Slide Pleno 1.5

GROUP 19:Debby Mulya RahmyNopriyanti Eka PratiwiIrawati Fauziah FiskaRadhia Ashabul Kahfi BeyRadhiatul MardhiahRuslan KamilSuhayatra PutraWira Lestiani ArifWulan Octaviani

1ST WEEK

Copyright 2008 Pearson Education, Inc., publishing as Benjamin CummingsLEARNING OBJECTIVESEmbryology of Urinary SystemAnatomy of Urinary SystemHystology of Urinary SystemVascularization & Innervation of Urinary SystemCongenital Disorder of Urinary System

Urogenital SystemFunctionally the urogenital system can be divided into two entirely different components: The urinary system The genital system. Embryologically and anatomically they are intimately interwoven. Both develop from a common mesodermal ridge (intermediate mesoderm)Initially the excretory ducts of both systems enter a common cavity, the cloaca.

Urinary SystemKIDNEY SYSTEMSThree slightly overlapping kidney systems are formed in a cranial to caudal sequence during intrauterine life in humans: The pronephros, (rudimentary and nonfunctional).The mesonephros, (function for a short time during the early fetal period).The metanephros, (forms the permanent kidney)

PronephrosAt the beginning of the fourth week, the pronephros is represented by 7 to 10 solid cell groups in the cervical region. These groups form vestigial excretory units, nephrotomes, that regress before more caudal ones are formed. By the end of the fourth week, all indications of the pronephric system have disappeared.

Relationship of the intermediate mesoderm of the pronephric, mesonephric,and metanephric systems. In cervical and upper thoracic regions intermediatemesoderm is segmented; in lower thoracic, lumbar, and sacral regions it forms a solid,unsegmented mass of tissue, the nephrogenic cord.Note the longitudinal collectingduct, formed initially by the pronephros but later by the mesonephrosUnsegmented mesoderm(metanephric system)

MesonephrosThe mesonephros and mesonephric ducts are derived from intermediate mesoderm from upper thoracic to upper lumbar (L3) segments. Early in the fourth week, the first excretory tubules of the mesonephros appear. They lengthen rapidly, form an S-shaped loop, and acquire a tuft of capillaries that will form a glomerulus at their medial extremity. Around the glomerulus the tubules form Bowmans capsule, and together these structures constitute a renal corpuscle. Laterally the tubule enters the longitudinal collecting duct known as the mesonephric or wolffian duct.

In the middle of the second month the mesonephros forms a large ovoid organ on each side of the midline. Since the developing gonad is on its medial side, the ridge formed by both organs is known as the urogenital ridge.The caudal tubules are still differentiating, The cranial tubules and glomeruli show degenerative changes, and by the end of the second month the majority have disappeared. In the male a few of the caudal tubules and the mesonephric duct persist and participate in formation of the genital system, but they disappear in the female.

MetanephrosThe Definitive KidneyThe third urinary organ, the metanephros, or permanent kidney, appears in the fifth week.Its excretory units develop from metanephric mesoderm in the same manner as in the mesonephric system. The development of the duct system differs from that of the other kidney systems.

Development of the renal pelvis, calyces, andcollecting tubules of the metanephros. Note the pyramid form of the collecting tubules entering the minor calyx.6 weeksend of 6th week7 weeksNewborn

Collecting SystemCollecting ducts of the permanent kidney develop from the ureteric bud.The bud dilates, forming the primitive renal pelvis, and splits into cranial and caudal portions (the future major calyces). Each calyx forms two new buds while penetrating the metanephric tissue.Meanwhile, at the periphery more tubules form until the end of the fifth month.The tubules of the second order enlarge and absorb those of the third and fourth generations, forming the minor calyces of the renal pelvis.Collecting tubules of the fifth and successive generations form the renal pyramid.

metanephric excretory unit Development

Excretory SystemEach newly formed collecting tubule is covered at its distal end by a metanephric tissue cap. Cells of the tissue cap form small vesicles, the renal vesicles, Renal vesicles give rise to small S-shaped tubules. Capillaries grow into the pocket at one end of the S and differentiate into glomeruli. These tubules, together with their glomeruli, form nephrons, or excretory units. The proximal end of each nephron forms Bowmans capsule. The distal end forms an open connection with one of the collecting tubules, establishing a passageway from Bowmans capsule to the collecting unit. Continuous lengthening of the excretory tubule results in formation of the proximal convoluted tubule, loop of Henle, and distal convoluted tubule.

The kidney develops from two sources: (a) metanephric mesoderm, which provides excretory units.(b) the ureteric bud, which gives rise to the collecting system.

POSITION OF THE KIDNEYThe kidney, initially in the pelvic region, later shifts to a more cranial position in the abdomen.This ascent of the kidney is caused by diminution of body curvature and by growth of the body in the lumbar and sacral regions. In the pelvis the metanephros receives its arterial supply from a pelvic branch of the aorta. During its ascent to the abdominal level, it is vascularized by arteries that originate from the aorta at continuously higher levels. The lower vessels usually degenerate, but some may remain.

