TJ Guide 3 Flashcards
What is the dose limiting factor in microtubule inhibiting drugs?
Peripheral neuropathy, can be permanent
What is an example of a folate antagonist?
methotrexate
Note: This drug is needed in very high concentrations to inhibit tetrahydrofolate production
Antimetabolites terminate DNA production by impersonating real nucleotides. What other enzymes might be inhibited by these antimetabolites and when is this drug most cytotoxic?
RNA reductase
DNA polymerase
DNA ligase
DNA exonuclease
S-phase
How does p53 work?
- Induces p21 (CDK inhibitor) which keeps cell in G-phase
2. Causes cell death
What is deleted in cancer that causes degration of p53?
p19/ARF is deleted which in a normal cells keeps MDM2 from degrading p53
What is the idea behind alkylating agents?
cause so much crosslinking damage to DNA that that repair systems cant keep up and it can’t conform to the normal structure, preventing RNA synthesis and leading to eventual cell death
How do HDAC inhibitors act as anticancer drugs?
They inhibit HDAC which puts acetyl groups on lysine which reduces the +/- attraction of histones to DNA. Loosening of DNA leads to increased transcription. THE MAIN IDEA IS THAT THINGS LIKE P53 WILL GET ACTIVATED AGAIN SO THEY CAN PROGRAM CELL DEATH
Why do physicians usually do a CBC before giving chemo drugs?
myelosuppression is usually the dose limiting factor and they want to make sure patients have enough immune cells
T or F: Both topoisomerase inhibitors and antimetabolites are cell cycle specific
False, topoisomerases are independent of cell cycle
What steps are involved in synaptic signal transmission?
- Ca2+ channels open in response to AP
- Ca2+ triggers synapsin kinase to phosphorylate synapsin I
- Synapsin I triggers the vesicle to bind to the presynaptic terminal
- Receptors get signal and non-voltage gated Na+/K+ channels open and a graded depolariztion occurs
- If strong enough an AP is triggered
In the event that a neurotransmitter opens a K+ channel will it cause an IPSP or an EPSP?
IPSP - K+ will rush out down its concentration gradient
What channel is likely triggered in an EPSP?
a non-specific Na+/K+ channel
What two neurotransmitters commonly cause IPSPs?
glycine and GABA
What is the result of too many or too few D2 receptors?
Too much D2 = schizophrenia
Too little D2 = parkinsons
What type of cholinergic receptor leads to IPSPs in the heart?
muscarinic
What are the types of transmitter used at amino acid synapses?
GABA, Glycine –> typically IPSPs
Glutamate, aspartate —> typically EPSPs
angiotensin, Substance P, and oxytocin are examples of…
Neuroactive Peptides
What is thymosin?
prevents assembly of actin monomers into actin filaments
What is profilin?
promotes assembly of actin monomers into filaments?
What are formins?
drives the elongation of actin filaments at the plus end of the microfilament
Where is bundling protein found?
Filopodia
What is the major motor protein for actin?
myosins
What is tropmyosin?
side-binding protein that regulates myosin-dependent force generation
What is Gelsolin?
actin severing protein that converts actin gel into a more fluid state
