L18- liver anatomy and homeostais and L19- paracetamol

Question 1

liver stores

Answer 1

glycogen , ADEK vits , iron and blood

Question 2

immune function of liver

Answer 2

phagocytosis of bacteria

Question 3

liver detoxification

Answer 3

first pass metabolism of drugs poisons and metabolic products

Question 4

4 liver lobes

Answer 4

right, left, quadrate and caudate

Question 5

connective tissue capsule surrounding liver

Answer 5

glissons capsule

Question 6

structural unit of liver

Answer 6

lobules

Question 7

single hepatocyte

Answer 7

epithelial cells withh one or 2 nuclei and 5-10 surfaces , 2 basal with microvilli and apical surface around middle of cell where bile is excretes, lateral surface connects neighbouring hepatocytes

Question 8

arrangement of hepatocytes

Answer 8

arranged into cords separated by sinusoids

Question 9

why is livrr prime site for metastatic spread of cancer

Answer 9

rich blood supple (1500ml per min)

Question 10

hepatic veins

Answer 10

taked processed blood to vena cava

Question 11

blood supply to hepatocytes

Answer 11

venous blood from hepatic portal vein
arterial blood from hepatic artery
mixes in sinusoids and drains into central vein

Question 12

sinusoid

Answer 12

small blood vessel found in liver- has similar function to capillary , have increased permeability compared to capillaries and allow larger molecules to leave the bloodstream

Question 13

endothelial sinusoid layer

Answer 13

contains large intercelluylar gaps to alow passage of larger molecules. Further leakage allowed by holes which penetrate endothelial cells.i

Question 14

sinusoid vs capillary

Answer 14

basement membrane is absent or discontinuous in sinusoids but continuous in capillaries

Question 15

space of disse

Answer 15

space between endothelium and hepatocytes, fluid from space of disse can drain into lymph nodes

Question 16

Kupffer cells found in

Answer 16

macrophage lineage in sinusoid

Question 17

kupffer cells are important for

Answer 17

removing particulate bacteria prom portal blood

Question 18

kupffer cells contain

Answer 18

red cell fragments and ferritin

Question 19

ito cells found in

Answer 19

space of disse

Question 20

importance of ito cells

Answer 20

hepatic fat and vitamin A, where its transportef drom liver to retina to form rhodopsin

Question 21

what happens if liver is continuously exposed to injury

Answer 21

ito cells become myofriboblasts and produce collagen, leading to fibrosis

Question 22

dendritic cells important for

Answer 22

liver immunity, autoimmunity and regulation of hepatic allograft acceptance

Question 23

dendritic cells are ____ presenting cells

Answer 23

antigen, which capture process and present antigen to immune effector cells

Question 24

biliary system is a

Answer 24

series of channels and ducts that conveys bile from the liver into the small intestine

Question 25

hepatocytes basal surface faces

Answer 25

the sinusoid

Question 26

hepatocytes apical faces of adjoining cells are held together to form

Answer 26

canaliculi

Question 27

bile secretion pathway

Answer 27

hepatocyte- bile canaliculi- canal of hering- interlobar bile duct- bile duct.

Question 28

portal triad consists of

Answer 28

hepatic artery, portal vein, bile duct

Question 29

bile flow and blood flow

Answer 29

flow in opposite directions

Question 30

bile leaves liver via

Answer 30

common hepatic duct

Question 31

sinusoid definition

Answer 31

low pressure vascular channels that recieve blood from hepatic artery and portal. They are lined with endothelial cells and surrounded by hepatocytes

Question 32

smallest functional unit of the liver

Answer 32

liver acinus

Question 33

zone 1 location

Answer 33

closest to short axis , then 2 and 3 get closer to central vein

Question 34

zone 1

Answer 34

periportal zone , first to recieve oxygen nutrients and toxins, and shop morphologic changes after bile duct occlusion, last cells to die if circulation is impared and first to regenerate oxidative metabolism, gluconeogenesis, urea genesis, bile formation