FUNCTION OF THE KIDNEYThe definitive kidney formed from the metanephros becomes functional near the 12th week. Urine is passed into the amniotic cavity and mixes with the amniotic fluid. The fluid is swallowed by the fetus and recycles through the kidneys. During fetal life, the kidneys are not responsible for excretion of waste products, The placenta serves this function.

BLADDER AND URETHRADuring the fourth to seventh weeks of development the cloaca divides into the urogenital sinus anteriorly and the anal canal posteriorly. The urorectal septum is a layer of mesoderm between the primitive anal canal and the urogenital sinus. The tip of the septum will form the perineal body. Three portions of the urogenital sinus can be distinguished:The urinary bladder , (the upper and largest part).The pelvic part of the urogenital sinus, (narrow canal)The phallic part of the urogenital sinus,(flattened from side to side).

Initially the bladder is continuous with the allantois, but when the lumen of the allantois is obliterated, the urachus, remains and connects the apex of the bladder with the umbilicus.In the adult, it is known as the median umbilical ligament.The next part is a narrow canal, the pelvic part of the urogenital sinus, In the male gives rise to the prostatic and membranous parts of the urethra.The last part is the phallic part of the urogenital sinus. It is flattened from side to side, and as the genital tubercle grows, this part of the sinus will be pulled ventrally.BLADDER AND URETHRA

During Differentiation of the CloacaThe caudal portions of the mesonephric ducts are absorbed into the wall of the urinary bladder. The ureters enter the bladder separately. As a result of ascent of the kidneys, the orifices of the ureters move farther cranially; those of the mesonephric ducts move close together to enter the prostatic urethra and in the male become the ejaculatory ducts. The mucosa of the bladder formed by incorporation of the ducts (the trigone of the bladder) is also mesodermal.With time the mesodermal lining of the trigone is replaced by endodermal epithelium, so that finally the inside of the bladder is completely lined with endodermal epithelium.

Dorsal views of the bladder showing the relation of the ureters and mesonephric ducts during development(A) Initially the ureters are formed by an outgrowth of the mesonephric duct(BD) with time they assume a separate entrance into the urinary bladder(C and D)the trigone of the bladder formed by incorporation of the mesonephric ducts.

URETHRAThe epithelium of the urethra in both sexes originates in the endoderm; At the end of the third month, epithelium of the prostatic urethra begins to proliferate and forms a number of outgrowths that penetrate the surrounding mesenchyme. In the male, these buds form the prostate gland . In the female, the cranial part of the urethra gives rise to the urethral and paraurethral glands.

Copyright 2008 Pearson Education, Inc., publishing as Benjamin CummingsLocation and External Anatomy of KidneysLocated retroperitoneallyLateral to T12L3 vertebrae Average kidney12 cm tall, 6 cm wide, 3 cm thickHilusOn concave surface Vessels and nerves enter and exitRenal capsule surrounds the kidney

Copyright 2008 Pearson Education, Inc., publishing as Benjamin CummingsInternal Anatomy of the KidneysFrontal section through the kidneyRenal cortexRenal pyramidsRenal pelvisMajor caliciesMinor caliciesGross vasculatureRenal arteriesBranch into segmental arteries

UreterUrine, which is formed within the nephrons, flows into the ureter, a long fibromuscular tube that connects each kidney to the bladder.The ureters are narrow, muscular tubes, each 24 to 30 cm long, that originate at the lower portion of the renal pelvis and terminate in the trigone of the bladder wall.

Copyright 2008 Pearson Education, Inc., publishing as Benjamin Cummings

UreterThere are three narrowed areas of each ureter: ureteropelvic junction ureteral segmentureterovesical junction

Copyright 2008 Pearson Education, Inc., publishing as Benjamin Cummings

Copyright 2008 Pearson Education, Inc., publishing as Benjamin CummingsUrinary BladderA collapsible muscular sacStores and expels urineFull bladder sphericalExpands into the abdominal cavityEmpty bladder lies entirely within the pelvisFigure 23.13

Copyright 2008 Pearson Education, Inc., publishing as Benjamin CummingsFigure 23.14Urinary BladderUrachus closed remnant of the allantois Prostate glandIn malesLies directly inferior to the bladderSurrounds the urethra

Copyright 2008 Pearson Education, Inc., publishing as Benjamin CummingsUrethraIn femalesLength of 34 cmIn males 20 cm in length three named regionsProstatic urethraPasses through the prostate glandMembranous urethraThrough the urogenital diaphragm Spongy (penile) urethraPasses through the length of the penis

Kidney & NephronsThe human kidney has about four million filtering units callednephrons:The renal corpuscle: glomerulus and Bowman capsuleProximal convoluted tubules (PCT, located in the renal cortex)Descending loop of Henle (LOH)Ascending limb (which resides in the renal medulla, leading to the thick ascending limb)Thick ascending limbDistal convoluted tubuleCollecting duct (which opens into the renal papilla)

Blood from the afferent glomerular arteriole passes through the juxtamedullary apparatus to the glomerulus.The glomerulus is a network of capillaries that filters blood across Bowman capsule into the proximal convoluted tubule.The glomerulus contains podocytes and a basement membrane allowing water and certain solutes to be filtered across.

