Term
Where in the body are reductases found? |
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Definition
ER, cytosol, anaerobic gut microorganisms |
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Term
What are the different types of reduction reactions? |
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Definition
azoreduction, nitroreduction, ketoreduction |
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Term
Where do hydrolysis reactions take place? |
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Definition
plasma, liver, kidney, and all tissues |
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Term
What types of enzymes catalyze hydrolysis reactions? |
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Definition
esterase, amidase, and epoxide hydrolase |
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Term
What is succinylcholine apnea? |
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Definition
dut to an esterase deficiency, enzyme appears to have an altered affinity for esters, affects about 1/3000 |
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Term
Where is epoxide hydrolase found? |
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Definition
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Term
What are the two forms of epoxide hydrolase? |
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Definition
microsomal and soluble forms |
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Term
What induces epoxide hydrolase? |
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Definition
phenobarbital and 3 methylcholanthrene |
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Term
What induces epoxide hydrolase? |
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Definition
phenobarbital and 3 methylcholanthrene |
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Term
What types of reactions happen in phase 2 conjugation reactions? |
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Definition
glucouronidation, sulfate conjugation, acetylation, glutathione conjugation, methylation, glycine conjugation |
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Term
What enzyme is used for glucuronide conjugation? |
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Definition
UDP-glucuronyl-transferase |
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Term
What enzyme is used for sulfate conjugation? |
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Definition
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Term
What enzyme and substrate are used for acetylation? |
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Definition
acetyl CoA, N-acetyltransferase |
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Term
What enzyme is used for glutathione conjugation? |
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Definition
glutathione S transferase |
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Term
What enzymes perform methylation? |
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Definition
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Term
Where are methyltransferases located within the cell? |
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Definition
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Term
What activated molecule is used for methylation? |
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Definition
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Term
Which amino acid is most often used in conjugation reactions? |
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Definition
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Term
Where in the cell does amino acid conjugation occur? |
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Definition
mitochondria and cytoplasm |
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Term
What factors of an organism will affect drug metabolism? |
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Definition
genetics, aging, species differences |
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Term
Why do the elderly have a lower drug clearance? |
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Definition
decreased absorption, altered distribution, decreased metabolism, decreased excretion |
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Term
What is the equation for the rate of elimination? |
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Definition
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Term
What value is equal to the slope of the line plotted on a log [drug] over time? |
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Definition
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Term
What functional groups does glucuronidation react with? |
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Definition
hydroxyl, amine, or carboxylic acid |
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Term
Where in the cell does glucuronidation occur? |
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Definition
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Term
What fuctional groups does sulfate conjugation occur with? |
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Definition
alcohols, phenols, and aromatic amines |
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Term
Where does sulfate conjugation occur? |
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Definition
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Term
Where does acetylation occur? |
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Definition
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Term
Name 2 conjugation reactions that are saturable. |
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Definition
sulfate and glycine conjugation |
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Term
What functional groups does acetylation occur with? |
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Definition
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Term
Are most people in the US slow or fast acetylators? |
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Definition
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Term
What racial groups are rapid acetylators? slow acetylators? |
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Definition
japanese are rapid acetylators middle eastern, scandanavians, finns are slow |
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Term
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Definition
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Term
Slow acetylators are at risk for: |
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Definition
isoniazid-induced neurotoxicity, drug-induced SLE, and arylamine induced bladder cancer |
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Term
Fast acetylators are at risk for: |
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Definition
isoniazid induced hepatitis, and colorectal cancer (esp with rapid CYP1A2 type) |
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Term
What functional groups react in methylation reactions? |
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Definition
hydroxyl, sulfhydryl, and amine |
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Term
Where do glutathione conjugation reactions take place? |
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Definition
cytosol and mitochondria of liver and numerous other tissues |
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Term
Describe the structure of glutathione conjugation enzymes: |
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Definition
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Term
What type of conjugation reactions can ultimately form mercapturic acids? |
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Definition
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Term
What types of functional groups participate in glutathione conjugations? |
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Definition
aromatic hydrocarbons (epoxides), arylamines, organic halides, phenols, and ligand binidng cpabilities (ligandins) |
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Term
How do you induce alpha class GSTs? |
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Definition
ingestion of high levels of brussel sprouts |
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Term
What are the polymorphisms of glutathione conjugation? |
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Definition
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|
Term
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Definition
polymorphic (*0, 8a, and *b); null gene (increased risk of cancer), essentially absent in 20-50% of all individuals |
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Term
How many variants of GSTP1 are there? |
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Definition
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Term
GSTM1 null phenotype is linked to what cancers? |
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Definition
pituitary adenomas, head and neck cancer, malignant melanoma, colorectal cancer, and bladder carcinoma |
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Term
Is GSTM1 null phenotype associated with lung cancer? |
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Definition
yes but only in heavy smokers |
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Term
What functional groups participate in glycine conjugation? |
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Definition
aliphatic acids and aromatic carboxylic acids |
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Term
Name a type of conjugation reaction that is developmentally induced |
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Definition
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Term
What effect do ethanol and cimantidine have on drug metabolism |
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Definition
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Term
Name drugs that induce P450 and other drug metabolizing enzymes. |
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Definition
phenobarbital and other drugs, polycyclic hydrocarbons and carcinogenesis |
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Term
What dietary elements can affect drug metabolism? |
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Definition
charcoal broiled beef, vitamin deficiencies, brussel sprouts, grapefruit |
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Term
What is the relationship between the half life and the elimination constant? |
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Definition
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Term
What is the volume of distribution? |
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Definition
apparent volume into which a drug distributes in the body |
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Term
How do you calculate a volume of distribution? |
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Definition
inject a known quantity of drug as an IV bolus. take blood samples at various times after injection. Plot data on a semilogarithmic plot and extrapolate back to t=0 to calculate the concentration prior to elimination. VD= amount of drug/plasma concentration = X0/Cp |
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Term
List three equations that equal total clearance. |
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Definition
ClT = Kel * VD CLT = X0/area under the curve CLT = Cl(liver) + CL(kidney) + Cl(other) |
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Term
Describe an equation for rate of absorption. |
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Definition
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Term
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Definition
area under the curve of drug [] over time |
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Term
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Definition
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Term
How do you calculate teh total clearance of a drug administered IV. |
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Definition
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Term
How do you calculate total clearance in a drug that is administered extravascularly? |
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Definition
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Term
What is the extraction ratio for hepatic clearance? |
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Definition
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Term
What is the hepatic clearance for first order drugs? |
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Definition
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Term
What is the hepatic clearance for zero order drugs? |
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Definition
ClH = Fu * Cl(int), where Cl(int) = Vmax/Km |
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Term
Renal clearance is related to the rates of... |
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Definition
glomerular filtration, passive reabsorption, and active secretion |
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Term
Which type of drug reaches a steady state faster, those with a long half life or those with a short half life? |
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Definition
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Term
If renal clearance is greater than GFR, the the drug is being excreted by... |
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Definition
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Term
If renal clearance is less than GFR then several mechanisms may be responsible such as... |
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Definition
protein binding, tubular reabsorption, depressed GFR |
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Term
T/F The area under the curve for a drug given IV is greater than the area under the curve of the same drug given extravenously. |
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Definition
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Term
What is the equation for continuous IV infusion |
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Definition
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Term
The inital dose of a medicine which is greater than the following doses is termed a ________. |
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Definition
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