Unit 1: Exam Review Overview Flashcards
What are the characteristics of Zone 1?
- High O₂ levels: Supports fatty acid oxidation, gluconeogenesis.
- Mitochondrial-rich hepatocytes: High O₂ allows for ATP production to fuel energy-demanding processes.
- Glutathione (GSH): Antioxidant to neutralize ROS.*
- Fatty Acid Oxidation: First line of defense, generates ATP.
- Gluconeogenesis: Makes glucose for energy.
- Ammonia to Urea: Detoxifies ammonia, makes it less toxic.
What are the characteristics of Zone 3?
- Low O₂: Least oxygen, high risk of ROS.
- Cytochrome P450 (CYP): Detoxifies, includes CYP2E1.
- CYP2E1: Breaks down EtOH (alcohol).
- More vulnerable: Detox leads to ROS and oxidative stress.
Explain the mechanism of blood and bile flow
Blood Flow:
Blood enters the lobule -> Portal Triad -> Sinusoids -> Central Vein -> Blood exits the lobule
Bile Flow:
Produced bile -> Exits via Portal Triad -> Gallbladder for storage
What sequence of events is being shown here? What would explain the darkening of the urine?
- Normal liver -> fatty liver -> liver fibrosis -> cirrohosis
- Bilirubin/Liver dysfunction
Describe Bilirubin Metabolism
- Hemoglobin breaks down into heme and biliverdin.
- Biliverdin becomes unconjugated bilirubin.
- Unconjugated bilirubin binds to albumin and goes to the liver.
- In the liver, bilirubin is conjugated (made water-soluble).
- Conjugated bilirubin is excreted in bile or urine.
Clinical Chemistry in Liver Failure
Elevated:
- Total Bilirubin (conjugated & unconjugated)
- AST (Aspartate Aminotransferase)
- ALT (Alanine Aminotransferase)
- Alkaline Phosphatase
Decreased:
- Total Protein
- Albumin
- Globulin
What is the mechanism of CCl₄-induced steatosis in the liver?
- Metabolized by CYP2E1 in the liver.
- This creates radicals, leading to lipid peroxidation.
- Lipid aldehyde formation occurs, forming biomolecule adducts.
- The damage leads to cell death.
- Historically used as a solvent, still used in industry.
What are Councilman bodies and ballooning degeneration, and what do they indicate in liver pathology?
- Toxin/Viral Hepatitis: Councilman bodies -> apoptotic bodies -> apoptosis
- Fatty liver disease, alcoholic liver disease, acute heptatitis: Ballooning -> necrosis
Increased cell number
Hyperplasia
Decreased cell size
Atrophy
Change in cell type due to chronic irritation
Metaplasia
Increased cell size and cellular compartments
Hypertrophy
Apoptosis vs Necrosis
Tissue Sample? Stained Structures?
- Adipose Tissue
- Hematoxylin: Nuceli
- Eosin: Cytoplasm
Tissue Sample? Stained Structures?
- Dense Regular Connective Tissue
- Hematoxylin: Fibroblast Nuceli
- Eosin: Collagen Fibers
Tissue Sample? Stained Structures?
- Dense Irregular Connective Tissue
- Hematoxylin: Fibroblast Nuceli
- Eosin: Collagen fibers
Tissue Sample? Stained Structures?
- Chondrocytes in Bone
- Hematoxylin: Nuceli of the chondrocytes
- Eosin: Cartilage extracellular matrix
Tissue Sample? Stained Structures?
- Muscle skeletal
- Hematoxylin: nuceli
- Eosin: muscle fibers, collagen fibers
Tissue Sample? Stained Structures?
Tissue Sample? Stained Structures?
- Muscle Smooth
- Hematoxylin: Nuceli
- Eosin: Muscle fibers
Explain this staining process
- Primary antibody binds to the antigen on the protein
- Secondary antibody binds to the primary antibody and carries a conjugated substrate
- The enzyme reacts with DAB, producing a brown precipitate
- This process shows the location of the protein of interest (protein assay)
