Liver and Pancreas Flashcards
(117 cards)
1
Q
what are the major fuctions of the liver?
A
- Detoxification of metabolic waste
- Metabolism & detoxification of drugs & toxins
- Destruction of senescent RBC’s
- Recycling of Hb via synthesis & secretion of bile
- Synthesis of plasma proteins
- Miscellaneous metabolic functions
2
Q
The liver demaiton of
A
Amino Acids to urea
3
Q
Products of digestion enter the liver via
A
hepatic portal vein
4
Q
the hepatic portal vein caries
A
- 75-80% of blood to the liver
- oxic compounds absorbed from diet
5
Q
Oxygentated blood supplied to the live by
A
Hepatic Artery
6
Q
The hepatic artery is a branch of the
A
celiac trunk
7
Q
The hepatic artery carries only
A
20%-25 blood of the liver
mixes with unoxygenated from potal vein
8
Q
Liver is a nutrient rich, but is
A
O2 poor environment
9
Q
What is the order of venous drainage?
out of the liver
A
central vein –> hepatic vein
–> IVC
10
Q
What is the main funcitonal cell of the liver
A
Hepatocytes
11
Q
Hepatocytes are arranged in
A
plates or cords
around sinusoids
12
Q
In the liver Endothelial cells line the
A
sinusoids
13
Q
What ar the liver specific macrophages?
A
Kupffer cells
14
Q
What cells store vitamin A & D in the liver
A
Stellate cells (Ito cells)
major for A
15
Q
What are liver cells called
A
hepatocytes
16
Q
hepatocytes shape
A
- polyhedral
- round nucleus
displaced chromatin - prominent nucleolus
17
Q
Most hepatocytes _______,
but some are _____
A
diploid; polyploid &/or
binucleate
18
Q
What are within the cytoplasmic granules of hepatocytes
A
rER
& lysosomal products
19
Q
What do Aging hepatocytes
accumulate?
A
brown
pigment, lipofuscin
20
Q
individual hepatocytes polygonal, arranged in
anastomosing cords paralleled by
A
Venous Sinusoids
21
Q
Sinusoids lined by
A
sinusoidal
lining cells
22
Q
sinusoidal lining cells
A
a discontinuous
endothelium, with gaps
between endothelial cells
23
Q
What supports the hepatic cords and sinusoids?
A
meshwork of
reticulin fibers (Type III
collagen)
24
Q
The reticulin fibers that support the Hepatic cords & sinusoids are what type of collagen?
A
type 3
25
What blackens the cytoplasm of kupffer cells?
carbon particles
26
Kupffer cells can be recognized by
their oval
nuclei closely associated
with sinusoidal spaces.
27
What can be used to stain Kupffer cells
trypan blue
28
Kupffer cells removve
* foreign particles
| they also work with the spleen to destroy old RBCs
29
What are other names for the Stellate cells
* Ito cell
* perisinusoidal cell
* lipocyte
30
If the liver is injuried what happens
* stellate cells become transitional
* become capable of collagen synthesising
31
What types of collagen can Stellate cells synthesize?
1
| aslo 3 and 4 and laminin
32
Do blood and bile travel in the same direction?
NO
33
Hepatic SInusoids
* Thin
* discontinuous
* highly fenestrated
* endothelium
34
Do the hepatic sinusoids rest on a basement membrane?
NO
35
What seperates the hepatic sinusoids from the hepatocytes?
space of Disse or perisinusoidal space
36
Space of Disse
| perisinusoidal space
* found in the liver
* between hepatocytes and sinsuoid
* contain blood plasma
37
What portion of the hepatocyte extends into the Space of Disse
microvilli
38
Microvilli of hepatocytes
allowing proteins and other plasma components from the sinusoids to be absorbed by the hepatocytes.
39
What is a low resistance vascular channel
hepatic sinusoids
40
what makes bile?
hepatocytes
41
where do hepatocytes secrete bile into?
bile canaliculi between cells
42
Blood flow in the liver
Hepatic vien/artery-(in triad)>
hepatic sinusoids->
central vein (then out of liver)
43
bile flow in liver
hepatocypes make->
bile canal->
bile duct
| opposite if blood
44
Cords of hepatocytes are arranged in
lobules
45
Classic Lobule
*** based on blood flow**
* roughly hexagonal
* central vein in middle of lobule
46
what is at the center of the classic lobule?
centrilobular vein
47
What is the outer margin of each lobule?
connective
tissue septum
48
The central vein in middle of lobule can also be refered to as
* centrilobular vein
* terminal hepatic venule
49
Where do you find portal tracks?
| triads
each coner of the classic lobule
50
The portal tract/triad contain
hepatic artery, portal
Vein & bile duct
## Footnote
lymphatics too?
