpaThI Herrocpe)J,CTBeHHO rrepe)J,aJOTC51 OT O)J,HOfO cpepMeHrn K JlPYrDMy: TOJibKO TpaHcaUHJia3a MO)l(eT B3aHMO)J,eHCTBOBaTb c rrpoMe~Olf­

HhIM rrpo)J,yKTOM, CBH3aHHhIM c T)J,<D, a )J,ttrnnpo-

JIHTIOH.JI,UenmporeHa3a - c )l,Hfl1,l.lpOJII.fTIOeBOH KI.fC-

JIOTOH.

NAO+, NADH, KoA, auenrn-KoA 11 cyKUHHI.fJI-

KoA He HMelOT TpaHcnopTHhIX 6eJIKOB B MeM6pa-

He Ml1TOXOH)l.ptttl:. Il03TOMY 3Tl1 coe)l.HHeHl15I He

MOryT npotl:TH qepe3 MHTOXOH)l.pHaJihHYIO MeM6-

paHy.

HaKonneH11e aul.fJI-KoA npott3BO)l.HhIX, rnK11x

KaK aueTHJI-KoA I.fJIH CYKUHHI.fJI-KoA, B Ml1TOXOH-

)l.pHaJihHOM MaTp11KCe 11Hrtt6ttpyeT )l.pyrtte peaK-

UHH, )l.Jl5I KOTOphIX tteo6xo)l,HM KoA.

TecHa5I CB5I3h UHTpaTHOro UHKJia 11 UI13 no)l.-

)l.ep)[<HBaeTcH 6naro)l,apH HCTIOJlh30BaH11IO B 3THX

peaKUirnx o6w.ero ¢oH)l.a NAO+ n NADH.

B. AllAEoJI11qEcKHE <t>YHKIJ,1111 QllTPATHoro

QllKJIA

UnKJI JIHMOHttotl: KMCJIOThI - O)l.HH H3 aM¢n6onwqecKHx TIYTetl: Mern6oJIH3Ma. B tteM ocymecrnJI5I10TC5I He TOJihKO OKMCJIHTeJibHhie npeBpameHH5I 3HepreTnqecKHx cy6CTPaTOB )l,0 KOHel.JHhIX ilpO)l.yK-

TOB co2 l1 H20, HO l1 rrpol1CXO,IJ;HT o6pa30Bam1e cy6cTpaTOB )]JIH ,n:pyrl1x MeTa6on11qecKl1X rryTeil (pl1C. 6-28).

HeKOTOpb1e npoMe)l()"ToqHbie npo.n;yKTbI UttKJia JIHMOHHOH KHCJIOTbI: 0.-KeTornyTapaT, CYKUHHaT, OKCaJioaueTaT MOryr HCI10Jlh30BaTbCH )]JISI CHHTe3a 3aMeHHMbIX aMHHOKHCJIOT (CM. pa3.n;en 9).

Y6hmh npoMe)l()"ToqHhIX npo,n:yKTOB UHKJia BOCnoJIHHeTcsr B peaKUHHX, KaTaJIH3HpyeMblX cneul1 - q:mqecKl1Ml1 $epMeHTaMl1. B HOPMaJihHbIX ycnoBl1SIX peaKUHl1, OTBJieKaIOIUHe npoMe)l(yTO'lHbie rrpo,n:yKTbl H3 UHKJia H BOCI10JlH5110lliHe HX y6hillb, HaxO,llSITCH B COCTOHHHH ,llHHaMHqecKOfO paBHOBeCHH, TaK qTo KOHUeHTpauHH 3THX rrpo,n:yKTOB B MHTOXOH,llpHHX OCTaeTCH IlOCTOHHHOH.

PeaKUHH, 06ecneq11Ba10mtte rrononHeH11e <PoH- ,n:a npoMe)l()"TO'lHblXrrpO,lJ)'KTOBI.J,TK, Ha3bIBalOTCH aHal1JlepoT11'leCKHMH(norronHHIOWHMH). Ba)l(Hettmasr 113 HHX - peaKUHH cwme3a oKcaJJ.oauernrn H3 JIHPYBaTa. 3ry peaKUMIO KaTaJIH3MpyeT MHTOXOH,llpMaJJ.bHblll <PepMeHT - JIHpyBaTKap6oKCHJia3a.

3HHa, Haxo,n:HmerocH B aKTHBHOM ueHrpe <:PepMeHTa (pHC. 6-29).

EcnH ,llJlH UHKJia JIHMOHHOH KMCJIOTbI He XBarneT oKcanoaueTaTa ttJIH KaKoro-Htt6y.n;h .n;pyroro npoMe)l(YTO'lHOfOnpo,n:yKTa, TO Kap60KCHJIHpOBaHl1e rrttpYBaTa ycKopHeTcH. B 3Toil peaKUHH B Ka- 'leCTBeHCTO'lHHKa3HeprnH HCITOJih3yeTCH AT<l>.

PeaKUHH npoTeKaeT B 2 crn,n:HH. Ha rrepBott crn-

.IlHH ITpOHCXO,llHT aKTHBaUHSI C02 JIYTeM ITplICOe-

,llHHeHHH K O,llHOMY H3 aTOMOB a30Ta B MOJieKyJie

6ttOTHHa. 3Ta peaKUHH COilpH)l(eHa c fH,llpOJIH30M

AT<l>.

