Exam 3 Histo 3

Front 1

Macroscopic features of the kidney

Back 1

Cortex, Medulla, Calyces (major and minor), Hilum

Front 2

Feats of the Cortex

Back 2

Medullary arrays
Renal Column

Front 3

Medulla feats

Back 3

Renal pyramid (Renal papillae)

Front 4

Hilum feats

Back 4

Renal a.
Renal v
Renal Pelvis

Front 5

Kidney as an endocrine organ

Back 5

-Blood pressure regulation by the production of renin and the renin-angiotensin-aldosterone system.
-Maintenance of the oxygen-carrying capacity of the blood by the production of erythropoietin, which stimulates erythrocyte production in the bone marrow.
-Regulation of calcium balance by conversion of vitamin D to its active form

Front 6

Renal Cortex signature feat

Back 6

Renal corpuscle

Front 7

Renal corpuscle job

Back 7

filtration of blood

Front 8

Renal corpuscle consists of

Back 8

Renal glomerulus
Bowman's capsule
Vascular pole
Urinary pole

Front 9

Bowman's capsule consists of

Back 9

-Outer capsular epithelium (parietal wall) SIMPLE SQUAMOUS

-Urinary space

-Inner podocyte layer (visceral wall)

Front 10

Glomerulus

Back 10

Capillary loops with fenestrated endothelium and no diaphragm

Supported by Mesangial cells

Front 11

Capillaries that comprise the glomerulus are enclosed in

Back 11

inner podocyte layer (visceral layer) of bowman's capsule

Front 12

Pressure for the filtration process in the glomerulus is created by

Back 12

efferent and afferent arterioles to the glomerulus.

Efferent is smaller than afferent arteriole

Front 13

Glomerular filtration barrier from lumen of capillary out

Back 13

-Fenestrated endothelium of glomerulus
-Podocyte layer of Bowmans capsule
-Glomerular Basement Membrane:Basement membrane of podocyte and endothelial cells

Front 14

Feats of Glomerular Basement Membrane

Back 14

-Thick
-negatively charged
-Size selective
-Charge selective
-Main component of glomerular barrier

Front 15

Mesangial cells

Back 15

Remove trapped residues and aggregated proteins from the GBM-keeping the glomerular filter clean

Structural support(help regulating glomerular flow)

Contractile

Front 16

In case of glomerular injury, mesangial cells

Back 16

synthesize and secrete IL-1 and PDGF

Front 17

Juxtaglomerular Apparatus is important for

Back 17

control of systemic blood pressure and volume

Front 18

Where is the juxtaglomerular apparatus?

Back 18

At the vascular pole of the renal corpuscle

Front 19

Juxtaglomerular apparatus consists of

Back 19

Macula Densa
Juxtaglomerular cells
Extraglomerular mesangial cells

Front 20

Macula densa is

Back 20

specialized region of the distal convoluted tubule at the vascular pole

Front 21

Feats of the macula densa cells

Back 21

-Narrower and taller than other distal tubule cells
-Monitor Na+ concentration in tubular fluid
-Regulate the glomerular filtration rate and the release of Renin by Juxtaglomerular cells

Front 22

Juxtaglomerular cells feat

Back 22

located in the walls of the afferent arteriole

modified smooth muscle

Front 23

Juxtaglomerular cells secrete

Back 23

renin

Front 24

Goormaghtigh cells

Back 24

aka extraglomerular mesangial cells

support structure of the juxtaglomerular apparatus

Front 25

Proximal tubule feats

Back 25

-simple cuboidal
-microvilli on apical surface (reabsorption)
-irregular lumen
-indistinct lateral margins of cells

Front 26

Distal tubule feats

Back 26

-Simple cuboidal
-no microvilli
-lots of mitochondria
-round lumen
-lateral margins of cells are indistincts

Front 27

Thin segments of loops of henle feats

Back 27

-Simple squamous epithelium
-diameter similar to that of a capillar--capillary w/o blood cell

Front 28

Collecting tubule feats

Back 28

-simple cuboildal
-cell margins are distinct

Front 29

Collecting tubule cells

Back 29

Principal cells
intercalated cells (dark cells)

Front 30

Principal cells feats

Back 30

-single cillium
-defined cell margins
-centrally located nuclei

Front 31

In response to aldosterone, principal cells

Back 31

reabsorb Na+ and secrete K+

Front 32

In response to ADH principal cells

Back 32

reabsorb H2O

Front 33

Intercalated cells (dark cells) feats

Back 33

surface covered by microplicae and microvilli

lots of mitochondria

apically located nuclei

Front 34

Intercalated cells occur in

Back 34

small numbers (cortical collecting tubules, outer medullary collecting tubules)

Front 35

Alpha intercalated cells secrete

Back 35

H+

Front 36

Beta intercalated cells secrete

Back 36

bicarbonate

Front 37

Medullary ray located in

Back 37

renal cortex.

