Hepatic Disease Flashcards
(76 cards)
The liver can be separated into two lobes: right and left. If considering the blood flow via the portal vein, the liver can rather be divided into four sectors (right posterior, right anterior, left medial and left lateral) and further subdivided into eight segments. True or False?
True
The liver has 4 major functions. What are they?
1) Energy metabolism and substrate interconversion
2) Protein synthesis
3) Solubilisation, transport and storage
4) Protection and clearance
The liver is a major intervenient in carbohydrate, lipid and protein synthesis, metabolism and interconversion. True or False?
True
An increase in glucose levels in the blood promotes liver to increase glucose consumption by:
- storing glucose in the liver as ____________
(through _______________) - promoting the synthesis of fatty acids and
______________ (through glycolysis to generate _______________).
glycogen; glycogenesis; cholesterol; acetyl-CoA
Fatty acids will be esterified to glycerol to form
________________, which are then assembled to very low-density lipoproteins (_________) for secretion and transport to ____________ for storage and other tissues for immediate use (as in muscles).
Cholesterol can be catabolised to _______ ________ and secreted to adipose tissues upon its binding to _________.
triglycerides; VLDL; adipocytes; bile acids; VLDL
An decrease in glucose levels in the blood promotes liver to increase glucose production by:
- _________________
- _________________ (proteins from the muscles)
- converting triglycerides stored in adipose tissues and hydrolysing them to ________ ________ _________, which will then be transported back to the liver and used to synthesise ______________ and _________ bodies. Ketone bodies will be used for energy production in the brain and muscles.
glycogenolysis; gluconeogenesis; free fatty acids; triglycerides; ketone
Dietary fat is absorbed at the small intestine and packed into _________________. Then, they will be hydrolysed by lipoprotein lipases, losing _______________ and forming chylomicrons remnants which will be uptake from the liver.
Triglycerides and cholesterol stored in adipose tissue or others, or found in the bloodstream can also return to the liver by endocytosis of VLDLs and high-density proteins (______ – also synthesised and secreted by the liver).
Fatty acids, triglycerides and cholesterol can also be synthesized “de novo” (80 % of cholesterol) in the liver. When there is an excess of glucose, the glycolysis take place to generate ____________, which then stimulates the production of fatty acids and triglycerides.
chylomicrons; triglycerides; HDL; acetyl-CoA
Once in the liver, fatty acids can be stored within lipid ____________ (triglyceride core with a phospholipidic monolayer containing some structural proteins around it) or can lead to the synthesis of ________________.
droplets; triglycerides
In the liver, the lipids can also undergo:
- _____________: when triglycerides are hydrolyzed into glycerol and fatty acids for energy storage.
- β-oxidation: it occurs in the ______________ and _______________, when fatty acids are oxidised to produce energy.
- Secretion to other tissues and bile: both triglycerides and cholesterol can be transported and secreted to other tissues by _________. Moreover, cholesterol can also be excreted in the ________.
mitochondria; peroxisomes; VLDL; bile
What are some proteins that are produced in the liver?
- Albumin
- Clotting factors
- Angiotensinogen
- Insulin-like growth factor I
- Apolipoproteins: they assemble into lipoproteins to transport lipids to and from several tissues by receptor-mediated endocytosis.
- Thyroid-hormone-binding globulin: allow the transport of thyroxine (T4) in a form that is not fully accessible to all the tissues, allowing to maintain T4 free concentration in equilibrium.
- Transferrin and ferritin: transferrin binds to free iron at normal pH, changing its normal conformation and making possible to bind to transferrin receptors in hepatocytes. Once internalized and at lower pH, the iron detaches from transferrin and binds to ferritin, which act as iron reservoirs.
Bile is produced by the liver. True or False?
True
Ordena os acontecimentos associados à circulação enterohepática.
A.The bile is excreted through the bile duct in the duodenum. Once in the duodenum, bile acids support the lipids solubilization, digestion and absorption.
B.The bile goes through the gastrointestinal tract.
C.The bile is produced and transported from hepatocytes to the biliary tract.
D.Once in the ileum, most bile acids reenter the portal blood flow and return to the liver.
C - A - B - D
Vitamin A is stored in lipid droplets that can be found in ______________.
lipocytes
Half of the __________ concentration found in the human body is stored in the liver.
folate
Some drugs and toxic substances that enter the liver via portal vein are _____________, being difficult to excrete. Thus, the liver present some ____________ able to catalyze metabolic reactions that make those substances more hydrophilic, helping their solubilisation and
excretion. An example is what happens to cholesterol and _____________.
hydrophobic; enzymes; bilirubin
Apart from protecting the organism against certain insoluble drugs and toxic substances, the liver also presents a crucial role on the _____________ metabolism.
The metabolism of ____________ and ______________ in the liver results in the production of ammonia which is toxic for the cells.
Thus, within the hepatocytes, ammonia is converted into ________, a much less toxic substance that is excreted by the kidneys through urine.
ammonia; proteins; aminoacids; urea
O cortisol pode criar resistência à _____________.
insulina
Na ausência de insulina, o corpo acha que está em ________, mesmo com glicose circulante.
A insulina normalmente inibe:
- _______________;
- _______________;
-________________;
Sem insulina, esses processos ficam desinibidos.
jejum; lipólise; cetogénese; gluconeogénese
Alanine transaminase (ALT) or glutamic-pyruvic transaminase (GPT) catalyzes the transfer of an amino group from L-_________ to alpha-_______________, forming L-glutamate and ____________.
Primarily found in the liver, with much lesser amounts in the _________, ________, and ___________.
Male: < 41 UI/L
Female: < 31 UI/L
alanine; ketoglutarate; kidneys; heart; muscle
Aspartate aminotransferase (AST) or glutamic-oxaloacetic transaminase (GOT) catalyses the conversion of _____________ and alpha-ketoglutarate to ______________ and glutamate.
Found in the liver, heart, muscles, pancreas, and kidneys.
Male: < 37 UI/L
Female < 31 UI/L
aspartate; oxaloacetate
Gamma-glutamyl transferase (γ-GT) plays a crucial role in the metabolism of _______________, an antioxidant important for cellular protection and detoxication with higher concentrations in the _________, kidneys and ___________.
Male: 8-61 UI/L
Female: 5-36 UI/L
Elevated levels of γ-GT in the bloodstream might indicate bile duct __________ or _____________, or other liver damage.
glutathione; liver; pancreas; blockage; constriction
Alkaline phosphatase (ALP) responsible for metabolising ___________ ____________ __________,
acting on the dephosphorylation of nucleotides, _____________ and ___________.
Highly concentrated in the liver and ________ and is found in lesser concentrations in the intestines and kidneys.
Male: 40-129 UI/L
Female: 35-104 UI/L
organic phosphate esters; proteins; alkaloids; bones
Bilirubin is produced by the degradation of _________________. It is released to the plasma and binds to ___________ in an unconjugated (or _________) form. Once in the liver, bilirubin will passively enter hepatocytes, where it will
conjugate to glucuronic acid through the action of UDP-glucuronyl transferase.
Once in the conjugated (or _________) form, it will be excreted in the ______ to the intestine.
Normal levels: total bilirubin 0.3-1.0 mg/dL and direct bilirubin 0.1-0.3 mg/dL
Elevated levels appear in case of hepatocellular injury, _____________, or bile duct obstruction.
hemoglobin; albumin; indirect; direct; bile; hemolysis
Apart from ALT (GPT), AST (GOT), y-GT, ALP and bilirubin, what are other hepatic markers?
- Albumin
- Total serum protein
- Lactate dehydrogenase (LDH)
- Prothrombin time (PT)