51
Blood enters from portal tracts,
percolates through sinusoids of lobule,
drains via
central vein
52
Portal Lobule is
* triangular area
*** based on bile flow**
53
In a portal lobule has a portal triad ______ and central vein ___________
center; at corners
54
liver Acinus
* diamond–shaped
* between neighboring central vein
55
What are the zones of the Acinus
zones 1, 2 , and 3
56
The acinus Combines aspects of
* blood flow
* oxygenation
* metabolism
* pathology
57
What is the name of zone 1 of Heptaic Acini
perilobular zone = periportal
58
Zone 1 of Hepatic Acini
closest to portal tract,
59
Which zone of Hepatic Acini receives the most oxygenated blood?
Zone 1
| perilobular zone = periportal
60
What zone of Hepatic Acini is most susecptible to toxic injury?
Zone 1
61
What it the name of zone 2 of Hepatic Acini
intermediate zone
62
What it the name of zone 3 of Hepatic Acini
centrolobular zone
63
Which Heptaic acini zone is furthest from the portal track
Zone 3
| centrolobular zone
64
Which Heptaic acini zone is closest to the cental vein?
Zone 3
| centrolobular zone
65
Which zone of Hepatic Acini recieves the least oxygentated blood?
zone 3
| centrolobular zone
66
Which zone of hepatic acini is most susceptible to ichemic injury?
Zone 3
| centrolobular zone
67
What helps the liver fucntion in detoxification/metabolism of various drugs and toxins
* microsomal mixed function
oxidase system of sER
* peroxidases of peroxisomes (P450 system)
68
P450 system is related to
peroxidases of
peroxisomes
69
Cirrhosis
A common sequela to repeated insults or chronic disease
70
Cirrhosis is Characterized by hepatic degeneration and
necrosis
71
What follow necrosis in liver cirrhosis
fibrosis & nodular regeneration
72
Portal hypertension is associated with
cirrhosis
73
Portal hypertension is due to
fibrosis,
blockage of blood flow
74
Liver has ability to
regenerate
75
Gallbladder is a muscular sac located
depression
along surface of liver
76
Gallbladder is used to store & concentrate
bile;
volume ~100 m
77
The gallbladder is lined by
simple columnar epithelium
with apical microvilli
78
The microvilli lining the gallbladder are used for
resorption of water
79
Gallbladder lacks a
muscularis mucosae
80
Lamina propria of the gallbladder is highly folded with occasional
tubuloalveolar mucus
glands
81
What does CCK (cholecystokinin) stimulate?
contraction of gallbladder
82
What are the conponents of bile?
* water
* ions
* electrolytes
* cholesterol
* phospholipids( lecithin)
* bile acids/salts/pigments
83
What is the best known bile pigment?
Bilirubin
84
Bilirubin
non-sol breakdown product of Hb
85
What happens if you are unable to o absorb bilirubin or failure to
conjugate it & secrete it?
accumulation of bile
pigments = jaundice
86
Supersaturation of bile can lead to
gallstones
(biliary calculi, cholelithiasis)
87
What are the primary kind of gallstones?
cholesterol & calcium salt
88
choledocolithiasis
Obstruction of bile duct
89
cholecystitis
Chronic inflammation of the gallbladder
90
cholecystectomy
removal of gallbladder
91
If someone gets their gallbladder removed they should
limit the amount of fats they eat
| due to being unable to concentrate bile
92
Pancreas has both
exocrine & endocrine
components
93
Where do you find the ductless endocrine
pancreatic tissue?
islets of Langerhan
94
Most of the pancreas is
exocrine (has ducts)
95
In the pancreas acinar cells contian
zymogen granules
96
zymogen granules
inactive enzyme
precursor
97
zymogen granules is a precursor to
* trypsinogen (protrypsin)
* chymotrypsinogen (prochymotrypsin)
* amylase
* lipase
98
Trypsin & chymotrypsin are
proteases
99
amylase breaks down
carbohydrates
100
lipases digest
lipids
101
intercalated ducts of the pancreas add
bicarbonate & water to pancreatic sections
102
intercalated ducts of the pancreas neutralize
acidic chyme from stomach (optimal pH for pancreatic enzymes)
103
Duct cells that form beginning of intercalated ductsometimes visible
in center of acini are called
centro-acinar cells
104
What do Intercalated ducts empty into?
larger intralobular ducts
105
intralobular ducts exit into
interlobular (=extralobular)
ducts
106
Where do pancreatic secretions enter the GI tract?
duodenum via pancreatic
duct at major duodenal
papilla
107
What cells secrete Gastrin?
G cells
| by stomach
108
Gastrin stimulates
secretion of pancreatic fluid
109
What 3 things does teh duodenum APUD cells secrete?
* secretin
* CCK
* enterokinase
110
What secretes CCK?
I cells
111
CCK stimulates
| pancreatic regulation
acinar
cells to secrete zymogens
112
Enterokinase converts _________ to __________
trypsinogen; trypisin
| within small intestine
113
what
converts chymotrypsinogen to chymotrypsin
trypsin
114
chymotrypsin digests
proteins
115
Pancreatitis
autodigestion
of pancreas brought on by
alcoholism
116
Severe, acute pancreatitis
can be fatal within
hours
117
What prevents the pnacreas from digesting itself?
enterokinase converts trypsinogen to trypsin, which converts chymotrypsinogen to chymotrypsin
| Cascade rxn
