組織學(xué)與胚胎學(xué)14 泌尿系統(tǒng)(中英)

UrinarySystemKidney腎Ureter輸尿管Urinarybladder膀胱Kidney腎A.Introduction:1.Generalstructure:

Eachkidneyhasaconcaveborder,thehilum,wherebloodvesselsandureterexitandcommunicatethekidney.Therenalpelvis,theexpandedupperendoftheureter,branchesandrebranchesintomajorcalycesandminorcalyces.2.Capsule被膜:

CTcontainingrichfatcells.

3.Cortex:皮質(zhì)Mainlylocatesatperipherywiththerenalcolumn腎柱,thepillar-shapedcortexthatexistsbetweenpyramid-likemedulla.4.Medulla髓質(zhì):Centrallylocated10~18pyramid-likestructuresknownasrenalpyramids

（腎椎體）,whosebasesradiallysendoutthe

medullaryrays髓放線thatseparatethecortexintocorticallabyrinth

（皮質(zhì)迷路）.腎葉：

每個腎錐體及與其相連的皮質(zhì)腎小葉：

每個髓放線及其周圍的皮質(zhì)迷路5.Kidneycontainsnumerousuriniferoustubules泌尿小管,whicharecomposedofnephrons腎單位andcollectingtubules集合管.6.Nephron腎單位:Thestructuralandfunctionalunitofkidney.renalcorpuscle腎小體:renalglomerulus+glomeruluscapsuleb.renaltubule腎小管:

proximalconvolutedtubules(C)+Henle’sloop+distalconvolutedtubules(C).7.Functionsofkidney:

Clearanceofmetabolismwastesinbloodstream;

RegulationofminerallevelandpHvalueinbody.Nephron（腎單位）Renalcorpuscle（腎小體）Renaltubule（腎小管）Proximaltubule～convolutedtubule～straighttubuleThinsegmentDistaltubule～straighttubule～convolutedtubuleMedullaryloop腎單位nephron腎小體（Renalcorpuscle

）

血管球腎小囊腎小管（Renaltubule

）近端小管～曲部～直部細段遠端小管～直部～曲部髓袢Corticalnephron（皮質(zhì)~）85%，shortloopformationofurineJuxtamedullarynephron（髓旁~）15%，longloopConcentrateurine1.

Renalcorpuscle

（腎小體）

:

Theplacewherethebloodisfilteredtoformpre-urine.Hasvascularpole血管極,wheretheafferentarteriole入球微Aentersandthinnerefferentarteriole出球微Aleavesrenalcorpuscle,andurinarypole尿極,wheretheproximalconvolutedtubuleleavesthecorpuscle.renalglomerulus(血管球):

anastomizingfenestratedCaps

有孔毛細血管withoutdiaphragm.permeability↑,havecontinuousbasementmembrane

？Mesangium(血管系膜，球內(nèi)系膜）

Intraglomerularmesangialcell球內(nèi)系膜細胞LM：smallanddarknucleus，undistinguishedfromothercellsEM：Processes：mayprotrudebetweenendotheliumandbasementmembrane。abundantorganelles：rER、Golgi、lysosome、phagocytoticvesicles、microtubule、microfilamentmesangialmatrix系膜基質(zhì)Function：1、synthesizebasementmembraneandmesangialmatrix合成基膜和基質(zhì)2、phagocytosis吞噬基膜上的沉淀物，維持通透性3、participateinrenovationofthebasementmembrane參與基膜更新4、cellcontraction→controlbloodstreamofglomus控制血管球血流量。b.glomeruluscapsule腎小囊(Bowman'scapsule):parietallayer壁層:

linedbysimplesquamousepithelium.capsularspace腎小囊腔thespacesbetweenthe2layers.viscerallayer臟層:composedof

podocytes(足細胞）包繞在血管球毛細血管外面LM：undistinguishedwithothercellsEM：body→severalprimaryprocesses初級突起→

numeroussecondaryprocesses次級突起;Filtrationslits(裂孔）:spacesbetweensecondaryprocesses,25nm。Slitmembrane(裂孔膜):4～6nmPodocyte

Glomerularbasementmembrane血管球基膜thickerthangeneralbasementmembrane，about330nm。3layers，middlelayerthickandcompact，othersthinandloose。IVcollagen、laminin

（層粘連蛋白）、proteoglycan阻止血漿帶負電荷的物質(zhì)通過，防止血漿蛋白濾出。透射電鏡

whichisabout0.1μmthick.Permeableforsubstanceswhosemoleculeweightarelessthan70kDa.fluidthatpassedfiltrationmembraneintocapsularspacenamedpro-urine原尿（180L/d;125ml/m).Filtrationmembrane

濾過膜blood-urine

barrierfiltrationbarrier:composedofendothelia,basementmembraneand

slitmembrane裂孔膜,通過濾過膜流到腎小囊腔的液體稱原尿（180L/d;125ml/min)。濾過膜受損：蛋白質(zhì)通過→蛋白尿紅細胞通過→血尿Renaltubule腎小管單層上皮性小管，近端接腎小囊，遠端接集合管，有重吸收原尿中大部分成分和排泄的作用，分：近端小管proximaltubule

細段thinsegment

遠端小管distaltubuleproximalconvolutedtubule（近曲小管）

LM：LocatedincorticallabyrinthsorrenalcolumnsSmallandirregularlumen;large,cuboidalcellswithundistinguishedboundariesAcidophilicBrushborder刷狀緣

