腎臟泌尿功能的調(diào)節(jié)課件

第三節(jié)腎臟泌尿功能的調(diào)節(jié)

Regulationofurineformationofthekidney尿生成的調(diào)節(jié)

regulationofurineformation腎血流量的調(diào)節(jié) 神經(jīng)—體液調(diào)節(jié)

regulationofrenalbloodflownervousandhumonalcontrol(對(duì)濾過的調(diào)節(jié)) (對(duì)重吸收和分泌) 自身神經(jīng)體液 調(diào)節(jié)調(diào)節(jié)調(diào)節(jié)ADH醛固酮甲狀旁腺素Aldosteroneparathyroidhormone

作用：1.提高遠(yuǎn)曲小管和集合管上皮細(xì)胞對(duì)水的通透性，促進(jìn)水的重吸收尿液濃縮、尿量減少（抗利尿）[主要作用]。ThemostimportantrenalactionofADHistoincreasethewaterpermeabilityofthedistaltubule,collectingtubule.Thiseffecthelpsthebodytoconservewaterincircumstancessuchasdehydration.2.增加內(nèi)髓部集合管對(duì)尿素的通透性并減少腎髓質(zhì)的血流量。ADHincreasestheureapermeabilityofcollectingtubuleininnerzoneanddecreasesthebloodflowinmedulla.3.促進(jìn)髓絆升支粗段對(duì)NaCl的重吸收，使直小血管收縮。ADHincreasesthereabsorptionofNaClinthicksegmentofascendinglimbandsoleadstoconstrictionofvasarecta.（一）、作用機(jī)理：ADH與遠(yuǎn)曲小管、集合管上皮細(xì)胞管周膜上受體結(jié)合激活膜內(nèi)的腺苷酸環(huán)化酶上皮細(xì)胞中cAMP管腔膜中蛋白激酶激活膜蛋白磷酸化膜構(gòu)型改變水通道開放管腔膜對(duì)水通透性。ADH，水通道小泡內(nèi)移，對(duì)水通透性。

ADHcombineswiththereceptorinbasolateralmembraneandactivatedtheadenylatecyclase,itproducescyclicadenosinemonophosphate,whichleadstoactivationofproteinkinaseinbasolateralmembrane,thenthemembraneproteinisphosphorylated,sotheconfigurationofmembranechanges,thisprocessincreasesthepermeabilitytowaterbytheopenofwaterchannel.1、血漿晶體滲透壓的改變特點(diǎn)：敏感，晶體滲透壓改變1～2%時(shí)即有反應(yīng)。電解質(zhì)(+)有效尿素?zé)o效感受器：位于視上核及其附近區(qū)域。大量出汗、腹瀉、失水血漿晶體滲透壓視上核及其周圍區(qū)域滲透壓感受器(+)神經(jīng)垂體膨大神經(jīng)末梢去極化釋放ADH遠(yuǎn)曲小管、集合管對(duì)水通透性對(duì)水重吸收，尿液濃縮尿量減少。TheprecisewaythattheosmoticconcentrationoftheextracellularfluidscontrolsADHsecretionisnotclear.Yetsomewhereinornearthehypothalamusaremodifiedneuronreceptorscalledosmoreceptors.whentheextracellularfluidbecomestooconcentrated,fluidispulledbyosmosisoutoftheosmoreceptorcell,initiatingappropriatenervesignalsinthehypothalamustocauseadditionalADHsecretion.

水利尿waterdiuresis大量飲清水尿量飲1000ml清水，隔30分鐘尿量，（1小時(shí)末達(dá)高峰，2—3小時(shí)恢復(fù)）飲1000mlNS，隔30分鐘變化不大

