Hepatobiliary system Flashcards

1
Q

What are the two primary lobes of the liver?

A

Right and left

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2
Q

Which folds connect the liver to the abdominal wall and diaphragm?

A

Pertioneal folds (ligaments)

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3
Q

What vessel delivers the majority of blood to the liver?

A

Hepatic portal veins

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4
Q

Which vessels deliver blood to the liver?

A

Hepatic portal veins

Hepatic artery

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5
Q

What % of blood flow arises from the hepatic artery into the liver?

A

25%

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6
Q

What is the hepatic artery?

A

Delivers oxygenated blood from the heart to the liver

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7
Q

What is the hepatic portal vein?

A

Delivers partially deoxygenated blood containing nutrients and toxins absorbed from the small intestine, pancreas, gall bladder and spleen to the liver

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8
Q

What is the main outflow of the liver?

A

There are 3 hepatic veins (right, middle and left), these drain into the inferior vena cava

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9
Q

The right and left hepatic duct converge to form which duct?

A

The common hepatic duct

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10
Q

Where do the right and left hepatic ducts converge?

A

The hilum

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11
Q

Which duct does the common hepatic duct converge with to form the common bile duct?

A

The cystic duct

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12
Q

What is the primary function for the common bile duct?

A

Carry bile to the duodenum of the small intestine. Bile produced by the liver is pushed back up the cystic duct y peristalsis to arrive in the gallbladder for storage.

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13
Q

What are the three main hepatic veins?

A

Right hepatic vein
Middle hepatic vein
Left hepatic vein

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14
Q

What is the middle hepatic vein, and its role in liver anatomy?

A

Obliquely runs from the inferior vena cava to the gallbladder fossa. Separates the anterior and medial segments of the right hepatic lobe.

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15
Q

What is the right hepatic vein and its anatomical divisions?

A

Divides anterior and posterior segments of the right hepatic lobe

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16
Q

What is the left hepatic vein and its anatomical divisions?

A

Left hepatic vein separates the medial and lateral segments of the left hepatic lobe

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17
Q

Where do the 3 hepatic veins drain into?

A

Inferior vena cava

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18
Q

Which ligament separates the lateral and medial segments?

A

Ligamentum teres

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19
Q

In which direction are segments II - VII numbered?

A

Clockwise fashion

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20
Q

What are the three main components of the liver?

A

Hepatocytes
Bile canaliculi
Hepatic sinusoids

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21
Q

What are the main hepatic cells?

A

Hepatocytes

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22
Q

What term is used to describe plates of hepatocytes?

A

Hepatic laminae

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23
Q

What are hepatic laminae?

A

Plates of hepatocytes.Hepatic laminae radiate outward from the portal vein in each hepatic lobule.

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24
Q

What is in the central of the hepatic lobule?

A

Central vein

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25
Q

What is the central vein in the hepatic lobule?

A

Collects blood from the hepatic sinusoids –> hepatic vein to the inferior venous cava

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26
Q

What are the two side faces of the lobule hepatocyte rows?

A

Sinusoid facing side, and bile canaliculi facing side

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27
Q

What is the function performed by bile canaliculi?

A

Adjacent hepatocytes, grooves in cell surface membrane provides bile canaliculus  Accumulate bile produced by hepatocytes. Bilirubin processed & excreted into bile canaliculi.

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28
Q

What is a hepatic sinusoid?

A

Open porous blood space formed by sinusoidal capillaries from hepatic portal veins.Hepatocytes are densely packed around sinusoidal epithelium, proving accessibility to blood supply

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29
Q

What is a portal triad?

A

Arrangement around perimeter of hepatic lobules, consists of: Bile duct, hepatic artery branch, and a hepatic portal vein.

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30
Q

How many hepatic lobules are linked by a portal triad?

A

3 hepatic lobules

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31
Q

Describe the movement of bile through the ducts:

A

Bile flows into bile ductules  Bile duct  Right & left hepatic ducts  Common hepatic duct + Cystic duct (from gallbladder)  Common bile duct.

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32
Q

What is the role of the hepatic artery?

A

Delivers oxygenated blood into the live to support the metabolic demands of hepatocytes

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33
Q

Where does the portal vein arise from?

A

Mixed venous blood from the gastrointestinal tract (nutrients, bacteria & toxins), and spleen (metabolic waste substrates).
Hepatocytes process nutrients, detoxify & excrete waste.

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34
Q

What is the main outflow of the hepatic lobule?

