pcol 838a exam 1: liver diseases review
questions
from which vascular beds do the hepatic central veins derive their blood flow? -
ANS-portal vein and hepatic artery
blood flow: portal vein/hepatic artery -> central vein -> hepatic vein -> inferior vena cava
what cell types make up the liver, and what are their distinguishing characteristics? -
ANS-hepatocytes: metabolism
cholangiocytes: line the bile duct, secretion
kupffer cells: phagocytosis of pathogens and particles (dead cells)
stellate cells: storage of vit A
sinusoidal endothelial cells: filtering system
what is the difference between the lobule concept and the acinus concept of the liver
sub-architecture? - ANS-lobule
•anatomical unit of the liver in hexagonal shape
•central structure is central vein and the periphery is delineated by portal tracts
acinus
•functional unit of the liver
•divided into 3 zones
what are some physiological consequences of functional zonation in the liver? -
ANS-increase in metabolic efficiency
what activities are found in zone 1 hepatocytes? in zone 3 hepatocytes? - ANS-zone 1
•oxidative metabolism
•gluconeogenesis
•ureagenesis
zone 3
•glycolysis
•liponeogenesis
•xenobiotic metabolism
, what structures normally maintain the separation of apical and basolateral plasma
membrane domains of the hepatocyte? - ANS-junctional proteins
name and explain the four clearance or protective functions of the liver -
ANS-•phagocytic and endocytic functions of kupffer cells
•endocytic functions of hepatocytes
•ammonia metabolism
•hepatocytes synthesis of gluthiathione
*explanation in slides*
explain phase I and phase II reactions in drug detoxification - ANS-phase I: involve
oxidation, reduction, or hydrolysis of the parent drug, resulting in its conversion to a
more polar molecule
phase II: involve conjugation by coupling the drug or its metabolites to another
molecule, such as glucuronidation, acylation, sulfate, glycine
under what circumstances is hypoglycemia seen in liver disease? - ANS-decrease in
functional hepatocyte mass
what are the manifestations of liver dysfunction? - ANS-•diminished energy generation
and substrate interconversion
•loss of solubilization and storage functions
•diminished synthesis and secretion of plasma proteins
•loss of protective and clearance functions
what is the chemical that causes jaundice? - ANS-bilirubin
what are the mechanisms of jaundice? - ANS-•a defect in the capacity of the cell to trap
and absorb bilirubin
•the inability of the cell to conjugate bilirubin because of a deficiency in UGTs
•problems in the transfer and excretion of bilirubin glucuronide into the biliary canaculi
•obstruction of bile flow as a result of gallstones or tumors of the pancrease
name 4 clinical consequences of cholestasis - ANS-•malabsorption and deficiency
states due to a failure to solubilize dietary lipids and fat-soluble vitamins
questions
from which vascular beds do the hepatic central veins derive their blood flow? -
ANS-portal vein and hepatic artery
blood flow: portal vein/hepatic artery -> central vein -> hepatic vein -> inferior vena cava
what cell types make up the liver, and what are their distinguishing characteristics? -
ANS-hepatocytes: metabolism
cholangiocytes: line the bile duct, secretion
kupffer cells: phagocytosis of pathogens and particles (dead cells)
stellate cells: storage of vit A
sinusoidal endothelial cells: filtering system
what is the difference between the lobule concept and the acinus concept of the liver
sub-architecture? - ANS-lobule
•anatomical unit of the liver in hexagonal shape
•central structure is central vein and the periphery is delineated by portal tracts
acinus
•functional unit of the liver
•divided into 3 zones
what are some physiological consequences of functional zonation in the liver? -
ANS-increase in metabolic efficiency
what activities are found in zone 1 hepatocytes? in zone 3 hepatocytes? - ANS-zone 1
•oxidative metabolism
•gluconeogenesis
•ureagenesis
zone 3
•glycolysis
•liponeogenesis
•xenobiotic metabolism
, what structures normally maintain the separation of apical and basolateral plasma
membrane domains of the hepatocyte? - ANS-junctional proteins
name and explain the four clearance or protective functions of the liver -
ANS-•phagocytic and endocytic functions of kupffer cells
•endocytic functions of hepatocytes
•ammonia metabolism
•hepatocytes synthesis of gluthiathione
*explanation in slides*
explain phase I and phase II reactions in drug detoxification - ANS-phase I: involve
oxidation, reduction, or hydrolysis of the parent drug, resulting in its conversion to a
more polar molecule
phase II: involve conjugation by coupling the drug or its metabolites to another
molecule, such as glucuronidation, acylation, sulfate, glycine
under what circumstances is hypoglycemia seen in liver disease? - ANS-decrease in
functional hepatocyte mass
what are the manifestations of liver dysfunction? - ANS-•diminished energy generation
and substrate interconversion
•loss of solubilization and storage functions
•diminished synthesis and secretion of plasma proteins
•loss of protective and clearance functions
what is the chemical that causes jaundice? - ANS-bilirubin
what are the mechanisms of jaundice? - ANS-•a defect in the capacity of the cell to trap
and absorb bilirubin
•the inability of the cell to conjugate bilirubin because of a deficiency in UGTs
•problems in the transfer and excretion of bilirubin glucuronide into the biliary canaculi
•obstruction of bile flow as a result of gallstones or tumors of the pancrease
name 4 clinical consequences of cholestasis - ANS-•malabsorption and deficiency
states due to a failure to solubilize dietary lipids and fat-soluble vitamins