Straight tubules of the nephron and collecting tubules/ducts

Front 38

Renal tubule modifies ultrafiltrate by

Back 38

Active Absorption
Passive Absorption
Secretion

Front 39

Convoluted tubule function

Back 39

Absorption of Na, Cl, H20, Bicarbonate, AA, glucose

Front 40

Loop of Henle's job

Back 40

establishment of a gradient of solute concentration in the interstitial space

Front 41

Thin descending segment

Back 41

permeable to H20

Front 42

Thin ascending segment

Back 42

Permeable to NaCl (out)

Front 43

Thick ascending segment

Back 43

Active transport NaCl out from the tubule

Production of hyperosmotic urine

Front 44

convoluted tubule functions

Back 44

-secretes ammonium and some drugs
-reabsorbs sodium by active transport in response to aldosterone

Front 45

In response to ADH, distal tubule

Back 45

absorbs H20

Front 46

In response to ADH collecting duct

Back 46

concentrates urine by increasing their permeability to H20

Front 47

Collecting duct secretes and reabsorbs

Back 47

-H+, ammonium, drugs

-bicarbonate

Front 48

collecting duct is permeable to

Back 48

urea out of the ducts

Front 49

Peritubular cells in cortex of the kidney

Back 49

produce erythropoietin, which stimulates erythrocyte production in the bone marrow

Front 50

VitD conversion (for Ca2+ absorption) activated by

Back 50

cells of proximal tubules

Front 51

Transitional epithelium (urothelium) lines

Back 51

calyces, ureters, bladder, initial segment of the urethra

Front 52

Prostatic urethra feat

Back 52

= transitional

Front 53

Membranous urethra

Back 53

stratified or pseudostratified columnar

Front 54

Spongy urethra

Back 54

pseudostratified columnar to stratified squamous at the distal end

Front 55

Female urethra

Back 55

Initially transitional changing to stratified squamous

Front 56

Hepatocytes have 3 surfaces

Back 56

Basal
Apical
Lateral

Front 57

Basal surface of hepatocyte function

Back 57

absorptive: faces the space of disse where the exchange takes place

Front 58

Apical surface of hepatocyte function

Back 58

Secretory.; bile canaliculus

Front 59

Lateral

Back 59

Adhesive or communicative at junction with neighboring cells

Front 60

Sinusoidal Endothelial cells in the hepatocyte are

Back 60

fenestrated, no diaphragms, large gaps between cells. Slow flow and large gaps allow passage of proteins but not cells adjoining to the space of disse

Front 61

Basal lamina of sinusoidal endothelial cells is

Back 61

discontinuous

Front 62

Blood flow in sinusoidal endothelial cells is slow because

Back 62

sinusoidal channels are wide and uneven and the flow carries Kupffer cells

Front 63

Perisinusoidal cells in the hepatocytes are aka

Back 63

fat-storing cells of Ito, hepatic stellate cells, lipocytes, in the Space of Disse
Derived from mesenchyme

Front 64

Perisinusoidal cells are the primary storage of

Back 64

Vit A and produce ECM components

Front 65

Perisinusoidal cells job is to

Back 65

regulate sinusoidal blood flow and their cytoplasm has desmins

Front 66

Perisinusoidal cells respond to

Back 66

Kupffer cell cytokines

Front 67

The fixed part of the sinusoidal lining is

Back 67

kupffer cells but they do not form junctions but they may span lumen and partially occlude it

Front 68

Kupffer cells may contain fragments of

Back 68

RBC and ferritin

Front 69

Space of Disse

Back 69

Region between basal surface of the hepatocyte & basal surface of sinusoidal cells

Front 70

Stellate Ito cells are believed to reside in

Back 70

Space of disse, and these cells give support to the channel

Front 71

What protudes into the space of disse?

Back 71

Hepatocyte microvilli protrude into the space for absorption and exchange with blood

Front 72

Hepatocyte products other than bile are transferred to

Back 72

the perisinusoidal space; lymph flows in this space

Front 73

In the fetus, blood forming cells are found in

Back 73

space of disse...in anemic adults they may be found here too

Front 74

In the hepatic lobule, plates of hepatocytes are separated by

Back 74

by sinusoids,
surrounding a central
Vein* with portal areas
at the periphery.

