SITEM URINARI

(1)

SISTEM URINARI

DISEDIAKAN OLEH:

SUHAIMI BIN SAHAT

(2)

(3)

FUNGSI SISTEM URINARI

(4)



Tubuh kita akan menghasilkan bahan kumuhan

yang mengandungi nitrogen iaitu urea dan uric acid



Ianya terhasil ketika sel-sel tubuh memecahkan

protein

proteins dan nucliec

s dan nucliec acids.

acids.



Sist

em urinari

berfungsi menghilangkan sisa

nitrogen dari tubuh, dan menetapkan air,

elektrolit, dan keseimbangan

acid-base

_{darah dan}

merembeskannya dalam bentuk urine.



Sistem ini, sering disebut

Sistem ini, sering disebut sistem ekskret

sistem ekskretori (

ori (

system

excretory

), yang terdiri daripada ginjal, ureter,

urinary bladder

(5)

GINJAL GINJAL URETER URETER URETHRA URETHRA URINARY BLADDER URINARY BLADDER INFERIOR VENA INFERIOR VENA CAVA CAVA RENAL VEIN RENAL VEIN RENAL ARTERY RENAL ARTERY

(6)

(7)

(8)

FUNGSI GINJAL

Menapis darah

•

_{merembes bahan}

buangan

•

_{mempertahankan}

kadar air, garam

mineral, protein dan

nutrisi dalam tubuh

Fungsi endokrin

•

_{menetapkan tekanan}

darah

•

_{menghasilkan renin,}

eritropoietin &

prostaglandin

•

_{menukarkan vitamin D}

bentuk aktif

Menghasilkan urine

(9)

STRUKTUR GINJAL

Capsule Hilum

• ureter → renal pelvis → major and minor calyxes

• renal artery and vein → segmental arteries → interlobar arteries → arcuate arteries → interlobular arteries Medulla • renal pyramids • cortical/renal columns Cortex • renal corpuscles

• cortical labryinth of tubules • medullary rays

CAPSULE

MEDULLA

(10)

Renal Lobe

= renal pyramid & overlying cortex

Renal Lobule = medullary ray &

surrounding cortical labryinth

Cortex

Medulla

Papilla Calyx

(11)

Renal Cortex



Bahagian terluar ginjal- antara renal capsule dan renal

medulla



Membentuk zon luar terus menerus halus dengan sejumlah

unjuran (cortical columns) yang membentang di antara

piramid.



Ini mengandungi renal corpuscles dan renal tubules

-kecuali untuk sebahagian daripada loop of Henle yang

turun ke renal medulla.



Mengandungi vessels darah dan cortical collecting duct.



Merupakan sebahagian daripada ginjal di mana terjadi

ultrafiltrasi

(12)

Renal Medulla

Lapisan paling dalam pada ginjal.

Terbahagi kepada beberapa bahagian, yang dikenali sebagai renal pyramids.

Darah masuk ke dalam buah pinggang melalui renal artery, yang kemudian dibahagikan untuk membentuk arcuate arterioles.

Arcuate arterioles berubah menjadi arteriol interlobular, yang akhirnya mencapai glomeruli.

Pada glomerulus, darah mencapai kecerunan tekanan yang sangat tinggi dan kawasan pertukaran permukaan yang luas, yang memaksa bahagian serum darah keluar dari vessels ke dalam renal tubules..

Mengalir terus melalui tubul ginjal, termasuk tubul proksimal, Loop of Henle

Akhirnya meninggalkan buah pinggang melalui saluran mengumpul, mengarah ke renal ureter.

(13)

III. The Nephron

a) renal corpuscle (bahagian awal nephron)

i) 1 - 4 million pada setiap ginjal ii) Berlaku penapisan darah

iii) glomerulus:

(14)

-tuft of capillaries about 200 microns in diameter - capillaries are fenestrated without diaphragms - thick basal lamina produced by both endothelial cells of capillaries and podocytes that wrap

around capillaries

- 10 - 20 capillary loops

- blood enters glomerulus at the afferent

arteriole, passes through glomeruli capillaries then exits at the efferent arteriole

- both afferent and efferent arteriole are located at the vascular pole of the renal corpuscle

(15)

Nephron: Vascular System

•

Afferent arteriole

•

Glomerulus

•

Efferent arteriole

•

Peritubular

capillaries

–

Capillary beds

reabsorb in cortex

•

Vasa recta

–

Capillary beds

reabsorb in medulla

(16)

Nephron

•

Tubular system

–

Glomerular Capsule

–

Proximal convoluted tubule

–

Loop of Henle (nephron loop)

•

Descending limb

•

Ascending limb

–

Distal convoluted tubule

(17)

(18)

(19)

Jenis Nephrons

i) coritical

-biasanya pendek dilengkarkan nephrons

-Sel darah di korteks luar,

-loop Henle pendek

-U-turn terjadi pada atau dekat pada

ketebalan distal tubule lurus di dasar dari

piramid ginjal (berhampiran cortex/medulla

(20)

Renal piramid

Renal pyramids (or malpighian pyramids) adalah tisu ginjal yang berbentuk kon.