A

Bile produced from hepatocytes drains into bile canaliculi, these ducts coalesce with cholangiocyte-lined bile ducts present around lobule perimeter

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35
Q

What is a hepatic acinus?

A

Consists of 1/6th of hepatic lobule, comprises of two portal triads extending into the hepatic lobule towards the central vein

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36
Q

Where does the central vein reside in relation to the acinus?

A

Resides within the acinus apex.

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37
Q

How many zones comprise a hepatic acinus?

A

Three

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38
Q

Which hepatic acinus zone has the greatest oxygen concentration?

A

Zone 1

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39
Q

Which hepatic acinus zone has the lowest oxygen concentration, and lowest toxin risk?

A

Zone 3

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40
Q

Describe the structure of sinusoidal endothelium?

A

Absence of basement membrane
The endothelium is fenestrated (discontinuous), therefore increasing permeability to substrate, facilitating the movement of lipids and substrates to and from hepatocytes

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41
Q

Which cells are attached to the sinusoidal endothelium?

A

Kupffer cells

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42
Q

What are Kupffer cells?

A

Kupffer cells are attached to the sinusoidal endothelium exhibiting the capacity to undergo phagocytosis, agonistically functioning as sinusoidal macrophages  Eliminating & detoxifying substances arriving in liver from portal circulation.
Hemosiderin store  Available production of haemoglobin.

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43
Q

Which hepatic cells store vitamin A?

A

Stellate cells

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44
Q

What are hepatic stellate cells?

A

Hepatic stellate cells reside within the perisinusoidal space, the Space of Disse. Exist in quiescent state, providing available storage of Vitamin A in cytosolic droplets.
Stellate cells undergo activation in response to hepatic damage, expressing fibroblast activity  Proliferate, chemotactic & deposit collagen in extra-cellular matrix.

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45
Q

What are hepatocytes?

A

Cubical cells responsible for the synthesis of albumin, clotting factors & bile salts. Site of drug metabolism; receives nutrients & substrates from sinusoids.
80% of liver mass

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46
Q

Where do cholangiocytes reside?

A

On the edge of the bile duct, secrete bicarbonate and water in bile

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47
Q

What do cholangiocytes secrete?

A

Bicarbonate & water into bile

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48
Q

What are the main functions of hepatocytes?

A

Metabolic & catabolic functions: Synthesis & utilisation of carbohydrates, lipids and proteins.
Secretory & excretory function: Synthesis and secretion of proteins, bile & waste prodcuts
Detoxification & immunological functions: Degradation of ingested pathogens, and processing of drugs
Carbohydrate metabolism

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49
Q

What is glycolysis?

A

Glycolysis: Anaerobic conversion of glucose  Lactate (RBCs, renal medulla & skeletal muscle); aerobic oxidation of glucose  Pyruvate (CNS, heart, skeletal muscle).

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50
Q

What is glycogenesis?

A

Synthesis of glycogen from glucose (Liver & muscle)

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51
Q

What is glycogenolysis?

A

Breakdown of glycogen to glucose

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52
Q

What is gluconeogenesi?

A

Gluconeogenesis: Production of glucose from non-sugar substrates: Amino acids (glutamine) in liver & renal cortex; lactate (from anaerobic glycolysis in RBCs & muscles); glycerol from lipolysis.

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53
Q

What is lipolysis?

A

Hydrolysis of triacylglycerols into glycerol and free fatty acids

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54
Q

What is lipoegenesis?

A

Synthesis of triacylglycerols (storage in adipose tissue)

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55
Q

Which cycle converts lactate into pyruvate?

A

The Cori cycle

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56
Q

What is the Cori cycle?

A

Refers to the metabolic pathway in which lactate produced through anaerobic glycolysis in the myocyte is transported to the liver under The action of lactate dehydrogenase to form pyruvate
Converted into glucose via gluconeogenesis

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57
Q

Where do amino acids undergo protein synthesis?

A

Within the liver

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58
Q

What proteins are formed within the liver?

A

Lipoproteins
Plasma proteins (albumin)
Clotting factors

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59
Q

Which enzyme are involved in the conversion of amino acids?

A

Transaminases

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60
Q

Alpha keto-glutarate can be converted into which 3 amino acids?

A

Glutamine
Proline
Arginine

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61
Q

Pyruvate can be converted into which 3 amino acids?

A

Alanine, valine and leucine

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62
Q

What amino acid is pyruvate transaminate into in the glucose-alanine cycle?

A

Alanine

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63
Q

What type of amino acid is alanine?

