Drugs Flashcards
1
Q
Amytal (Amobarbital)
A
- Reversible Inhibitor of Complex I (NADH Dehydrogenase)
- Blockade of ETC with Amytal has been shown to protect cardiac muscle during ischemia-reperfusion by limiting ROS production
○ Protective against ROS accumulation - Still will make some ATP via Complex II and BYPASS REACTIONS (via Succinate DH –> FADH2)
- Blockade of ETC with Amytal has been shown to protect cardiac muscle during ischemia-reperfusion by limiting ROS production
2
Q
Rotenone
A
- Inhibits Complex I (NADH Dehydrogenase)
- Naturally occurring pesticide
- Fish poison
3
Q
Antimycin
A
- Inhibits Complex III
○ Binds to cytochrome b in the reduced state –> stops ETC
○ Inhibits BOTH BYPASS AND NON-BYPASS REACTIONS (because it’s beyond complex II)
§ Complexes I, CoQ, + Complex II: fully reduced
§ Complexes III, Cytochrome C, + Complex IV: fully oxidized because no electron transport can occur here and beyond- Antifungal: agricultural use
4
Q
Cyanide
A
- Inhibits Complex IV
○ CN binds to oxidized form of Heme Iron (Ferric: Fe 3+) –> prevents Complex IV from being reduced!- Treatment for Cyanide Poisoning:
○ Nitrite (NO2-) followed by Thiosulfate (S2O3)
§ Nitrate: Hemoglobin + Nitrite –> Met-Hb (Fe3+) –> Met-Hb competes for binding of CN to Complex IV–> CN-Met-Hb (Fe3+)
§ Thiosulfate: Thiosulfate –> reacts with CN – SCN (Thiocyanate) + SO3 –> excreted urine
□ Thiocyanate is less toxic and more hydrophilic –> excreted in urine
○ Thiosulfate can also work on its own
§ Thiosulfate + CN –> via Rhodanese enzyme (endogenous) –> SCN (Thiocyanate) + SO3 –> Urine
- Treatment for Cyanide Poisoning:
5
Q
Oligomycin
A
- Inhibits Fo portion of ATP Synthase:
- Blocks proton flow through Fo –> prevents reentry of protons into mitochondrial matrix
- NO ATP MADE
- Proton gradient builds up
- Electron transport will soon stop because of the difficulty of pumping protons against a VERY steep proton gradient –> inhibition of ATP formation by Oligomycin also prevents oxidation reduction reactions
- Used in the lab
6
Q
AraC
A
cancer treatment
- Damage the inner mitochondrial membrane: dissipates proton flow so it goes back into matrix
7
Q
AZT
A
used as HIV treatment
- Damage the inner mitochondrial membrane: dissipates proton flow so it goes back into matrix
8
Q
Aspirin
A
- Kidnaps protons within intermembrane space –> cross inner membrane –> into matrix
○ Able to do this because it is very LIPID SOLUBLE and weak base
9
Q
DNP (Dinitrophenol) high dose
A
- Kidnaps protons within intermembrane space –> cross inner membrane –> into matrix
○ Able to do this because it is very LIPID SOLUBLE and weak base
10
Q
Atratyloside
A
- Inhibits ADP/ATP Antiporter (ATP/ADP Translocase)
- Prevents transport and availability of ADP in the matrix for ATP synthesis –> stops ATP synthesis
- Atractyloside Poisoning occurs in Mediterranean area and Northern Africa:
○ Atractylis gummifera L:
§ Easily confused with wild artichoke
§ Children eat because sweet tasting and roots like chewing gum
11
Q
Disulfarim
A
- Inhibits Acetaldehyde Dehydrogenase activity
- Causes unpleasant effects when even small amounts of alcohol are consumed
○ Unpleasant effects due to ↑acetaldehyde - Discourages drinking but not a cure for alcoholism
- Causes unpleasant effects when even small amounts of alcohol are consumed
12
Q
NAPQI (N-Acetylbenzoquinonemine)
A
- metabolite of Tylenol (Acetaminophen) by MEOS system
- chronic heavy drinks who are sober: CYP activity is enhanced. as a result, the metabolism of Tylenol is enhanced –> increase in NAPQI –> LIVER DAMAGE
13
Q
Phenytoin
A
- Inhibits Folate Conjugase (Expressed on jejunum epithelium)
- prevents conversion of polyglutamate folate –> monoglutamate folate
14
Q
Methotrexate
A
- COMPETITIVE INHIBITOR of DHFR
- prevents conversion of Folate –> DHF –> THF
- chemotherapeutic
15
Q
Aminopterin
A
- Inhibits DHFR
- prevents conversion of Folate –> DHF –> THF
- chemotherapeutic*