Liver 1 (test 1)

Question 1

T or F

Liver lesions are much more common than liver failure

Answer 1

True: diffuse disease, rather than focal lesions, is required to produce failure

Question 2

How much of your liver do you need to function and still be alive?

Answer 2

~30%

Question 3

What is the most frequently injured organs in the body?

Answer 3

The Liver

Question 4

Can the Liver regenerate?

Answer 4

yes it can, but its not considered true regeneration-compensatory growth

Question 5

When do you see clinical signs of liver disease?

Answer 5

When the reserve is exhausted. The onset of signs may be acute, but are often the end result of chronic disease.

Question 6

What is the largest gland in the body?

Answer 6

The Liver!

Question 7

What allows the liver to avoid infarction?

Answer 7

Because of its DUAL blood supply

Question 8

Where does the portal vein receive blood?

Answer 8

From the GI tract and the Spleen

Question 9

T or F

Mixing of arterial and venous blood in the sinusoids increases the O2 of hepatic blood, but overall this is a High oxygen system

Answer 9

False, this is a low oxygen system: 50% O2 from hepatic artery, 50% O2 from portal vein

Question 10

Which animal doesn’t have a gallbadder?

Answer 10

The Horse, so you won’t be diagnosing them with a cholecystitis

Question 11

Which cell makes up of 94% of hepatic cells?

Answer 11

Hepatocytes

Question 12

What makes up a portal triad?

Answer 12

Hepatic arteriole, portal venule, bile duct

+ lymphatic vessels

Question 13

Label this microscope slide

A.

B.

C.

D.

Answer 13

A. Portal Vein

B. Bile Duct

C. Lympatic vessel

D. Hepatic Artery

Question 14

Where does blood enter in the liver?

Answer 14

Blood enters lobule via portal triads and flows toward CENTRAL veins through the hepatic sinusoids

Question 15

What is hepatic sinusoids lined by?

Answer 15

FENESTRATED endothelium

Hepatocytes are in direct contact with plasma

Question 16

What is the name of the APC cells in the Liver?

Answer 16

Phagocytic Kupffer Cells (tissue macrophages)

Question 17

What is the purpose of stellate cells in the liver?

Answer 17

They are involved in vit. A storage and sinusoidal blood flow regulation. Can synthesize collagen when activated (important role in hepatic fibrosis)

They reside in the space of Disse (space between endothelium and hepatocytes)

Question 18

Which cells receives the most O2 in the liver?

A. Periportal Cells

B. Centrilobular Cells

Answer 18

Periportal cells: they are exposed to blood that first enters lobule, thus receiving the most O2

Question 19

Where is a majority of the metabolizing enzyme system (drug and toxin metabolism)?

Answer 19

In the smooth ER of the centrilobular hepatocyes

Question 20

Where does bile flow in relation to blood flow?

Answer 20

It flows in the opposite direction of blood flow

Question 21

where is bile secreted in the liver?

Answer 21

into canalculi

(formed by tight junctions between adacent hepatocytes, lead to protal triads and bile ductules)

Question 22

Define Cholestasis

Answer 22

It is the stasis or reduced flow of bile often due to damged hepatocytes

Question 23

What does the secretion of bile require because it is an active process?

Answer 23

It requires ATP

Any injury tat causes significant hepatocellular injury can inhibit bile secretion

Question 24

What are the two models for the microarchitecture of the liver?

Answer 24

The lobule model

The acinar model

Question 25

Define Metabolic hertogeneity in the liver

Answer 25

It means that the concentration of enzymes also change across the lobule

Question 26

Where would you most likely see ischemic tissue in the liver due to hypoxia?

Answer 26

In the Centrilobular Region

Question 27

Equine piroplasmosis is caused by one of two tick transmitted hemoprotozoal parasites that invade and destroy erythrocytes to complete their life cycle. Laboratory findings may include profound anemia, icterus, hemoglobinuria, and mild to moderately elevated liver enzymes. The gross lesions often include icterus and splenomegaly. What is the most likely cause of the increased liver enzymes? A. Hepatocellular damage due to infection of hepatocytes B. Hypoxia of centrilobular hepatocytes due to anemia C. bile duct obstruction D. Occlusion of the hepatic artery

Answer 27

B. Hypoxia of centrilobular hepatocytes due to anemia (iron deficiency)

Question 28

What are the functions of the Liver?

Answer 28

A. Detoxification of endogenous and exogenous compounds B. synthesis of plasma proteins (e.g. albumin and clotting factors) C. Secretion and conduction of bile (exretion of detoxified compounds, and secretion of bil salts (for enteric fat solubilization)) D. Energy metabolism (Lipids and carbs) E. Surveillance of hepatoportal blood (kupffer cells) (immune function) F. Secondary role in salt and water homeostasis

Question 29

What is an endogenous toxin that the liver detoxifies?

Answer 29

Ammonia-which is a result of nitrogen from protein breakdown

Question 30

What are examples of exogenous toxins cleared by the liver?

Answer 30

Chlorophyll (herbivores), drugs

Question 31

What produces ammonia?

Answer 31

Bacteria in the large bowl mostly and also by deamination of amino acids

Question 32

What does the liver do with ammonia when it is functioning properly?

Answer 32

It converts it to urea which is than eliminated in the urine

Question 33

True or False Hepatic Encephalopathy is considered a diagnosis

Answer 33

FALSE It is considered a clinical sign which can be represented by: head pressing, depression, disorentation, ataxia, seizures, dementia, blindness, prolonged recovery from anesthesia

Question 34

How do you treat for hepatic encephalopathy?

Answer 34

Diet: give low protein (decreased production of ammonia and other neurotoxins) GI acting antibiotic--\>decrease GI flora and decrease ammonia production Lactulose: synthetic dissacharide metabolized by LI bacteria--\> lactic acid formation--\>decreased colonic pH--\>traps intestinal NH4+

Question 35

When could you see chlorophyl toxicity in animals?

Answer 35

With Intrahepatic cholestsis (reduced bile flow) or severe hepatocellular injury Becasue phylloerythrin is not metabolized, it accumulates in the blood, binds to cells in the skin . Normally absorbed and excreted in bile

Question 36

What is a clinical sign as a result of phylloerythrin toxicity due to poor liver detoxification?

Answer 36

UV irradiation to non-pigmented areas of skin causes fluorescent pigment to emit damaging radiation at a longer wavelength--\> inflammation and necrosis--\>produces dermatitis--\>Secondary (hepatogeous) **PHOTOSENSITIZATION**

Question 37

What plasma proteins is the liver responsible for producing ?

Answer 37

Albumin: synthesized exclusively by hepatocytes (oncotic pressure, carrier proteins, etc) Clotting Factors

Question 38

What is a consequence of dysfunction in the liver in regards to plasma protein synthesis?

Answer 38

Clotting factor deficiency: Coagulopathy Hypoalbuminemia: edema, ascites, abnormal drug metabolism (insensitive measure of function, requries severe injury/loss of hepatocytes)