A

Glucogenic amino acid

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64
Q

How is pyruvate converted into alanine?

A

The amino group on glutamate is transferred to pyruvate by aminotransferase generating alpha-keto-glutarate, and converting pyruvate to alanine

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65
Q

How is nitrogen transported to the liver?

A

Nitrogen is also transported to the liver in form of glutamine, synthesised from glutamate and ammonia in reaction catalysed by glutamine synthetase  Ammonia released through action of glutaminase.

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66
Q

Which cells stored triglycerides?

A

Adipocytes

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67
Q

Which enzymes hydrolyse triglycerides into fatty acids in adipose tissue?

A

Hormone sensitive lipase

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68
Q

How are fatty acids shuttled into the liver?

A

Carnitine shuttle

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69
Q

What is the fate of fatty acids in the liver?

A

Undergo beta oxidation, into acetyl CoA, enters into the TCA cycle or substrate for ketogenesi

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70
Q

What is the main energy store within the liver?

A

Glycogen

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71
Q

What happens when glycogen hepatic storage reaches maximum capacity?

A

Results in glucose and amino acid conversion into triglycerides as storage within liver and adipose tissue.

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72
Q

2 molecules of acetyl-CoA form what compound?

A

Acetoacetate

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73
Q

How are lipids, triacylglyerols and cholesterol transported?

A

Lipoproteins

74
Q

What are lipoproteins?

A

globular micelle like particles that consist of nonpolar core of triacylglycerols, and cholesteryl-esters surrounded by an amphiphilic coating of protein, phospholipid & cholesterol.

75
Q

Which molecules transports triacylglycerols and cholesterol from small intestines to tissues?

A

Chylomicrons

76
Q

Which lipoproteins transport endogenous triacylglycerols and cholesterol from the liver to tissues?

A

LDLs
IDLs
VLDls

77
Q

What are HDLs?

A

High density lipoproteins, transport endogenous cholesterol from tissues to the liver

78
Q

What is the lipoprotein synthesis pathway?

A

𝑮𝒍𝒖𝒄𝒐𝒔𝒆→𝑷𝒚𝒓𝒖𝒗𝒂𝒕𝒆 →𝑨𝒄𝒆𝒕𝒚𝒍−𝑪𝒐𝑨 →𝑭𝒂𝒕𝒕𝒚 𝒂𝒄𝒊𝒅𝒔 & 𝑪𝒉𝒐𝒍𝒆𝒔𝒕𝒆𝒓𝒐𝒍

𝑮𝒍𝒖𝒄𝒐𝒔𝒆 →𝑮𝒍𝒚𝒄𝒆𝒓𝒐𝒍

𝑮𝒍𝒖𝒄𝒐𝒔𝒆+𝟑 𝑭𝒂𝒕𝒕𝒚 𝒂𝒄𝒊𝒅𝒔 →𝑻𝒓𝒊𝒂𝒄𝒚𝒍𝒈𝒍𝒚𝒄𝒆𝒓𝒐𝒍+𝑨𝒑𝒐𝒑𝒓𝒐𝒕𝒆𝒊𝒏 𝒑𝒉𝒐𝒔𝒑𝒉𝒐𝒍𝒊𝒑𝒊𝒅𝒔+𝒄𝒉𝒐𝒍𝒆𝒔𝒕𝒆𝒓𝒐𝒍 →𝑪𝒉𝒚𝒍𝒐𝒎𝒊𝒄𝒓𝒐𝒏𝒔

79
Q

What are the three main functions of cholesterol?

A

Stabilisation and membrane integrity through fluid dynamics within the phospholipid bilayer
Steroidgenesis (mineralcorticoids, cortisol, and aldosterone)
Vitamin K synthesis (essential for clotting factors)

80
Q

Which clotting factors are reliant on vitamin K?

A

II, VII, IX, X

81
Q

Which fat soluble vitamins are stored by hepatocytes?

A

A, D, E, K

82
Q

Where is vitamin b12 stored?

A

Within hepatocytes

83
Q

Where is copper stored?

A

Within hepatocytes

84
Q

How long are the fat soluble vitamins stored for within hepatocytes?

A

6-12 months except Vitamin K

85
Q

How is iron stored within the liver?

A

As ferritin and hemosiderin

86
Q

What is haemochromatosis associated with?

A

Elevated iron levels

87
Q

Which enzymes are involved in detoxification?

A

P450 enzymes

88
Q

What is phase 1 of detoxification?

