GINJAL

KUNCORO PUGUH S

FUNGSI

Pengaturan keseimbangan air & elektrolitPengaturan konsentrasi osmolaritas cairan tubuh & elektrolitPengaturan keseimbangan asam basaEkskresi hasil sisa metabolisme Pengaturan tekanan arteriSekresi hormonGlukoneogenesis

ExcretionThe removal of organic waste products from body fluids

EliminationThe discharge of waste products into the environment

Homeostatic regulation of blood plasmaRegulating blood volume and pressureRegulating plasma ion concentrationsStabilizing blood pHConserving nutrients

Functions of the urinary system

ANATOMI FISIOLOGI GINJAL ANJING

ANATOMI FISIOLOGI GINJAL SAPI

Figure 26.3

Figure 26.3 The Urinary System in Gross Dissection

ANATOMI & FISOLOGI

Cortical nephrons~85% of all nephrons

Located in the cortex

Juxtamedullary nephronsCloser to renal medulla

Loops of Henle extend deep into renal pyramids

Two types of nephron

Figure 26.7a

Figure 26.7 Cortical and Juxtamedullary Nephrons

Figure 26.7b, c

Figure 26.7 Cortical and Juxtamedullary Nephrons

Production of filtrate

Reabsorption of organic nutrients

Reabsorption of water and ions

Secretion of waste products into tubular fluid

Nephron functions include:

Regulating blood volume and composition

Excreting waste productsUrea

Creatinine

Uric acid

Urine production maintains homeostasis

FiltrationBlood pressure

Water and solutes across glomerular capillaries

ReabsorptionThe removal of water and solutes from the filtrate

SecretionTransport of solutes from the peritubular fluid into the tubular fluid

Basic processes of urine formation

Figure 26.9 An Overview of Urine Formation

Figure 26.9

Filtration in the kidneys modified by carrier mediated transport

Facilitated diffusion

Active transport

Cotransport

Countertransport

Carrier proteins have a transport maximum (Tm)

Determines renal threshold

Carrier Mediated Transport

Accomplished via diffusion, osmosis, and carrier-mediated transport

Tm determines renal threshold for reabsorption of substances in tubular fluid

Reabsorption and secretion

Superficial outer cortex and inner medullaThe medulla consists of 6-18 renal pyramids

The cortex is composed of roughly 1.25 million nephrons

Major and minor calyces along with the pelvis drain urine to the ureters

Sectional anatomy of the kidneys

NEPHRON

Merupakan unit fungsionil terkecil ginjal

1 Juta / Ginjal

Panjang seluruh nephron = 45 – 65 mm

GLOMERULUS

Kapsula Bowman : pars visceralis & pars parietalisFilter glomerulus : 3 lapis

1. Endhotelium kapiler :100nm2. Lamina basalis :8 nm3. Epithel Pars viceralis kapsula Bowman

( Podocyt) : 25 nmLuas area filtrasi 0,8 m2

Ultra filtrat = plasma - protein

Figure 26.10 Glomerular Filtration

Figure 26.10

Figure 26.8 The Renal Corpuscle

Figure 26.8a, b

Figure 26.8 The Renal Corpuscle

Figure 26.8c, d

Figure 26.10 Glomerular Filtration

Figure 26.10a, b

Proximal convoluted tubule (PCT)Actively reabsorbs nutrients, plasma proteins and ions from filtrate

Released into peritubular fluid

Loop of HenleDescending limb

Ascending limb

Each limb has a thick and thin section

Functional anatomy of the nephron

Animation: Urinary System AnatomyPLAY

Glomerular filtration produces fluid similar to plasma without proteins

The PCT reabsorbs 60-70% of the filtrate produced

Reabsorption of most organic nutrients

Active and passive reabsorption of sodium and other ions

Reabsorption of water

Secretion also occurs in the PCT

Reabsorption and secretion at the PCT

Animation: Early Filtrate ProcessingPLAY

Animation: Glomerular filtrationPLAY

TUBULUS PROKSIMALIS

P = 15 mmTight junctionLateral intercellular spaceBrush borderReabsorbsi 65 %Zat yg direabsorbsi tidak disekresi kecuali K+

Sekresi zat diikat oleh protein plasma

Figure 26.12 Transport Activities at the PCT

Animation: Proximal Convoluted TubulePLAY

Figure 26.12

The loop of Henle and countercurrent multiplication

Countercurrent multiplication Between ascending and descending limbs of loop

Creates osmotic gradient in medulla

Facilitates reabsorption of water and solutes before the DCT

Permits passive reabsorption of water from tubular fluid

ANSA HENLE

Pars decendent : 2- 14 mmPars Ascendent : mithokondria >>, Sel Junxtaglomerular vas. Afferent mensekresi RENINANSA HENLE SEGMEN TIPIS : permeabilitas besar, metabolisme minimalANSA HENLE SEGMEN TEBAL : tidak permeabel thd H2O & Ureum, reabsorbsi aktif Cl- & Na+

Figure 26.13a

Figure 26.13 Countercurrent Multiplication and Concentration of Urine

Figure 26.13b

Figure 26.13 Countercurrent Multiplication and Concentration of Urine

Figure 26.13c

Figure 26.13 Countercurrent Multiplication and Concentration of Urine

Distal convoluted tubule (DCT)Actively secretes ions, toxins, drugs

Reabsorbs sodium ions from tubular fluid

Functional anatomy of the nephron

Animation: Urinary System Dissection and FlythroughPLAY

DCT performs final adjustment of urineActive secretion or absorption

Absorption Tubular cells actively resorb Na+ and Cl-

In exchange for potassium or hydrogen ions (secreted)