PCT reabsorbs glucose and various electrolytes along with water as the filtrate passes through. After being filtered at the glomerulus, the blood passes into the efferent glomerular arteriole and then descends into the renal pyramid.

UreterThe ureter is roughly 3-4 mm in diameter. Ureter is lined with transitional cell epithelium, which consists of a short basal layer.The thickest layer of the ureter is the muscularis, which is composed of smooth muscles oriented in an inner longitudinal and outer circular arrangement.The outer portion of the ureter is the adventitia, a fibrous layer that harbors the vascular supply.

BladderThe bladder mucosa is transitional epithelium, which is loosely connected to the muscular wall by way of a connective tissue layer called the lamina propria.At the trigone, the epithelium is more densely adherent to the underlying muscle.Deep to the transitional epithelium, the bladder submucosa with its microvasculature overlies the detrusor muscle.A layer of fatty connective tissue surrounds most of the anterior and lateral bladder in the retropubic space.

Urethra (Male)The male urethra is a fibromuscular tube. The prostatic urethra is lined with transitional cell epithelium (urothelium).The membranous urethra is lined with stratified columnar and pseudostratified epithelium.A rich vascular submucosa exists in the membranous urethra.The entire posterior urethra is lined with a submucosa and a series of muscular sphincters.Small diverticula, called lacunae of Morgagni, and a larger lacuna magna can be found at the fossa navicularis.

Urethra (Female)The female urethra is a multilayered tube lined by transitional cell epithelium proximally and by nonkeratinizing stratified squamous epithelium distally.The submucosa is surrounded by a longitudinal smooth muscle layer and then by a thicker circular smooth muscle layer (the involuntary internal urethral sphincter).Surrounding these layers in the middle and distal urethra is a striated muscle sphincter (the voluntary external urethral sphincter).

The innervation of the ren is coming from :Plexus coelicus Plexus aorticusThe lower part of nervous splanchnicus

UreterVascularization for ureter comes from the branch of :renalis arteriesSpermatica interna arteriesHypogastrica arteriesVesicalis inferior arteries

Ureters innervation is from autonomic system :Parasymphatic from nervous vagus and n. splanchnicusSymphatic from the T12-L2 segmentation

Vesica urinariaThe vascularization of it , are coming from :Vesicalis superior arteriesVesicalis caudalis arteriesObturatoria arteriesGlutea inferior arteries

The innervation of bladder:Symphatic : L1-L2 , and become plexus hypogastricusParasymphatic : n. splanchnicus , S2-3-4 segmentation

Congenital Disease

An ectopic kidney is a birth defect in which a kidney is located below, above, or on the opposite side of its usual position. About one in 900 people has an ectopic kidney.Ectopic KidneyAn ectopic kidney may remain in the pelvis, near the bladder.An ectopic kidney may cross over and become fused with the other kidney.Normal

Renal agenesis is the failure of kidney formation during fetal development. Renal agenesis can be unilateral, with one kidney present, or bilateral, with no kidneys or very little kidney present. The two types of renal agenesis have very different clinical courses, with unilateral agenesis being more favorable.Renal Agenesis

Duplex KidneyDuplex kidney is if two ureters draining urine into the bladder.

Horseshoe Kidney occurs during fetal development and it can be seen in one in 500 children. When the kidneys of fetus rise from the pelvic area and fuse together at the lower end, forming "U" shape. That is how Horse Kidney gets its name. This disorder is more common in male than female.Horseshoe Kidney (a) Normal position of the kidneys with divergent axes and medial exit of the ureters. (b) Horseshoe kidney in deep lumbar position with convergent axes and ventral exit of the ureters.

Nephroblastoma (Wilms' tumour)Wilms tumor is a cancer of the kidneys that usually affects children by 5 years of age but may also occur in the fetus. - Originates from the embryonal kidney- Pathologically contains renal tissue with various degrees of differentiation- Affects about 1 in 10,000 live births 60% present before the age of three years 10% tumours are bilateral The presentation is with an:oAbdominal mass (90%)oAbdominal pain (20%)oHaematuria (30%)

Separation of the primitive cloaca into the urogenital sinus and hindgut occurs during the first trimester at approximately the same time as maturation of the anterior abdominal wall. Failure of mesenchyme to migrate between the ectodermal and endodermal layers of the lower abdominal wall leads to instability of the cloacal membrane.Exstrophy-epispadiasOpen bladder plate and urethra with bifid clitoris in female patient with classic bladder exstrophy. Note low-set umbilicus and anteriorly displaced anusExternal view in female patient with epispadias.Labia are separated anteriorly.

Female patient with epispadias with labia retracted.The clitoris is bifid, and the urethra is open dorsally.

Penopubic epispadias in male patient.Typical spadelike configuration of glans penis with incomplete foreskin, dorsal urethral plate, and open bladder neck.

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