A

Modification, p450 enzymes are the predominant catalysts of phase 1 metabolism in liver. Phase 1 reactions are classified into: Oxidation, reduction & hydrolysis

89
Q

What is the purpose of phase 1 detoxification?

A

More hydrophilic xenobiotics

90
Q

What is oxidation in terms of xenobiotic metabolism?

A

Addition of oxygen into xenobiotic

91
Q

What is phase 2 of detoxification?

A

Conjugation

92
Q

What happens during the conjugation (Phase II) phase of detoxication?

A

Activated xenobiotic metabolites are conjugated with a charged polar species
Products of conjugation reactions have increased molecular weight, tend to be less active
The addition of large anionic groups detoxifies reactive electrophiles, and produces more polar metabolites that cannot diffuse across membranes, thus are active transported

93
Q

Where do right and left hepatic ducts converge?

A

At the hepatic hilum (portages hepatitis)

94
Q

The right and left hepatic duct converge together to form what?

A

The common hepatic duct

95
Q

Which duct converges with the common hepatic duct to form the common bile duct?

A

The cystic duct arising from the gall bladder

96
Q

Where does the common bile duct converge with the main pancreatic duct?

A

Ampulla of Vater

97
Q

Which spinchter regulates the entry of bile and pancreatic secretions into the duodenum?

A

The Sphincter of Oddi

98
Q

What forms the majority of bile?

A

Water 97%

99
Q

What colour is bilirubin?

A

Yellow-brownish pigment

100
Q

What colour is biliverdin?

A

Green

101
Q

Which cells secrete bile?

A

Cholangiocytes and hepatocytes

102
Q

What components and molecules are essential for the emulsification of lipids?

A

Bile salts & phospholipids

Exhibit hydrophobic and hydrophilic properties

103
Q

What is the function of the hydrophobic and hydrophilic regions of bile?

A

Interacts with large lipid molecules whereas the hydrophilic regions interacts with the watery chyme within the duodenum

104
Q

How are bile salts reclaimed?

A

Reclaimed by enterohepatic circulation, bile in ileum absorbed and returned to liver in the hepatic portal blood system

105
Q

What are the three main functions of bile?

A

Cholesterol homeostasis
Absorption of lipids & lipid soluble vitamins (A,D,E & K)
Excretion of: Xenobiotics, cholesterol metabolic, steroid hormones & alkaline phosphatases

106
Q

What % bile secretion is attributed to hepatocytes?

A

60%

107
Q

What function do cholangiocytes perform in secondary modification of bile?

A

Cholangiocytes lining the bile duct modify the canalicular bile, altering the pH (alkaline electrolyte solution), water is drawn into bile by osmosis via paracellular junctions. Canalicular bile enters the lumen of the canals of Hering, percolating towards the Cholangiocytes. These processes includes the active secretion of Cl- and HCO3- into the bile by CFTR proteins (Cystic fibrosis transmembrane regulatory).
Luminal glucose & organic acids reabsorbed
IgA exocytosis

108
Q

Which protein transporter secretes bicarbonate ions into the bile?

A

CFTR proteins

109
Q

What immunoglobulin is exocytosed by cholagiocytes?

A

IgA

110
Q

What is the main biliary transporter?

A

Bile salt excretory pump (BSEP): Active transport of bile acid into bile

111
Q

What is the function of MDR3?

A

Excretion of phosphatidylcholine

112
Q

What is the function of MDR1?

A

Excretion of xenobiotics and cytotoxins into the bile

113
Q

Which transporter located on the basolateral membrane transports bile salts & xenobiotics from the sinusoidal blood into the hepatocytes?

A

OATP transporters

114
Q

What are OATP transporters?

A

OATP transporters present on the basolateral membrane transport bile salt & xenobiotics from the sinusoidal blood (portal) into the hepatocyte.

115
Q

What are NTCP transporters?

A

Sodium dependent uptake transporters are expressed on the basolateral membrane
Uptake of bile salts from sinusoidal blood

116
Q

Which is the main precursor of bile salts?

A

Cholesterol

117
Q

Describe the pathway of cholic acid formation?

A

Cholesterol -> 7-alpha hydroxycholesterol -> cholic acid

118
Q

What are the two primary bile salts?

A

Cholic acids

Chenodeoxycholic acid

119
Q

What is the pathway of chenodeoxycholic acid formation?

A

Alternative pathway: Cholesterol  27-hydroxycholesterol (CYP27A-1)  Chenodeoxycholic acid (CYP7B1).

120
Q

Where are the primary bile salts synthesised?