Basalstriations縱紋

EM：microvilli微絨毛

（brushborderunderLM）abundantplasmamembraneinfolding質(zhì)膜內(nèi)褶

（光鏡下縱紋）andmitochondrialateralextensions側(cè)突

cellmembranedepressed→smallvesiclesandtubuleslysosome、phagocytoticvesicles。Locatedinmedullaryrayandrenalpyramid,thestructuresimilartoproximalconvolutedtubule.EM：lower，microvilli、lateralextensionsandplasmamembraneinfolding↓↓Functionofproximaltubule：Reabsorb：85%H2O、nearlytotalglucose葡萄糖、aminoacid氨基酸；aswellas65%Na+and50%urea尿素。Secrete:H+、ammonia氨、creatinine(肌酐)andhippuricacid(馬尿酸)etal。2）.proximalstaighttubule（近直小管）LM：locatedinmedullaryrayandrenalpyramidthin;simplesquamousepithelium。

weakacidophilic3)Thinsegment細段EM：fewmicrovilli、plasmamembraneinfolding，organells。Function：有利于水和離子通過4）Distalstaighttubule（遠直小管）LM：Locatedinmedullaryrayandrenalpyramidsimplecuboidalepithelium,distinguishedcellboundaries；pale-stainedplasma；nobrushborderBasalstriationsEM：plasmamembraneinfoldingsandmitochondria基部質(zhì)膜上有豐富的Na＋、K＋-ATP酶，能主動向間質(zhì)轉(zhuǎn)運Na＋，細胞膜還可能有一種呈凝狀不通透水的酸性糖蛋白，致使水不能通過，因此造成從腎錐體底至腎乳頭的間質(zhì)內(nèi)的滲透壓逐步增高，有利于集合小系對水的重吸收。5）convolutedtubule（遠曲小管）Locatedincorticallabyrinths，similartodistalstraighttubule,afewBasalstriations遠曲小管是離子交換的重要部位，細胞有吸收水、Na＋和排出K＋、H＋、NH3等作用，對維持體液的酸堿平衡起重要作用。Adjustbyaldosterone醛固酮

andantidiureticH抗利尿激素使尿液濃縮，尿量減少

Functionofdistaltubule:ContinuereabsorbH2OandNa+Secrete:K+、H+andammoniaetal，tomaintainacid－baseandelectrolureequilibrationofbodyfluid近曲小管與遠曲小管光鏡結(jié)構(gòu)的區(qū)別遠曲小管近曲小管胞質(zhì)嗜酸性弱、色淡強、色深細胞分界清楚不清楚管壁與管腔壁薄、細胞小，腔大而規(guī)則壁厚、細胞大，腔小而不規(guī)則刷狀緣無明顯基底縱紋不清楚清楚Arched～→straight～→papillarySimplecuboidal→columnar,pale-stainedplasma,distinguishedcellboundaries,neuclousroundandcentral-locatedReabsorbH2OandNa+，SecreteK+，NH3，

adjustbyaldosterone醛固酮

andantidiureticH抗利尿激素.C.Collectingtubuleandduct集合小管:

Juxtaglomerularapparatus球旁復(fù)合體:

Locateatvascularpoles.有球旁細胞、球外系膜細胞和致密斑排成三角形，入球微動脈和出球微動脈構(gòu)成三角形的兩邊，致密斑構(gòu)成底邊，球外系膜細胞位于三角區(qū)的中心。juxtaglomerularcell球旁細胞LM:Afferentarteriole入球微動脈

Smoothmusclecells↓EM:rib、rERGolgiSecreteGFunction:

renin

腎素。angiotensinogen血管緊張素原

angiotensinIangiotensinIIbloodvesselcontractbloodpressure↑aldosterone醛固酮↑bloodvolum↑,bloodpressure↑reninEpithelium–likecell:large,cuboidal,basophilicMaculadensa致密斑Location:distaltubule,nearthevassularpoleLM：high,narrow,closenucleus→topEM：base→smallprocessdiscontinuousbasementmembrane。Function：Na+receptor離子感受器

感受遠端小管內(nèi)濾液的Na＋濃度變化。當(dāng)濾液內(nèi)Na＋濃度降低時，致密斑細胞將“信息”傳遞給球旁細胞，促進球旁細胞分泌腎素，增強遠端小管儲Na＋排K＋作用。

3.Extraglomerularcells:球外系膜細胞LocatebetweenmaculadensaandBowman’scapsule.Havegapjunctionswithmesangialcellsandjuxtaglomerularcells.可能傳遞信息.4.peripolarcell

極周細胞腎小囊壁層轉(zhuǎn)折為臟層處細胞內(nèi)含膜包顆粒釋放入腎小囊腔，調(diào)節(jié)腎小管的重吸收和分泌功能腎的血液循環(huán)血液循環(huán)的主要通路

腎A

腎V葉間A

直小V

葉間V弓形A

球后毛細血管網(wǎng)

弓形V小葉間A

直小A

小葉間V

入球微A

球后毛細血管網(wǎng)腎小球毛細血管網(wǎng)

出球微A特點：腎動脈起源于腹主動脈，血流量大，4-5分鐘濾過一遍。兩次形成毛細血管網(wǎng)，球后毛細血管網(wǎng)膠體滲透壓高，有利于腎小管