The renal medulla terdiri daripada 8 hingga 18 dari bahagian-bahagian kon.

Dasar yang luas dari setiap piramid wajah korteks ginjal, dan puncaknya, atau papilla, mata dalaman.

Piramid muncul bergaris kerana mereka dibentuk oleh segmen selari langsung dari nefron.

(21)

Renal Papila

Di ginjal, renal papilla berada di

mana piramid medullary urin kosong

ke renal pelvis. Histologi hal ini

ditandai dengan saluran mengumpul

meduler untuk menyalurkan

(22)

Calyx (ces)

The minor calyx, in the kidney, surrounds the apex of the

malpighian pyramids. Urine formed in the kidney passes through a papilla at the apex into the minor calyx then into the major calyx.

Peristalsis of the smooth muscle originating in pace-maker cells originating in the walls of the calyces propels urine through the pelvis and ureters to the bladder .

The major calyx, in the kidney, surrounds the apex of the malpighian pyramids. Urine formed in the kidney passes through a papilla at

the apex into a minor calyx then into major calyx before passing through the renal pelvis into the ureter .

(23)

Renal Pelvis

juxtamedullary

- typically long-looped nephrons

-corpuscle at the base of the renal pyramid (near the

cortex/medulla junction), long loops of Henle with the U-turn in the thin, straight, proximal tubule deep in the

medulla (near the tip of the renal pyramid)

intermediate

- in between the above 2 types

The renal pelvis is the funnel-like dilated proximal part of the ureter in the kidney.

It is the point of convergence of two or three major calyces. Each renal papilla is surrounded by a branch of the renal pelvis called a calyx.

(24)

Renal Corpuscle

Urinary / Bowman’s space Glomerulus Bowman’s capsule visceral layer parietal layer

(25)

Bowman’s capsule:

•double-walled epithelial capsule around glomerulus •inner (capillary) layer called visceral layer:

-cells include mesangial cells and podocytes

mesangial cells have phagocyte function and are found within the basal lamina and clean the basement membrane of debris

• podocytes have processes called pedicels that wrap around capillaries

and that are in direct contact with the basal lamina:

- pedicels arise from primary processes of podocytes

- pedicels processes are separated by 25 nm slits called filtration slits - this plus basal lamina and net negative charge of basal lamina limit permeability of capillary to < 70,000

- allows ions and small proteins to pass into urinary system, retains most plasma proteins in blood

(26)

Juxtaglomerular apparatus • macula densa pada distal tubule

• JG cells in afferent arteriole • extraglomerular mesangial cells

Glomerulus

• fenestrated capillaries • podocytes

(27)

outer layer called parietal layer:

-delimits corpuscle

- simple squamous epithelium with

tight junctions

space between inner and outer layer

called urinary space:

-blood ultra-filtrate resides here

-parietal layer fuses with proximal

convoluted tubule:

- location called urinary pole of

corpuscle

(28)

Podocytes

(29)

Proximal tubule

• proximal convoluted tubule

• thick descending limb Henle’s_loop

Henle’s_loop

• thin descending & ascending limbs

Distal tubule

• thick ascending limb Henle’s _loop

• distal convoluted tubule • macula densa in DCT Collecting tubule & duct

(30)

Proximal Convoluted Tubule

• Cuboidal (low to high) cells

• Eosinophilic granular cytoplasm • Basal nuclei

• Elaborate brush/striated border • Lateral interdigitations

• Resorbs 100% protein, amino acids, glucose, creatinine, and bicarbonate ions

• Resorbs 70-80% of Na+, Cl-, and water • Na+/K+ pumps in basolateral membrane • Na+ pumped into interstitium

• Cl- and water follow

(31)

Henle’s Loop (thin segments)

• Squamous cells

• slightly thicker than endothelial cells • Few short microvilli

• Lateral interdigitations

• Descending limb

• highly permeable to water, salt and

urea

• Ascending limb

• impermeable to water

• permeable to salt which enters

(32)

Distal Tubule

(DCT & thick ascending limb of Henle’s loop)

• Low cuboidal cells • Clear pale cytoplasm • Apical nuclei (DCT)