A

Within hepatocytes & cholangiocytes

121
Q

Where are the primary salts secreted into?

A

Through the common bile duct into the duodenum via the ampulla of Vater

122
Q

Which ion salts are conjugated in the liver to glycine & taurine?

A

Sodium and potassium ion salts

123
Q

What are the two main secondary bile salts?

A

Deoxycholic acid

Lithocholic acid

124
Q

Where does primary bile salt biotransformation occur?

A

Occurs within the duodenum and jejunum by intestinal bacteria

125
Q

What is the function of bile salts in terms of fats?

A

Reduces surface tension of fats - emulsification of lipids prior to digestion an absorption

126
Q

What do bile salts form?

A
Bile salts form micelles *(steroid nucleus planar), exhibits amphiphatic characteristics 
Hydrophilic domains (carboxyl and hydroxyl groups) are externally exposed forming hydrogen bonds with water, and subsequently dissolving 
Hydrophobic domain *nucleus and metal components
127
Q

What is encapsulated within the micelles?

A

FFAs and cholesterol, dissolve in lipids

128
Q

what is the mechanism of fat globule lipid absorption?

A

Fat globules within the duodenum & jejunum are emulsified by bile salts & phospholipids  Increases available surface area & binding sites for lipases (in conjunction with colipase) to hydrolyse the lipids into fatty acids & glycerol.

129
Q

Which enzyme assists lipase in the hydrolysis of lipids?

A

Colipase

130
Q

Which substrates stimulate CCK release?

A

Peptids and fatty acids

131
Q

Which cells release CCK?

A

Enteroendocrine I mucous cells within the duodenal during the intestinal phase

132
Q

When is CCK released during the gastric phases?

A

Intestinal phase formulating the enteric inhibitory phase

133
Q

What effect does CCK have on the gall bladder?

A

Stimulates gall bladder contraction, facilitating the movement of bile through the common bile duct into the duodenum via the ampulla of Vater, this action is potentiated by the relaxation of the Sphincter of Oddi

134
Q

Which sphincter relaxes in response to CCK stimulation?

A

Sphincter of Oddi

135
Q

Which receptor is activated by CCK action?

A

CCKI receptor

136
Q

What state is the Sphincter of Oddi in, pre-prandially?

A

Constricted- coxed state, bile is diverted upwards through the cystic duct into the gall bladder for storage

137
Q

Where is 95% of bile salts absorbed?

A

Absorbed from the terminal ileum through the Na+/Bile salt co-transport Na+/K+ ATPase system

138
Q

Which transporters causes enterocyte absorption of bile salts?

A

ABST

139
Q

Which channels do bile salts enter through into portal venous circulation?

A

OST channels

140
Q

Which transporters are used for bile salt uptake?

A

OATP-1 transporters on the basolateral membrane to resyntheise into bile

141
Q

What is the fate of 5% of bile salts within the ileum?

A

Dehydroxylated undergoing modification into secondary bile salts within the colon

142
Q

Which secondary bile salt is absorbed?

A

Deoxycholic acid

143
Q

Which secondary bile salt is excreted into the stool?

A

Lithocholic acid is excreted in the stool

144
Q

Where does the gallbladder reside?

A

Resides within the posterior aspect of the right lobe of the liver

145
Q

What are the three main regions of the gall bladder?

A

Fundus
Neck
Cystic duct

146
Q

What cell types form the gallbladder?

A

Simple columnar epithelium of the gallbladder mucosa is organised in rugae
There is no subbmucosa within the gall bladder wall

147
Q

Which layer do the smooth muscle fibres reside within?

A

Muscular layer

148
Q

Which receptors does CCK bind onto to cause gall bladder wall contraction?

A

CCKa receptors and neural plexus

149
Q

What is the main role performed by the mucosa wall of the gallbladder?

A

Mucosa absorbs water and ions from the bile, concentrates and acidifies the bile 10 -fold

150
Q

Where is 75% if bilirubin formed from?

A

Erythrocytes

151
Q

How are erythrocytes converted into unconjugated bilirubin?

A

Removed from circulation within the spleen, under the activity of haem oxygenase, the haem group is cleaved oxidatively to form biliverdin - central methanyl bridge is reduced into bilirubin

152
Q

What are the 3 main sources of bilirubin?

A

RBCs 75%
Catabolism of alternative haemoproteins (cytochromes) 22%
3% from ineffective bone marrow erythropoiesis>

153
Q

How is bilirubin transported within the blood?

A

Albumin plasma protein

154
Q

Which cells absorb bilirubin?

