What are prostanoids and leukotrienes synthesized from?
B. Arachidonic Acid
C. Free Fatty Acids
What is another name for Arachidonic acid?
A. Eicosatetraeonic Acid
C. Lipotechoic Acid
D. Linoleic Acid
Eicosa= means 20 as in 20 carbons
Tetra= means 4 as in a double bond at position 4
Aen= means double bonds
Based on the picture provided what enzyme is responsible for liberating Arachidonic acid from the membrane phospholipid?
B. Phospholipase A2
What source(s) can the body recieve Arachidonic acid from?
A. Dietary Arachidonic Acid
B. Synthesized from Linoleic Acid
C. A and B
D. None of the above
Which of these drug classes can inhibit Phospholipase A2 ?
What are the three enzymes that can metabolize Arachidonic Acid into products that the body will utilize? (Select All)
A. COX-1, COX-2
A, B, D
When Arachidonic Acid is metabolized by COX-type enzymes Prostanoids will be produced. Which of the following are prostanoids? (Select All)
A, C, F
HETEs are made from LOX enzymes
EETs are made from CYP450 enzymes
Leukotrienes are made from LOX enzymes
Based on the image provided which of the structures represents Linolenic Acid?
Omega-3 means on the omega carbon (the last carbon to the far right, the carbon furthest away from the carbonyl group) you count 3 carbons from the right and you land at 3. There is where you will find the first double bond. On the Omega-6 structure the 6th carbon from the last has the double bond and represents structure 1.
When COX enzymes metabolize Arachidonic acid it will produce prostanoids such as thromboxanes (TxA2). What is the function of thromboxane?
A. Anti-aggregation (hypotensive vasculature)
B. Protection of Stomach Lining
C. Pro-Aggregation (platelets)
When COX enzymes metabolize Arachidonic acid it will create Prostanoids such as PGE2. What is the function of PGE2?
A. Protection of Stomach Lining
B. Pro-Aggregation (Platelets)
C. Anti-Aggregation (Hypotensive vasculature)
When COX enzymes metabolize Arachidonic acid it produces prostanoids such as PGI2. What is the function of PGI2?
A. Pro-Aggregation (platelets)
B. Anti-Aggregation (Hypotensive vasculature)
C. Protection of Stomach Lining
What statements are true regarding COX-1 enzymes? (Select All)
A. It is a constituative enzyme (Expressed at all times)
B. Produces Prostacyclins from Arachidonic Acid
C. Expressed in mucosal lining and platelets
D. Produces Thromboxanes and Prostaglandins from Arachidonic Acid
E. It is an inducible enzyme that is expressed in response to inflammatory mediators
A, C, D
Which of the following statements are true regarding the COX-2 enzymes?
A. Inducible in response to inflammatory mediators
B. Expressed in vascular endothelial cells
C. Produces Thromboxanes from Arachidonic Acid
D. The enzyme is expressed constituitively (Always expressed)
E. Produces Prostacyclins (PGI2) which dilate vasculature
F. Produces Prostaglandins from Arachidonic Acid
A, B, E, F
The blue channels circled on both COX-1 (top-left) and COX-2 (bottom-right) enzymes are known as _____.
A. Hydrophobic Channel
B. Hydrophilic Channel
C. Lipid Channel
D. Enzyme Channel
It is known as a hydrophobic channel because all of the amino acids in that location have hydrophobic side-chains
What are the three amino acids located in these hydrophobic channels?
D. Aspartic Acid
A, B, E
Based on the structures of the COX-1 and COX-2 enzymes the _____ portion in Arachidonic Acid will bind to the hydrophobic channel. The ____ portion of the Arachidonic Acid will bind to the Arginine group (on the left of the enzyme).
A. 20-carbon chain, carboxylic acid
B. carboxylic acid, 20-carbon chain
When comparing the strcutrures of the COX enzymes they differ in their allosteric pocket. COX 1 has a ____ amino acid in it's allosteric pocket and COX-2 has a ___ enzyme in its allosteric pocket. How do these different amino acids affect the accessibility of the allosteric pocket for each enzyme?
A. Isoleucine (Ile), Valine (Val)
B. Valine (Val), Isoleucine (Ile)
The allosteric pocket in COX-1 will be closed since the isoleucine completely blocks it off. The allosteric pocket in COX-2 will be open since Valine is a very small amino acid in comparison to Isoleucine.
Which of the following statements regarding Acetaminophen are true?
A. The medication acts centrally
B. Also known as Paracetamol
C. Weakly acidic and insoluble in water
D. Can be formulated in solution with Propylene Glycol
E. All of the above
T/F Acetaminophen is one of the first medications used in the treatment of osteoarthritis for its analgesic properties.
The enzymes that normally metabolize Acetaminophen are (Blue) and (Green).
A. Glucuronidation, Sulfation
B. Sulfation, Glucuronidation
C. Methylation, Sulfation
D. Glucuronidaiton, Methylation
When medications have this particular p-Quinone or p-Benzoquinone in their structure what can be said about the medication?
A. Nothing notable
B. Pro-Antiinflammatory properites
C. This group causes Oxidative Damage
D. This group is unable to be metabolized by the body
Glucuronidation is the major pathway if acetaminophen in ____ and Sulfation is the major pathway of acetaminophen metabolism in _____.
A. Adults, Adults
B. Adults, Children
C. Children, Children
D. Children, Adults
The following picture shows the Minor metabolic pathway of Acetaminophen. What is the enzyme responsible for this metabolism?
E. Both B and C
It is metabolized by both 3A4 and 2E1 but MORE by 2E1
What is the name of the metabolite formed when Acetaminophen is metabolized by the CYP2E1 and 3A4 enzymes?
When NAPQI is created it can undergo metabolism in order to remove it safely from the body. What enzyme is responsible for this?
D. Glutathione (GSH)
The portion of this reaction shown in green takes place when someone has overdosed on Acetaminophen and large amounts of NAPQI have been produced. What antidote for APAP toxicity is being illustrated here?
C. N-Acetylcysteine (NAC)
In the metabolic pathway illustrated in red, NAPQI is being metabolized by ____ and creating a metabolite that is hepatotoxic.
A. Glutathione metabolites
B. Hepatic Proteins (Sulfhydril, SH)
C. Renal Proteins
D. Hepatic Lipases
What will happen when NAPQI is metabolized by Hepatic Proteins (SH) instead of GSH?
A. Hepato toxicity
B. Hepatic necrosis
C. Renal Failure
D. All of the above
The amino acid ____ in glutathione is responsible for it's ability to bind to APAP. The specific funcitonal goup in the amino acid that is is responsible for this is ___.
A. Valine, Sulfhydryl (SH)
B. Cysteine, Sulfhydryl (SH)
C. Cysteine, Carboxylic (COOH)
D. Methionine, Sulfhydryl (SH)
How does taking acetaminophen with alochol cause an increased chance of hepatic necrosis?
Alcohol induces the expression of CYP2E1 which is responsible for converting APAP to NAPQI. Increased amouts of NAPQI will cause your GSH reserves to be depleted. As a result NAPQI will undergo more metabolism by the hepatic SH proteins and cause hepatotoxicity. This is true even at lower doses of APAP.