2、循環(huán)血量的改變（容量感受器途徑）

過度輸液，血量過多(+)左心房?jī)?nèi)膜下容量感受器

迷走N，傳入沖動(dòng)中樞，間接抑制下丘腦—垂體后葉系統(tǒng)釋放ADH遠(yuǎn)曲小管集合管對(duì)水通透性對(duì)水重吸收尿量。Whenbloodvolumeincreasesbecauseofexcesstransfuse,thevolumereceptorinendometriumofleftatriumsendsimpulsethroughVagusnervetocenterandinhibitthereleaseofADHbyHypothalami-Pituitaryposteriorlobesystem,sothewaterpermeabilityindistaltubuleandcollectingtubuledecreases,thereforethereaborptionofwaterdecreasesandtheurinevolumeincreases.二、醛固酮的作用（Aldosterone）分泌部位：腎上腺皮質(zhì)球狀帶靶器官：遠(yuǎn)曲小管集合管作用：促進(jìn)對(duì)Na+的主動(dòng)重吸收，同時(shí)促進(jìn) K+的排出——保Na+排K+作用。Aldosterone,secretedbythezonaglomerulosecellsoftheadrenalcortex,isanimportantregulatorofsodiumreabsorptionandpotassiumsecretionbytherenaltubules.Theprimarysiteofaldosteroneactionisontheprincipalcellsofthecorticalcollectingtubule.themechanismbywhichaldosteroneincreasesodiumreabsorptionwhileatthesametimeincreasingpotassiumsecretionisstimulatingthesodium-potassiumATPasepumponthebasolateralsideofthecorticalcollectingtubulemembrane.（一）作用機(jī)制：醛固酮進(jìn)入遠(yuǎn)曲小管集合管的上皮細(xì)胞后與胞漿受體結(jié)合形成激素—胞漿受體復(fù)合物通過核膜與核中受體結(jié)合激素—核受體復(fù)合物促進(jìn)mRNA的合成醛固酮 促進(jìn)小管上皮細(xì)胞Na+

泵運(yùn)轉(zhuǎn)誘導(dǎo)蛋白 促進(jìn)生化氧化提供ATP促進(jìn)加強(qiáng)Na+

增加管腔膜對(duì)Na+

通透性的主動(dòng)重吸收(保Na+)造成小管腔內(nèi)負(fù)電位K+被分泌到小管液（排K+)Aldosteronediffusesreadilytotheinteriorofthetubulaarepithelialcellsandcombineswithahighlyspecificcytoplasmicreceptorprotein,thenthealdosterone-receptorcomplexdiffusesintothenucleuswhereitmayundergofurtheralterations,finallyinducingoneormorespecificportionsoftheDNAtoformoneormoretypesofmessengerRNArelatedtotheprocessofsodiumandpotassiumtransport.（心房利尿肽ANP）28個(gè)氨基酸殘基集合管對(duì)Na+重吸收(-)，使出入球小動(dòng)脈舒張心鈉素（Cardionatrin）(-)aldosterone釋放

ADH

腎素分泌作用：促進(jìn)腎臟排鈉排水Thefunctionofcardionatrinistopromotethesecretionofsodiumandwaterbykidney.thecardionatrincanreducethereleaseofaldosterone、ADHandrenin.（二）醛固酮分泌的調(diào)節(jié)：腎素—血管緊張素—醛固酮系統(tǒng)、血K+、血Na+濃度促腎上腺皮質(zhì)激素（ACTH）對(duì)醛固酮分泌的日常調(diào)節(jié)不起重要作用

Potassiumionconcentrationandtherenin-angiotensinsystemarebyfarthemostpotentinregulatingaldosteronesecretion.1.腎素—血管緊張素—醛固酮系統(tǒng)（renin-angiotensin-aldosteronesystem,RAAS）RAA系統(tǒng)的活性取決于血漿中腎素濃度，故凡能影響腎素分泌的因素均可間接影響醛固酮的分泌。肝硬化繼發(fā)性醛固酮增多癥水腫、腹水組織液循環(huán)血量腎素醛固酮cirrhosisofliversecondaryaldosteronismEdema、Hydroperitoniatissuefluidbloodvolumereninaldosterone三、甲狀旁腺激素(parathyroidhormone,PTH)

的作用分泌部位：甲狀旁腺作用：1.促進(jìn)遠(yuǎn)球小管和集合管對(duì)Ca2+的重吸收，減少尿Ca2+排出量；2.抑制近球小管對(duì)磷酸鹽的重吸收，增加尿中磷酸鹽的排出量；3.抑制近球小管對(duì)Na+、K+、HCO3-和氨基酸的重吸收。PTHissecrectedbyparathyroidglands.PTHprovidesapowerfulmechanismforcontrollingextracellularcalciumandphosphateconcentrationsbyregulatingintestinalreabsorption,renalexcretion,andexchangebetweentheextracellularfluidandboneoftheseions.PTHdecreasescalciumexcretionandincreasesphosphateexcretionbythekidneys.moreover,itincreasestherateofreabsorptionofmagnesiumionsandhydrogenionswhileitdecreasesthereabsorptionofsodium,potassium,andaminoacidions.第四節(jié)血漿清除率plasmaclearance腎功能測(cè)量方法(useofclearancemethodstoquantifykidneyfunction)：1.尿濃縮和稀釋試驗(yàn)(UrineconcentrationtestandUrinedilutiontest)——反映腎小管功能2.酚紅排泄試驗(yàn)(excretiontestofphenolsulfonphthalein)——反映腎小管功能3.血漿清除率試驗(yàn)(plasmaclearancetest)—反映腎小球?yàn)V過率、腎血流量尿濃縮試驗(yàn)——主要測(cè)定腎小管對(duì)水重吸收功能 正常濃縮功能尿比重可達(dá)1.030Urineconcentrationtestmainlyquantifiesthereabsorptiontowaterofrenaltubule.尿稀釋試驗(yàn)——測(cè)定多水情況下尿液變淡程度正常成人短時(shí)間內(nèi)飲水1～1.5L，尿比重可<1.003Urinedilutiontestmainlyquantifiesthedilutiondegreeofurine.酚紅排泄試驗(yàn)——反映腎小管的分泌排泄功能0.6%酚紅1ml靜脈注射15分鐘排泄出注入量25%以上 2小時(shí)排泄出注入量60%以上 病理：15分鐘<12% 2小時(shí)<40%

