留學(xué)生上課教案講稿及urinary1yp

1、Urinary System Dept. of Anat., Hist. & Embry. Hainan medical collegeYueping Li1. General description1.1 Componentskidneys ureters urinary bladder urethra1.2 FunctionProduces & delivers urineRegulates the balance of water, electrolytes & acid-baseSecretes hormones, bioactive substances (renin, EPO, 1

2、,25-(OH)2D3, etc.)Objective1234to grasp the organisation of the kidneyto know the structure of juxtaglomerular complex andt its fuctunction to know the function of the renal interstitiumto grasp the structures and functions of the nephron.2.1 Genaral structureFibrous capsuleparenchyma Cortex Medulla

3、：renal pyramidscortical labyrinth medullary rays2. Kidneysmedulla rayscortex labyrinthcortexmedullaHistology structure of kidney Nephron Renal corpuscle（cortical labyrinth ） Renal tubule collecting tubule (medullary rays、renal pyramids) Juxtaglomerular complexNephroncollecting ductJuxaglomerular com

4、plex/apparatus2.2 NephronComponents & positionRenal corpuscleRenal tubuleGlomerulusRenal capsuleProximal tubuleThin segmentDistal tubuleconvoluted, straightconvolutedstraight Nephron loop ( Henles loop)(1) Renal corpuscle Present in the cortexSpherical in shapeMade up of glomerulus & renal capsuleHa

5、s vascular pole & urinary poleGlomerulusAfferent arteriolecapillary loopsefferent arterioleFenestrated capillaries, resting on thick basement membrane Capillaries supported by mesangium = mesangial cells + matrixGlomerulus-mesangial cellsThe entire structure is the renal corpuscle. The blue structur

6、e (A) is the Bowmans capsule (2 and 3). The pink structure is the glomerulus with its capillaries. At the left, blood flows from the afferent areteriole (9), through the capillaries (10), and out the efferent arteriole (11). The mesangium is the pink structure inside the glomerulus between the capil

7、laries (5a) and extending outside the glomerulus (5b)Glomerulus-mesangial cellsMesangial cells are usually divided into two types, each having a very distinct function and location: Extraglomerular mesangial cells Intraglomerular mesangial cellsGlomerulus-mesangial cells Extraglomerular mesangial ce

8、lls Extraglomerular mesangial cells are light-staining pericytes in the kidneyfound outside the glomerulus, near the vascular pole. They resemble smooth muscle cells and play a role in renal utoregulation of blood flow to the kidney and regulation of systemic blood pressure through the Renin-Angiote

9、nsin-Aldosterone system. The specific function of extraglomerular mesangial cells is not well understood, although it has been associated with the secretion of erythropoietin.1 1.Junqueira, Luiz C.; Jose Carneiro (2003). Basic Histology. McGraw-Hill. ISBN 0-8385-0590-2.Glomerulus-mesangial cells Int

10、raglomerular mesangial cells Intraglomerular mesangial cells are specialized pericytes located among the glomerular capillaries within a renal corpuscle of a kidney. There are three primary functions of intraglomerular mesangial cells: filtration, structural support, and phagocytosis. Additionally,

11、mesangial cells are able to monitor glucose levels via processes sent into the capillary lumen.Renal (Bowmans) capsuleDouble-layer cup of epitheliumOuter or parietal layer is squamousInner or visceral layer covers capillaries & is formed by podocytesIn between is urinary (Bowmans) spaceSecondary pro

12、cesses interdigitate & wrap around cap. Slit pore (25nm) & slit membrane (4-6nm thick) PodocytesLarge cells with pale-stained nucleus Primary processes secondary processesFiltration membrane (barrier)Fenestrated endothelium Glomerular basement membraneSlit membrane of podocytesFunctionProducing filt

13、rate (primary urine) through filtration Filtration membrane(In high-powered transmission EM) Filtration membrane(In high-powered transmission EM)(1) Renal tubule Proximal (convoluted) tubuleLocated in cortex around its parent renal corpuscleLongest & thickest segment with small, irregular lumenLMSim

14、ple cuboidal acidophilic cells, large & deep-stainedBrush border on free surface indistinct lateral margin basal longitudinal striations EMMicrovilli on free sufaceInterdigited lateral processesPlasma membrane infoldings & mitochondria in basal partion Function - main reabsorption siteAll nutrients,

15、 most of water & ions (Na+)Secreting H+ , creatinine, etc.The structure and function ofproximal convoluted tubule Thin segment Thin with small lumen Lined with squamous epitheliumPermeable to water and ionsComponent of Henles loop to generate hypertonic urineLocated in cortex Thinner than proximal t

16、ubule with relative large lumenLMSimple cuboidal cells, small & light stainedDistal (convoluted) tubuleNo brush border; well-developed basal longitudinal striations EMSparse microvilli on free sufaceInterdigited lateral processesAbundant basal membrane infoldings & mitochondria Function Absorption o

17、f water regulated by antidiuretic hormoneAbsorption of Na+ & excretion of K+ regulated by aldosteroneSecretion of H+ & NH31SECTION您的內(nèi)容請(qǐng)寫在這里您的內(nèi)容13proximal tubule and distal tubule2.3 Collecting duct systemComponents Arched, cortical, medullary collecting duct & papillary ductStructureLined by simple

18、cuboidal to columnar cellsCytoplasm is lightly stainedDistinct intercellular boundariesFunction: Similar to distal convoluted tubule adjusted by the same hormonesCollecting ductLocation: at vascular pole ComponentsJuxtaglomerular cellsMacula densaExtraglomerular mesangial cells2.4 Juxtaglomerular complex (apparatus)Juxtaglomerular cellsModified SMCs in wall of afferent arteriolesCuboidal basophilic cells with round nucleus Contain secretory granules of reninMacula densaSpecialized region of distal tubule adjacent to vascular poleHi