AT<l> + C02+ E-6HOTHH +Hp~ A,LJ,<l> + H3P04 + E-6HOTHH-COO- + 2 H+.

Ha Brnpow cTa.n;Htt aKTHBHpoBaHHasr Kap6oKCHJibHasr rpyrrna nepeHOCHTCH Ha nttpyBaT.

E-6HOTHH-COO- + nwpyBaT ~ E-6HOTHH + 0KcanoauernT.

rrttpyBaT- > CH3 - CO - COOH + C02 + AT<l>Kap6oKcHJiaJa

HOOC - CO - CH2 - COOH + A,LJ,<l> + H 3P04.

CTttpyBaTKap6oKcHJia3a - CJIO)l(Hhltt onwroMepHhIH $epMeHT. MoneKYJia <:PepMeHTa co,n:ep)l(HT 4 npOCTeT11qecKHe rpyrrrrhI, rrpe.n;CTaBJieHHbie 6HOTHHOM (CM. pa3,n:en 3), KOTOphill KOBaJieHTHO CBSI3aH aMH,IJ;HOH CBH3bl0 c £-aMHHOrpynrraMH OCTaTKOB JIH-

IlwpyBaTKap6oKcHJia3a - perynHTOpHbIH <:PepMeHT. Ecnw KOHUeHrpaUHH aueTHJI-KoA yBeJIII'lHBaeTcsr, TO OH .n;ewcrnyeT KaK aJIJIOCTepwqecKHH aKTHBaTop nMpYBaTKap6oKcHJia3hI, ycKopHH o6pa30BaHtte oKcanoauernrn. TaKHM o6pa30M, H36bITOK aueTHJI-KoA crroco6crnyeT aKTHBauim UHTpaTHoro UHKJia.

Mern6oJIHThI UlfTPaTHoro UHKJia 11cnoJih3YIQTCH He TOJlhKO KaK cy6cTpaTbl CHHTe3a yrnepo.n;Horo

CKeJJeTa p}l)la coe;:urneHMH, HO H HBJUIIOTCH ,[(OHOpaMH BO):(OpO,[(a LI.JUI o6pa308aHHH 80CCTaHOBJ1eHHbIX Ko<PepMeHT08, yqaCTBYfOlll,HX 8 peaKUHHX CHHTe3a )[(ttpHbIX KHCJJOT, cTepoauo8 w ):(pymx 8emecTB (cM. pa3,[(eJ1hI 8, 10, 11). )J,8a Mern6oJIMTa UMTpaTttoro UHKJ1a MOryT ,[(erH):(pttpoBaThCH rrpw yYaCTMM NADP-3a8vtCHMhIX ,[(erH):(poretta3: Manarn w 1130uvtTParn. HanpHMep, MaJJaT MO)KeT rrocwnaTb 113 MHTOXOH,Uptttl: 8 UHT030Jlh KJieTKM. B IIHT030Jie HaXO,[(HTC51 NADP-3a8HCHMaH ,[(erauporetta3a (MaJJHK- <PepMeHT), KaTa.Hl13Hpy10maH peaKIIHIO:

HOOC - CHOH - CH 2 - COOH + NADP+

MaJJHK-)

¢epMettT CH3 - CO·COOH + C02 + NADPHr

ManaT w H30UHTpaT o6ecneYtt8aIOT o6pa3o8atttte oKOJTO rroJT08HHhI o6IUero ct>oaua NADPH, 11cnoJTh3yeMoro 8 80CCTaH08HTeJTbHhIX CHHTe3ax; 8TOpa51 ITOJT08HHa 06pa3yeTCH 8 rreHT03o<Poc¢aTHOM nyTH npe8pametttt51 rJIIOK03hI (cM. pa3,[(eJT 7).

f. fHII03HEPfETJlqECKHE COCTO.HHll.H

Bee )l(l18ble KJieTKH ITOCTOHHHO H~aIOTC51 8

ATct> MH ocylLl,eCTBJJetttt51 pa3JTHYHhIX 811.UOB )[(tt3-

tte):(e51TeJihHOCTH.

KJieTKM M03ra ITOTpe6JIHIOT 60JiblllOe KOJIHYeCTBO AT<D M51 cwttTe3a ttetl:poMemrnTopoB, pereHepauw11 HepBHbIX KJieTOK, ITOMep)l(aHH51 Heo6xo- ,[(11MOfO rpa,[(ttettTa Na+ w K+, MH npo8e,[(eHHH ttepsttoro HMITYJihca; nOYKH wcrrOJih3YIOT AT<D 8 npouecce pea6cop6u1111 pa3JlttYHhIX 8emecTB rrpw o6pa30BaHHH MOYH; 8 neYeHH rrpOHCXO,[(HT CHHTe3 rJIHKOretta, )KHP08, 6eJIK08 l1 MHOfHX ):(pymx co- e;:itttteHtttl:; 8 MHOKap):(e ITOCT051HHO C08epwaeTCH MexaHHYecKaH pa6orn, tteo6xo,[(11MaH M51 uttpKyJIHUHH Kp08tt; CKeJieTHbie MbIWLl,hl B ITOKOe noTpe6JIHIOT tte3HaY11TeJTbtthre KOJIHYeCT8a A T<D, HO npw cPH3HYeCKOH Harpy3Ke 3Tl1 ITOTpe6HOCTH 803pacTaIOT 8 ):(eCH.TKH pa3 (Ta6J1. 6-6).

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