1.腎小球?yàn)V過率的測(cè)定：菊粉清除率、內(nèi)生肌酐清除率菊粉inulin濾過后，既不被重吸收也不被分泌，故測(cè)定菊粉的血漿清除率可代表腎小球?yàn)V過率。

U·V1ml/min×125mg/100mlC菊粉===125ml/min

P1mg/100mlInulinclearancecanbuusedtoestimateGFR.inulinisfreelyfilteredandisnotreabsorbedorsecretedbytherenaltubules,therateatwhichthatinulinisexcretedintheurine(U*V)isequaltothefiltrationrateofthesubstancebythekidneys(GFR*p),theGFR,therefore,canbecalculatedastheclearanceoftheinulin.2.腎血流量的測(cè)定(estimationofrenalplasmaflow)碘銳特diodrast、對(duì)氨基馬尿酸（PAH）靜脈注射后，經(jīng)腎循環(huán)一周后可完全清除掉（通過濾過和分泌）。即在腎動(dòng)脈中該物質(zhì)有一定濃度，流到腎靜脈中其濃度接近0，那么該物質(zhì)每分鐘的尿中排出量（U·V），應(yīng)等于每分鐘通過腎臟的血漿中所含的量，該物質(zhì)血漿清除率為每分鐘通過腎臟的血漿量。

Theorectically,ifasubstanceiscompletelyclearedfromthelasma,theclearancerateofthatsubstanceisequaltothetotalrenalplasmaflow,inotherwords,theamountofthesubstancedeliveredtothekidneysinthebloodwouldbeequaltotheamountexcretedintheurine.Thus,renalplasmaflowcouldbecalculatedasRPF=U*V/p.第五節(jié)尿的排放(micturition)一、輸尿管(ureter)的運(yùn)動(dòng)輸尿管連接腎盂(pelvis)處平滑肌細(xì)胞有自律性(autorhythmicity)，興奮下傳產(chǎn)生蠕動(dòng)波3次/min，其推進(jìn)速度2-—3cm/s。腎盂中尿量越多，內(nèi)壓越大，自動(dòng)節(jié)律性頻率越高，蠕動(dòng)增強(qiáng)，反之亦然。尿因輸尿管蠕動(dòng)，一陣陣被推入膀胱(bladder)。二、膀胱和尿道的神經(jīng)支配

盆Npelvicnerves

傳入傳出副交感NS2—4三對(duì)N腹下NHypogastricnerves

傳入傳出交感NL1—5

陰部Npudendalnerve

傳入傳出軀體NS2—4受意識(shí)控制

傳入纖維傳出纖維盆N膀胱充脹感覺膀胱逼尿肌收縮、膀胱內(nèi)括約肌舒張促排尿腹下N傳導(dǎo)膀胱痛覺膀胱逼尿肌松弛、膀胱內(nèi)括約肌收縮阻止排尿陰部N傳導(dǎo)尿道感覺尿道外括約肌收縮阻止排尿（受意識(shí)和反射控制）

三、排尿反射(micturitionreflex)膀胱內(nèi)壓當(dāng)尿量>400ml才明顯提高當(dāng)尿量達(dá)到700ml時(shí)，內(nèi)壓為35cmH2O，逼尿肌(detrusormuscles)產(chǎn)生節(jié)律收縮，排尿欲增高。內(nèi)壓達(dá)到70cmH2O時(shí)產(chǎn)生痛感，不得不排尿

Intravesicalpressureevidentlyincreaseswhentheurinevolumeismorethan400millilitre.排尿反射micturitionreflex：

腦干、皮層高位中樞膀胱尿量膀胱壁牽骶髓排尿反射盆N膀胱逼尿肌收縮400～500ml張感受器初級(jí)中樞內(nèi)括約肌松弛

尿液入后尿道排尿

Whenurinevolume