Liver Flashcards
regions
right hypochondriac, epigastric and left hypochondriac
where does the base lie
at the right costal margin, apex of the wedge extends into the left hyporchondrium
superior and inferior
diaphragm and ant abdominal wall
posterior
IVC, aorta, GB, vertebral column, diaphragm and oesophagus
lateral
lower ribs and diaphragm
inferior
stomach, bile ducts, duodenum, hepatic flexure of the colon, right kidney and adrenal gland
impressions
colic: hepatic flexure of the colon
tuber: lesser curvature of stomach
gastric
renal: right kidney
duodenal
what are the types of ligaments
falciform
round
coronary
triangular
ligaments role
anchors liver to diaphragm
falciform
fold from the peritoneum which extends from the liver to the diaphragm to the anterior abdominal wall, other small fold extend to the superior and posterior surfaces of the liver to diaphragm
round
hangs below the falciform ligament, below the liver and runs towards the umbilicus
coronary
attaches liver to diaphragm
triangular
attaches liver to the diaphragm laterally
portal fissure
region on the posterior surface where several structures enter and exit the gland, portal vein enters carrying blood from the stomach, spleen, pancreas, SI and LI
hepatic artery enters carrying arterial blood
branch from the coeliac artery which branches from the abdominal aorta
porta heaptis
lies on the inf surface between the quadrate anteriorly and caudate posteriorly
portal vein, hepatic artery and neves enter the L & R hepatic ducts , lymph vessels leave the liver
bile leaves to go to the GB via the hepatic ducts
where does the lymph drain into
abdominal and thoracic nodes
four lobes:
right
left
quadrate (subdivision of the right)
caudate (subdivision of the left)
anterior
filiform ligament separates left and right
teres ligament holds the round ligament
superior
upper portion
inferior
lower edge
visceral
slopes from the posterior border to the tip of the anterior border
peritoneum of the liver
enclosed by a thin fibrous capsule and is an retroperitoneal organ
folds of the peritoneum form ligaments which support and hold the liver in place, attaching to the inferior surface of the diaphragm
weight and size
1.4kg and 20cm long
where does it lie
below the diaphragm to the right and overlaps part of the stomach
what type of blood supply does it have
double
describe the arterial supply
heart -> aorta -> coeliac trunk -> common hepatic artery (25%)
nutrient rich venous blood is brought to the liver from the GI tract from the portal vein (75%)
venous supply
posterior surface into the IVC from the hepatic veins
where does anterior lymph drainage go
hepatic lymph nodes at the hilum -> coeliac nodes -> cisterns chyli -> thoracic duct
where does posterior lymph drainage go
drains into the phrenic and posterior mediastinal nodes -> right lymphatic and thoracic duct
describe the nerve supply in the parenchyma
innervated by the hepatic plexus containing
- sympathetic coeliac plexus
- parasympathetic vagus nerve
fibres enter at the portages hepatis and follow the path of the hepatic artery and portal vein
describe the structure of the lobules
many make up the lobes
composed of hepatocytes which are lined up in rows
columns of cuboidal epithelium which contain glycogen and fat
consist of sheets of hepatic cells which single layer hexagonal arrangements, these are stacked on each other, but are separated by sinusoids
small blood vessels diffuse oxygen and nutrients across into the capillaries
what is the role of the hepatocytes
remove substances and metabolise them
what is the central vein
it is found in the centre of the lobule which is the tributary for the hepatic vein
blood sinusoids
have a wider diameter than capillaries
lined with endothelial cells forming part of the recticoendothelial system
lined with knupffer cells which are specialised macrophages
what does the portal canal contain a branch of
hepatic artery
portal vein (deoxygenated blood from organs)
hepatic duct
describe the blood flow from the hepatic artery and portal vein
enters the blood sinusoids, passing between the cells to reach the central vein and back into the venous system.
blood drains from the sinusoids into the central vein which merges with veins from other lobules forming larger veins which form the hepatic vein which leave the liver into the IVC
what is the reticuloendothelial system
protective system
knuppfer cells ingest and destroy worn out blood cells and any foreign particles present in the blood.
phagocytosis (rate depends on the blood flow and cell function)
what do hepatocytes secrete
bile
bile canalicular
run between the columns of the hepatocytes, each column has a blood sinusoid on one side and a bile canniulus on the other
these join yo form large bile canals, forming the right and left hepatic ducts which drain bile from the liver which lies in the portal canal
what is found in each lobule
lymphoid tissue and a lymphatic network
what are the functions of the liver
heat production
bile production
storage of vitamin A and D
Fe storage
formation of plasma proteins
formation of antibodies
deamination of AA
transamination
storage of anti-anaemic factor
formation of prothrombin and fibrinogen
formation of heparin
carb metabolism
breakdown of erythrocytes and defence
bile production and excretion
inactivation of hormones
fat metabolism
detoxification of drugs and toxic substances
formation of plasma proteins
AA-> protein
absorbed in intestine
transamination
nitrogenous portion attaches to another carb forming a new molecule/ non essential AA
storage of anti-anaemic factor
vitamin 12 is absorbed from the stomach and stored until the liver needs it
iron storage
absorbed in the intestine
released by Hb breakdown
formation of prothrombin and fibrinogen
needed in blood clotting
heparin
prevents intravascular clotting in the body
formation of antibodies
recticoendothelial cells involved in the production
carb metabolism
maintain plasma glucose levels
when levels are high glucose is converted to glycogen for storage under the influence of insulin
when levels are low glucagon converts glycogen into glucose
bile production and excretion
hepatocytes synthesis the contents of bile from mixed arterial and venous blood in the sinusoids
inactivation of which hormones
cortisol
sex hormones
aldostrone
insulin
glucagon
thyroid
detoxification of drugs and toxic substances
ethanol, waste and microbial toxins are metabolised so once it leaves the liver it is at an inadequate level to achieve therapeutic effects
what colours faeces
stereobilin, small amounts are reabsorbed and excreted in the urone as urinobilinogen
what causes jaundice
excess of bilirubin
what is a product of Hb breakdown
bile pigments
what does bile facilitate
absorption of fatty acids, glycerol and fat soluble vitamins
what happens when the sphincter of Oddi is shut
bile accumulates, removal of water concentrates bile
where does bile flow
down from the hepatic ducts to the common bile duct
functions of bile
fat digestion: bile acid is synthesised by hepatocytes from cholesterol then secreted into bile as Na and K
bile salts make cholesterol and fatty acids more soluble
excretion of bilirubin: product of haemolysis of erthyrocytes by hepatic macrophages in the live
insoluble in water so it is blood bound to albumin
it is conjugates with glucronic acid, becoming water soluble so can be excreted in bile
enterohepatic circulation
large amount of bile salts water the SI from a small bile acid pool
what is bilirubin converted into
stereorubin
