B5-017 Hepatic and Gallbladder Physiology Flashcards
1
Q
large capillary betwen plates of hepatocytes
A
liver sinusoids
2
Q
drains filtered blood into hepatic vein and IVC
A
central vein
3
Q
polarized parenchymal cells
A
hepatocytes
4
Q
bile duct epithelial cells
A
cholangiocytes
5
Q
liver resident macrophages
A
Kupffer cells
6
Q
fenestrated endothelial cells
A
sinusoidal endothelial cells
7
Q
- stores fat soluble vitamins
- produces collagen
A
stellate cells
8
Q
what types of metabolism occur in zone 1?
3
A
- fatty acid oxidation
- gluconeogenesis
- bile acid uptake
9
Q
what types of metabolism occur in zone 2?
A
- fatty acid synthesis
- glycolysis
- bile acid synthesis
10
Q
prevents reflux of duodenal contents into the pancreatic and bile ducts
A
spincter of Oddi
11
Q
three organic solutes important to bile formation
A
- cholesterol
- bile salts
- phospholipids
12
Q
- glycosylated protein forming gel lubrication barrier
- found in bile
A
mucin
13
Q
proteins found in bile
4
A
- IgA, IgM, IgG
- mucin
- albumin
- apolipoproteins
14
Q
precursor of sex hormones, arenal hormones, vitamin D, and bile acids
A
cholesterol
15
Q
hepatic cholesterol sources of input
A
diet
de novo synthesis
16
Q
hepatic cholesterol output
A
biliary secretion and bile acid synthesis
17
Q
rate limiting enzyme in cholesterol formation
A
HMG CoA reductase
statins inhibit
18
Q
major CYP pathway of cholesterol -> bile acid synthesis
A
CYP7A1
19
Q
primary bile acids
2
A
CDCA
CA
20
Q
secondary bile acids
2
A
DCA
LCA
21
Q
how much bile acid is eliminated through feces?
%
A
5%
22
Q
how much cholesterol is eliminated through feces?
%
A
50%
23
Q
secretion via I cells is stimulated by dietary fats and amino acids
A
CCK
24
Q
- stimulates gallbladder contraction
- relaxes spinchter of Oddi
A
CCK
25
* inhibits gastric secretion to promote digestion
* induces satiety
CCK
26
stimulates HMG CoA reductase and LDLR to increase de novo cholesterol synthesis and uptake of lipoprotein
| during low cholesterol
SREBP2
27
stimulates ABCG5/G8 and CYP7A1 to increase cholesterol catabolism and secretion
| during high cholesterol
LXR
28
induces FGF19 to inhibit CYP7A1 in hepatocytes
bile-acid activated FXR
29
bile activated FXR induces [...] to increase bile acid secretion
BSEP
30
bile activated FXR induces [...] to promote bile acid transport
OST/aB
31
bind negatively charge bile acids to prevent bile acid reabsorption
bile acid sequestrants
32
defects in micelle synthesis will cause
| 2
hypercholesterolemia
artherosclerosis
33
defects in the hepatic transport of mixed micelles will cause
cholestasis
34
defects in intestinal absorption with mixed micelles cause
chronic diarrhea
35
enzyme that converts unconjugated bilirubin to conjugated bilirubin
UGT
36
most common cause of neonatal cholestasis
biliary atresia
37
* elevated conjugated bilirubin
* jaundice
* first 8 weeks of life
* dark urine
* pale stool
biliary atresia
38
* male dominant
* average age of dx: 30-40
* associated with IBD
* p-ANCA
primary sclerosing cholangitis
39
* female dominant
* average age of diagnosis: 35-70
* associated with frequent UTIs
* AMA antibody
primary biliary cholangitis
40
* pruritis in 3rd trimester -> jaundice
* elevation of AST, ALT, bile acid
intrahepatic cholestatis of pregnancy
41
* progressive liver disease leading to liver failure
* genetic defects in bile secretion
* pruritis, jaundice, FTT, cirrhosis, portal HTN, hepatomegaly
progressive familial intrahepatic cholestasis
42
* defect in ATP8B1
* extrahepatic manifestations (diarrhea, pancreatitis, etc.)