Question 35

zone 2

Answer 35

intermediate zone- functional and morphologcal characteristics and responses that are intermediate

Question 36

zone 3

Answer 36

most sensitive to hypoxia, first to show ischaemic necrosis, first to show fat accumulation, last to respond to toxic substances glycogen synthesis, glycolysis, xenobiotic metabolism

Question 37

kupffer cells are constantly exposed to

Answer 37

gut-derived bacteria, microbial debris and bacterial endotoxins

Question 38

upon activation KC release

Answer 38

cytokines, prostanoides, nitric ocide

Question 39

KC involved in

Answer 39

response to infection, toxins, ischemia, production of cytokines,chemokines, nitrogen and oxygen species

Question 40

M1 KC

Answer 40

pro inflammatory - increaseed expression of pro inflammatory cytokines

Question 41

M2 KC

Answer 41

resolution and wound healing - low expression of pro inflammatory cytokines, increased expression of anti- inflammatory mediators

Question 42

loss of tolerance of KCs leads to

Answer 42

hepatocute injury and damage

Question 43

KC protect against

Answer 43

drug induced liver injury and toxin induced fibrosis

Question 44

disregulation of inflammatory response in KC

Answer 44

chronic inflammation in the liver

Question 45

removal of KCs

Answer 45

prevents development of fatty liver and inflammation

Question 46

production of bile

Answer 46

hepatocytes secrete bile into canaliculi where it flows into bile dicts, hepatic bile contains large quantities of bile acids, cholesterol and other organic molecules

Question 47

how is bile modified

Answer 47

addition of watery bicarbonate rich secretion from epithelial cells

Question 48

how is nile produced

Answer 48

bile salts and phospholipids convert flat globules into smaller pieces with polar surfaces which inhibit reaggregation, emulsified fat globule are then small enough that lipase can break down tricglycerides to monoglycerides and fatty acids so then they can diffuse into epithelial xells of intestine or form micelles

Question 49

how much bile acid is secreted back into the duodenum

Answer 49

95%

Question 50

venous blood from ileum goes

Answer 50

to portal vein ,, so then through liver sinusoids

Question 51

what extracts bile acids from sinusoid blood

Answer 51

hepatocytes, where they transport across to be re-secreted into canaliculi

Question 52

how many times are bile salts reused

Answer 52

20

Question 53

how does liver help regulate coagulation and fibrinolysis

Answer 53

clearing coagulation factors from circulation

Question 54

what is vitamin K needes for

Answer 54

achieve proper levels of pro-coagulant factors and anticoagulant factors

Question 55

albumin plasma half life

Answer 55

20 days

Question 56

what stimulates albumin secretion

Answer 56

drop in plasma oncotic pressure

Question 57

albumin importance

Answer 57

acts as transport protein for fatty acids, ions and bilirubin

Question 58

albumin secreted in

Answer 58

hepatocytes of tthe liver - excreted in high quantities- minimal amounts are stored in liver

Question 59

what cyp is induced by ethanol

Answer 59

2E1

Question 60

conversion of paracetamol to NAPQI by

Answer 60

cyp2E1 cyp1A2 cyp3A4

Question 61

what increases risk of toxicity of paracetamol

Answer 61

increased napqui formation incution of cy2e1 and 3a4 chronic ethanol intake (2e1) enzyme inducers increased INR, GGT

Question 62

enzyme inducers

Answer 62

carbamazepine, phenobarbital, phenytoin, rifampicin, rifabutin, st johms wort

Question 63

when can activated charcoal be used

Answer 63

<2 hr after digestion or <4hr after massive overdose

Question 64

measure paracetamol conc after

Answer 64

4-16 hr after digestion (<4hr absorption incomplete)

Question 65

if paracetamol level is on or above treatment line

Answer 65

give N-acetylcysteine by IV

Question 66

what to monitor after overdose

Answer 66

lfts, cross match blood, serum glucose, renal function