Reassertion and secretion at the DCT

TUBULUS DISTALIS

P = 5 mm

Ephitel lebih pipih dari ephitel tubulus proksimalis

Brush border (─)

Bagian proksimal = segmen tebal ansa henle

Bagian distal terjadi ion exchange K+ dg Na+ : Hormon Aldosteron

Figure 26.14

Figure 26.14 Tubular Secretion and Solute Reabsorption at the DCT

Animation: Distal Convoluted TubulePLAY

Figure 26.14c

Figure 26.14 Tubular Secretion and Solute Reabsorption at the DCT

Reabsorption and secretion along the collecting system

Water and solute loss is regulated by aldosterone and ADH

ReabsorptionSodium ion, bicarbonate, and urea are resorbed

Secretion pH is controlled by secretion of hydrogen or bicarbonate ions

DUKTUS COLLIGENTES

P = 20 mm

Menampung beberapa tubulus distalis

Ber muara di papilla renalis

Bagian Cortex : tidak permeabel thd ureum

Bagian medulla ; permeabel thd ureum

ADH < : tidak permeabel thd H2O

Figure 26.6 A Representative Nephron

Figure 26.6

Figure 26.5 The Blood Supply to the Kidneys

Figure 26.5c, d

Figure 26.5 The Blood Supply to the Kidneys

Figure 26.5a, b

SUPLAI DARAH GINJAL

RENAL FRACTIONVasa afferent glomerulus membentuk vasa recta

Renal Blood Flow = 1200 ml/menit

Cardiac Out Put = 5000ml/ menit

Renal Fraction = 1200/5000 X 100% = 24%

KECEPATAN ALIRAN DARAH TIAP 100 g JARINGAN

ORGAN BLOOD FLOW (ml / min )

Otot Skelet

Otak

Hati

Otot Jantung

Ginjal

3

54

58

84

420

ALIRAN CAIRAN DLM TUBUH

JARINGAN Kecepatan (ml/min)

Reabsorpsi ( %)

Tubulus Proksimal

Ansa Henle

Tubulus Distalis

Duct. Colligentes

Urine

125

45

25

12

1

65

15

10

9,3

0,7

REABSORPSI ELEKTROLIT

( kation ) perlu dikendalikan, bila berubah : kegagalan faal ginjal

K+ > : potensial membran < : paralisis

K+ < : potensial membran > : paralisis

Na+ << : Potensial aksi < : paralisis

Ca++ < : permeabilitas membran > : tetani

Amount of filtrate produced in the kidneys each minute

Factors that alter filtration pressure change GFR

Glomerular filtration rate (GFR)

GLOMERULAR FILTRATION RATE ( GFR)

Jumlah filtrat yg disaring dr plasma dalam satu menit

Normal : 125 ml / min

Lebih dr 99% direabsorpsi

Produk urine : 1 L / hari

Zat yg digunakan untuk mengukur : Inulin, Manitol

A drop in filtration pressure stimulates Juxtaglomerular apparatus (JGA)

Releases renin and erythropoietin

Factors controlling the GFR

FAKTOR YG MEMPENGARUHI

Perubahan Tek. Darah

1. Tek. Darah umum

2. Status vasa afferent / efferent

Contoh :

latihan jasmani : vasokontriksi vasa afferent

Caffein : Vasodilatasi vasa afferent

Perubahan Tekanan Capsular : Obstruksi, Edema jaringan

Perubahan Tek. Osmotik Koloid : Dehidrasi, Hipoprotein

Perubahan Permeabilitas : Peny. Ginjal, Keracunan Obat

Perubahan Luas Area Filtrasi : Peny. Ginjal, Nephrotomy

FILTRASI GLOMELURUS

Effective Filtration Pressure (EFP)

Tek. Darah – Tek Capsular – Tek Koloid Osmotik = 70 – 20 – 32 = 18 mmHg

DIURETIKA

Zat yg dpt meningkatkan kec.pembentukan urineCara :

1. Meningkatkan GFR2. Mengurangi reabsorpsi cairan dlm tubuh

Terapi : Edema , HipertensiMekanisme kerja :

1. Meningkatkan GFR2. Meningkatkan muatan osmotik koloid tubuh3. Menghambat ADH

MENINGKATKAN GFR

Cara :

1. Tek darah >

2. Vasodilatasi vasa afferent

3. Vasokonstriksi vasa efferent

4. Tek. Osmotik Koloid <

BEBERAPA JENIS OBATEPINEPHRINE : Tek darah Tek Caps Bowman GFR Diuresis DIGITALIS : Decompensatio Cordis sirkulasi diperbaiki P Bowman GFR Diuresis THEOPHYLIN & CAFFEIN : Vasodilatasi Vasa Aff. P Bowman GFR Diuresis

MENINGKATKAN MUATAN OSMOTIK TUBULUS

1. Mempunyai efek terutama di tub. Proks: Ureum, Sukrosa, Manitol, Glukosa

2. Menghambat Reabsopsi Na+Di Ansa Henle : Furosemide, Ethacrynil AcidDi Tub. Distal bgn Proksimal : thiazide, metalazoneDi tub. Distalis bgn Distal : spironolactone, amiloride

Menghambat ADH

ADH reabsorpsi H2O di Ductus colligentes diuresisAlkohol, narkotika, anastesi

Figure 26.11a

Figure 26.11 The Response to a Reduction in the GFR

Figure 26.11b

Figure 26.11 The Response to a Reduction in the GFR

Figure 26.16 A Summary of Renal Function

Figure 26.16a

Figure 26.15

Figure 26.15 The Effects of ADH on the DCT and Collecting Ducts

Figure 26.15a, b

Figure 26.15 The Effects of ADH on the DCT and Collecting Ducts