* no gallstones
PFIC1 (byler disease)
43
* BSEP (ABC11) mutation
* gallstones
* high incidence of HCC and cholangiocarcinoma
PFIC2 (Byler syndrome)
44
* MDR3 (ABCB4) mutation
* gallstones
* elevated GGT
* decreased biliary phospholipids
PFIC3
45
* Mrp2 mutation
* elevated conjugated bili
* normal total urine coproporphyrin with elevated isomer I fraction
* black liver
Dubin-johnson syndrome
46
* OATP1B1/3 mutation
* elevated conjugated bilirubin
* elevated total urine coproporphyrin with Isomer I fraction
* visualized on oral cholecystography
rotor syndrome
47
* defect in UGT1A1
* extremely high unconjugated bilirubin
Crigler-Najjar Syndrome
48
* defect in UGT1A1
* elevated unconjugated bilirubin
* episodic jaundice under stress
Gilbert syndrome
49
most common reason for pediatric liver transplantation
biliary atresia
50
* newborn
* persistant jaundice after 2 weeks of life
* darkening urine
* acholic stools
* hepatosplenomegaly
biliary atresia
51
* asymptomatic/mild jaundice with stress, fasting, illness
* mildy decreased UDP glucuronosyltrasnferase conjugation
* relatively common, benign condition
Gilbert
52
* absent UDP-glucuronosyltrasnferase
* presents early in life, but may not have neurologic symptoms until later in life
* jaudice, kernicterus
* increased unconjugated bilirubin
Crigler-Najjar
| type 1, type 2 less severe
53
* conjugated hyperbilirubinemia due to defective liver excretion
* grossly black Dark liver due to impaired extretion of epinephrine metabolites
Dubin-Johnson syndrome
54
AMA is sensitive and specific for
PBC
55
occurs 3rd trimester and patients present with itching
intrahepatic cholestasis
56
* decreased biliary bile acid secretion causes intrahepatic accumulation of bile acids
* causes basolateral bile efflux and elevated serum bile acid
intrahepatic cholestasis
57
what test should be ordered if intrahepatic cholestasis is suspected?
fasting serum bile acids
58
RUQ ultrasound and MRCP can be used to rule out
extrahepatic biliary obstruction
59
* infant
* jaundice
* dark urine
* clay-colored stool
* elevated conjugated/direct bilirubin
congenital extrahepatic biliary atresia
60
causes gallbladder contraction and relaxation of ampulla of Vater leading to bile secretion
CCK
61
standard treatment for patients with acute cholecystitis
IV fluid, antibiotics, observe
62
if a patient with acute cholecystitis improves within 48 hrs,...
schedule elective cholecystectomy
63
procedure used to diagnose and treat problems in liver, gallbladder, bile ducts, pancreas
ERCP
64
used to dissolve small, non-calcified cholesterol gallstones in poor surgical candidates
UDCA
65
caused by Mrp2 mutation
Dubin-Johnson
66
loss of UGT1A1 causes
Gilbert's syndrome
67
Gilbert's syndrome is associated with elevated [...] bilirubin
indirect
68
Dubin-Johnson causes elevated [...] bilirubin
direct
69
caused by ATP8B1 mutation
PFIC1 (byler disease)
70
* elevated transaminases
* normal GGT
* elevated serum bile acid
* elevated indirect bilirubin
PFIC1
71
gold standard for diagnosis and treatment of common bile duct obstruction
ERCP
72
if cholangitis is suspected, what should be performed?
ERCP
73
charcot's triad has high specificity for
acute cholangitis
74
decreases pruritis
UDCA
75
acute cholangitis most commonly arises from
choledocholithiasis
| also can be caused by tumor or biliary stricture
76
epigastric pain
elevated lipase/amylase
pancreatitis
77
takes up bile acids at the apical side of the enterocyte
ASBT
78
takes up cholesterol at the apical side of the enterocyte
NPC1L1
| **then cholesterol effluxes out basolateral side and enters lymphatics**
79
effluxes cholesterol into lumen at apical side of enterocyte
ABCG5/G8
80
takes up bile acids into hepatocyte
NTCP
81
effluxes bile acids out basolateral side of enterocyte into portal circulation
OSTa/B
82
transports bilirubin into cannaliculi
MRP2
83
transports bile acids into cannaliculi
BSEP
84
transports phospholipids into cannaliculi
MDR3
85
transports cholesterol into cannaliculi
ABCG5/G8