Front 75

Zone 1 - Periportal of liver acinus

Back 75

Outer boundary is “Limiting Plate” of cells
Closest to vascular supply of nutrients & O2
Minimal exposure to metabolic waste products
Cells in this zone very active in synthesis of glycogen and plasma proteins

Front 76

Zone III - Centrilobular of liver acinus

Back 76

Vascular supply almost depleted of nutrients & O2; metabolites more concentrated here
Main site of alcohol & drug detoxification
First zone to be affected in malnutrition
Susceptible to cytotoxic damage from toxic metabolites produced during detoxification reactions

Front 77

Response to Hepatic Injury ensues in the following steps

Back 77

-Degeneration and intracellular accumulation
-necrosis and apoptosis
-inflammation
-regeneration
fibrosis

Front 78

Regeneration involves

Back 78

hepatocytes have long life span ~5mos, proliferate in response to tissue resection or cell death

Front 79

Fibrosis

Back 79

formed in response to inflammation or toxic insult; other responses reversible, fibrosis points toward irreversible hepatic damage

Front 80

Ito cell activation (which sits on the space of disse) leads to

Back 80

release of tumor necrosis factor which induces conversion of ito cell to myofibroblast cell

Front 81

Myofibroblast job

Back 81

they proliferate and fill up the space of disse by producing ECM components which block cannal. They also contract and fibrosis ensues in the space of disse

Front 82

Centrilobular necrosis characteristics

Back 82

due to Congestive heart failure leads to Oxygen depletion in zone 3 as well as fat accumulation

Front 83

Mallory body formation due to

Back 83

alcohol cirrhosis, aggregates of keratin can be seen

Front 84

portal lobule is defined by

Back 84

bile flow

Front 85

Production of bilirubin steps

Back 85

1-Senescent RBCs are broken
down in the spleen, liver, or
marrow; hemoglobin is broken
down into heme + the
component aa’s of globin which
return to the pool; heme is
oxygenated to biliverdin which is
reduced to bilirubin
2-Bilirubin is bound to albumin
and transported to the liver
3-Bilirubin is transported across the
hepatocyte membrane by
receptor-mediated endocytosis
4-is conjugated to glucuronic acid
forming bilirubin glucuronide.
Bilirubin glucuronide is released
in the bile at the apical surface
into the bile canaliculus and then
into the bile duct system.

Front 86

Elimination or bilirubin

Back 86

In the distal part of the small intestine, bacteria degrade bilirubin glucuronide; most of the urobilinogen and pigment which are formed is excreted in the feces. About 20% of the
urobilinogen is reabsorbed in the ileum and colon.

Front 87

Disruption of the pathway at the steps of bilirubin absorption or conjugation to glucuronide or secretion of glucuronide can lead to

Back 87

Jaundice

Front 88

Leading out of intrahepatic ductule can see the

Back 88

herrying cannal, stem cells are located here

Front 89

Wall of herrying body is made up of

Back 89

collangiosides and hepatocytes

Front 90

Lymphatics in the lobule do not

Back 90

travel in the bile canniculi but do travel in the direction of bile

Front 91

As bile canniliculi go out to exterior of liver they increase in size and when they get to the portal section they are known as

Back 91

space of mall

Front 92

Gallbladder concentrates and stores bile

Back 92

electrolytes are moved to the intercellular space by active transport, water from the lumen and cytoplasm follows the gradient concentrating the dilute bile

Front 93

gallbladder contraction in response to

Back 93

cholecystokinin from the intestinal enteroendocrine cells releases bile into the duodenum

Front 94

Gallbladder feats

Back 94

Lacks both a submucosa and muscularis mucosae.
Has a serosa or adventitia

Front 95

in the muscularis externa of the gallbladder it may precede pathologic changes; can accumulate bacteria causing inflammation

Back 95

Rokitansky-Aschoff sinuses (diverticula from the mucosa),

Front 96

Cholestasis

Back 96

dysfunction in bile formation or secretion by the hepatocyte or an obstruction preventing excretion in the extrahepatic biliary tract

Front 97

Cholelithiasis

Back 97

- gallstones formed from cholesterol, salts, etc.; can cause cholestasis

Front 98

Functions of Bile

Back 98

Excretion of cholesterol, phopholipids, bile salts, conjugated bilirubin and electrolytes

Excretion of the metabolic products of hepatic processing, e.g., drug metabolites, heavy metals

Conjugated salts of the bile acids are very effective detergents which solubilize lipids secreted from the liver into bile and dietary lipids in the small intestine

Front 99

Classic lobule of the liver

Back 99

visually separate into tessellated hexagonal units

Front 100

Portal lobule of the liver

Back 100

Triangular units with bile canaliculi converging into a bile ductule

Front 101

Liver acinus feats

Back 101

Rhombus/ellipse-shaped units, blood perfuse from the short axis to the central vein