• Central nuclei (Henle’s loop) • Numerous mitochondria

• Absent (or few short) microvilli • Basal interdigitations

• Numerous zonula occludens • Not permeable to water or urea

• Active Na+/K+ pumps (DCT)

• aldosterone stimulates salt resorption • H+ and K+ transported into lumen

• Active Cl- pumps (Henle’s thick) • Cl- enters interstitium (Na+ follows)

(33)

collecting tubules and ducts

i) the convoluted distal tubule connects to a collecting tubule (normal or arched) in the cortical labyrinth in the cortex

ii) the collecting tubule continues towards the medullary ray and connects to straight collecting tubules

iii) straight collecting tubules merge in the medullary ray (thus

straight) within the cortex forming the cortical collecting ducts

iv) cortical collecting ducts merge and progress towards medullary pyramid forming the papillary ducts of Bellini

v) papillary ducts of Bellini empty final urine (old fart urine) into the minor calyx at the tip of the renal pyramid (papilla) at the area cribrosa

(34)

(35)

vi) epithelia of collecting tubules and ducts:

-collecting tubule/duct lumen lined by simple cuboidal epithelia -central nucleus

-poor staining cytoplasm

-no lateral or basal interdigitations -cell margins very obvious

- have a single cilium and sparse, short microvilli on the apex (lumenal side)

- as the duct progresses towards the area cribrosa, the epithelia becomes taller and stratified

(36)

juxtaglomerular apparatus (jga)

i) adjacent to the renal corpuscle

ii) located at the vascular pole of Bowman’s capsule

iii) includes the macula densa of convoluted, distal tubule, juxtaglomerular cells of the afferent arteriole, and extraglomerular mesangial cells which are all in

close proximity at the jga

iv) smooth muscle cells of afferent arteriole have secretory granules containing renin and are called juxtaglomerular cells

- renin secretion from these smooth muscle cells is stimulated by paracrine activity from the macula densa of the convoluted, distal tubule

- renin is a protease that cleaves plasma angiotensinogen into angiotensin I - angiotensin I converted to angiotensin II in the lung

- angiotensin II promotes vascular smooth muscle contraction and release of aldosterone from the adrenal cortex

- aldosterone stimulates absorption of NaCl and water in the distal convoluted tubule thus increasing blood volume

(37)

Macula densa in distal tubule

•• monitor Na+ content and volume in DT •• low Na+:

•• stimulates JG cells to secrete renin

•• stimulates JG cells to dilate afferent arteriole •• tall, narrow columnar cells

•• numerous microvilli

JG cells

•• secrete renin into circulation

•• renin converts angiotensinogen → angiotensin I •• contain angiotensin converting enzyme (ACE) •• lung is principal site of ACE activity

•• ACE converts angiotensin I → II •• contain angiotensin I & II

•• angiotensin II constricts vasculature and stimulates •secretion of aldosterone and ADH

•• primarily in afferent arteriole •• specialized smooth muscle cells

•• no basal lamina between JG cells & macula densa

Extraglomerular mesangial cells

•• also known as Polkissen or lacis cells

Mesangial cell

JG cell Macula

(38)

Ureter ialah tiub yang keluar dari tiap-tiap buah pinggang.

Membawa air kencing ke dalam pundi-pundi kencing.

Salur ini dibahagiakan kepada dua bahagian:

- corong atau pelvis buah pinggang. Ini ialah

bahagian atas yang kembang. Ia bermula sebagai alat berbentuk mangkuk, yang dikenali sebagai kaliks.

-Salur buah pinggang benar. Ukurannya sepuluh inci panjangnya. Bahagian atasnya terletak di hadapan otot belakang abdomen, bahagian

bawah masuk ke dalam ruang pelvis dan berakhir di permukaan belakang pundi-pundi kencing.

-Tiap-tiap salur buah pinggang terbina daripada tisu berfiber,tisu otot bebas,tisu epitelium

(39)

• Pundi kencing merupakan organ penakung air kencing dan ianya terletak di dalam ruang pelvis benar.

• Bagi lelaki ,usus hujung terletak di belakangnya dan sendi ari-ari terdapat di hadapannya.

• Bagi wanita sendi ari-ari terdapat di hadapannya,tetapi rahim dan liang faraj terletak di belakangnya.

• Ruang di dalam pundi-pundi kencing menunjukkan satu bahagian segitiga yang dipanggil trigone

• Dasar segitiga berarah ke atas dan puncak ke bawah.

• Kedua-dua salur buah pinggang membuka di bahagian atau trigone manakala salur kencing bermula dari puncaknya.