Liver Function

Question 1

functions of the liver

Answer 1

carb, fat, protein, and hgb metabolism; form bile, detoxification

Question 2

where bile is made, stored, and where it goes

Answer 2

made in liver, stored in gallbladder (if species has one), goes to duodenum

Question 3

how bilirubin is formed

Answer 3

RBCs breakdown, heme portion is made into biliruben

Question 4

B1 vs B2

Answer 4

B1- unconjugated, fat soluble, indirect. Liver picks up and changes to B2 (conjugated, water soluble, direct) is excreted

Question 5

what causes yellow skin/MM in liver disease

Answer 5

Bilirubin build up in blood (icterus/jaundice)

Question 6

test used to differentiate indirect and direct bilirubin

Answer 6

Van den Bergh’s Rxn

Question 7

examples of pre-hepatic conditions that may increase bilirubin levels

Answer 7

RBC hemolysis

Question 8

examples of hepatic conditions that may increase bilirubin levels

Answer 8

liver disease (neoplasia, hepatitis, drugs, toxins)

Question 9

examples of post-hepatic conditions that may increase bilirubin levels

Answer 9

gall bladder issue, cholestasis (back up of bile into liver, usu. a bile duct obstruction like gall stones or neoplasia)

Question 10

In what species is alanine aminotransferase (ALT) used to detect liver disease?

Answer 10

d/c and humans

Question 11

T or F; the degree of change of ALT indicate the severity of liver disease

Answer 11

F

Question 12

name diseases or conditions that may lead to ALT increase

Answer 12

hepatitis, toxins, cancer, cholestasis, drugs that damage liver

Question 13

In what species is aspartate aminotransferase (AST) used to detect liver disease

Answer 13

all species

Question 14

where is AST found

Answer 14

not liver specific; also found in muscle

Question 15

what else do we measure when measuring AST

Answer 15

creatine kinase (CK) to differentiate muscle from liver damage (bc AST found in both liver and muscle)

Question 16

Why is SAP (serum alkaline phosphatase) found in so many organs?

Answer 16

catalyzes rxn that releases glucose from storage form, found in any cell that uses large amounts of glucose (liver, intestine, kidneys, bone and cartilage of young)

Question 17

Why may SAP be elevated in young animals, pregnant animals or animals with bone disease or fractures?

Answer 17

bone development in young and fetuses(found in cartilage/bone), placenta also high in SAP, also released for fracture repair

Question 18

Is gamma glutamyl transferase liver specific and in what animals can it be used to determine liver disease?

Answer 18

liver specific; can be used in all species

Question 19

Is sorbitol dehydrogenase (SDH) a good indicator of liver disease? What is the problem with measuring this enzyme?

Answer 19

it is high in the liver of all species but unstable and cannot store blood sample (will disappear)

Question 20

What is the problem with measuring lactate dehydrogenase (LDH) for liver disease

Answer 20

found in many tissues, not liver specific

Question 21

In what animals is GLDH most useful to evaluate liver disease?

Answer 21

if have liver disease, high amounts seen in birds, cattle, sheep, and goats

Question 22

Why are serum bile acids used to evaluate liver disease?

Answer 22

95% of bile acids reabsorbed by liver, a very small amount should be in circulation

Question 23

What genetic/ congenital defect can be detected using bile acid measurement

Answer 23

Portosystemic shunt not closing (liver is bypassed in fetuses by this shunt)

Question 24

why impaired liver function may not be determined until up to 80% of liver is involved

Answer 24

liver has large reserves and can regenerate