A

Hepatocyte

155
Q

Which molecules does bilirubin conjugate with within hepatocytes?

A

2 molecules of UDP-Glucuronic acid under the action of glucronyl-transferase –> Bilirubin diglucuronide (Direct BR)

156
Q

What is the name of conjugated bilirubin?

A

Bilirubin diglucuronide (Direct BR)

157
Q

Which transporter actively transported direct BR into the biliary canaliculi?

A

cMOAT transporter

158
Q

Which bilirubin is water insoluble?

A

Unconjugated bilirubin

159
Q

What % of bilirubin is excreted into faeces?

A

85%

160
Q

What is the fate of bilirubin in the faeces?

A

Bacterial enzymes in the large intestine hydrolyse the glucuronic acid groups in a multistep process  Urobilinogen (colourless & odourless)  Stercobilinogen  Stercobilin (Brown pigment)

161
Q

Which compound is responsible for the brown pigment in faecal matter?

A

Stercobilin

162
Q

Why does obstructive jaundice result in white stools?

A

No bile into large bowel therefore no bilirubin to be converted into stercobilin (White stools)

163
Q

What % of bilirubin enter into enterohepatic circulation?

A

14% enters enterohepatic circulation: BR  Deconjugated into lipophilic form (Urobilinogen & Stercobilinogen).

164
Q

What molecules arising from bilirubin is excreted by the kidneys?

A

Urobilin

165
Q

What are the 3 types of jaundice?

A

Prehepatic
Intrahepatic
Post-hepatic

166
Q

What is jaundice?

A

Characterised by elevated unconjugated serum bilirubin levels -> Yellowish pigmentation

167
Q

What are the main causes of prehepatic jaundice?

A

Bilirubin production is exaggerated due to erythrocyte abnormalities and degradation within the spleen, this potentiates the haem oxygenase activity in cleaving the haem groups to resultantly form unconjugated bilirubin. Conditions which are associated with this include: Sickle cell anaemia & hereditary spherocytosis

168
Q

What are the main causes of intrahepatic jaundice?

A

Intrahepatic jaundice is affiliated with dysfunctional hepatocytes. This includes:
Dysfunctional transporter proteins to intake indirect serum bilirubin from albumin
Decreased conjugation ability (Glucuronyl transferase inactivation)
Decreased outflow of conjugated bilirubin from hepatocytes (cMOAT inactivation or obstruction within biliary tree (canaliculi).

169
Q

What are the main causes of post-hepatic jaundice?

A

Interruption to the drainage of bile containing conjugated bilirubin in the biliary system. Associated causations include gallstones in the common bile duct, and pancreatic cancer in the head of the pancreas.

170
Q

What are gall stones?

A

Gall stones are crystalline masses formed abnormally within the gal bladder of bile ducts from bilirubin, cholesterol and calcium salts

171
Q

What is cholecystitis?

A

Inflammation of the gall bladder

172
Q

What is cholelithiasis?

A

The formation of gall stones resulting in obstruction within the bile ducts. Gallstone obstruction within the cystic duct causes Mirizzi’s syndrome.

173
Q

What is Mirizzi’s syndrome?

A

Gallstone obstruction within the cystic duct

174
Q

What are the common obstruction sites for gal stones?

A

Cystic duct
Common bile duct
Hepatopancreatic duct
Main pancreatic duct

175
Q

What is cholangitis?

A

Bacterial infection associated with the common bile duct

176
Q

What does ERCP mean?

A

Endoscopic retrograde cholangiopancreatography

177
Q

What is ERCP?

A

A procedure used to diagnose diseases of the gallbladder, biliary system, pancreas & liver. The procedure identifies upstream through the main pancreatic duct, common bile duct towards the biliary system in comparison to entrance through the Ampulla of Vater within the duodenum.
Wires can be inserted into the common bile duct to assist with the removal of obstructive bile stones within the common bile ducts, this can be identified using contrast dyes (cholangiogram) (Obstruction = black).

178
Q

What is spincterotomy?

A

Small incision of the sphincter of Oddi within the Ampulla of Vater, can help remove small gallstones

179
Q

How can a stent placement relieve gall stones?

A

Stent is a drainage tube that misplaced in the bile duct or the pancreatic duct to hold the duct open allowing it to drain

180
Q

What is the main limitation of gallstone removal using ERCP?

A

ERCP remove gall stones from bile duct not gallbladder itself.

181
Q

What does PTC mean?

A

Percutaneous Transhepatic Cholangiography