5. Pharmacodynamics I Flashcards
Secretion via exocrine glands, neurotransmitter release from neurons, and hormonal release are all effects caused by which GPCR’s second messenger cascade? (MG)
A. Gs
B. Gi
C. Gq
D. Gp
C. Gq
Phospholipase C activation via Gq results in IP3 formation which releases intracellular calcium from the ER. Intracellular calcium causes all of the effects listed in the vignettte
Gp isn’t a thing
In GPCR’s, there are 3 main subunit. Which subunit is a GTPase? (MG)
A. alpha
B. beta
C. gamma
D. delta
A. alpha - this subunit has GDP bound when understimulated. Upon further stimulated, the GDP is switched out for GTP. When the stimulus is removed, GTP is cleaved (GTPase activity) to go back to the “resting” GDP bound state
delta is not part of GPCR
A 23 year old man is diagnosed with restleg syndrome. His physicians prescribes him Benzodiazepines. How does this medication act?
A. Bind to voltage gated sodium channels blocking them
B. Is a B-antagonist
C. Binds to the receptor of a chloride ion channel helping the channel to open
D.Bind to voltage gated sodium channels helping the channel to open
E. Binds to the receptor of a chloride ion channel causing blockage
RFA
Ans. C Benzos work by binding to chloride ion channels enhancing the ability of GABA to open the channel causing hyperpolarized neurons
A. Would describe the action of local anesthetics, the blockage causes the prevention of action potentials preventing pain perception
B. B-antagonist would describe a drug such as Propranolol a medication used for hypertension
D & E are the inverse actions of local anesthetics and Benzos respectively
A 8 month old boy is brought to the hospital by his father and mother. The child has been vomiting and crying for several hours. The child history has been healthy except for this history. His parents note that he has began teething and has been chewing on anything that he can get his hands on, including his older brothers toy trains which are made in China. Which of the listed medication would be the most appropriate to give to this child?
A. Colestipol B. Ipratropium C. Dimecaprol D. Imatinib E. Pyrimidine Analog
RFA
Ans. C Dimercaprol- the child from the information given is most likely suffering from lead poisoning due to teething on his older brother lead painted toys. Dimercaprol is a drug that chelates heavy metals so hence would be the most appropriate. ( Non receptor mediated)
A. Colestipol- binds to bile acid in the intestinal lumen and prevents reabsorption it is used to treat hyperlipidemia ( Non receptor mediated)
B. Ipratropium- muscarinic antagonist used for asthma
D. Imatinib- is a tyrosine kinase inhibitor used for treatment of leukemia
E. Pyrimidine analogs- are incorporated into nucleic acids and alter their function it is used for cancer and antiviral chemotherapy( non receptor mediated)
A 25 y/o female presents to her oncologist for follow-up appointment for leukemia She has not been responding well to her current drug treatment. The oncologist decides to switch her medication to which of the following drugs and corresponding categories?
A. Imatinib- Cytokine Receptor/JAK B. Bethanechol- G-protein-linked C. Benzodiazepine- Ion Channel D. Imatinib-Tyrosine Kinase Receptor E. Pyrimidines- Cytokine Receptor/JAK
SZ
Ans. D. Imatinib- Tyrosine Kinase Receptor
The only anti-cancer drugs listed are Imatinib and Pyrimidines. However, pyrimidines do not involve the JAK receptors. They are structural analogs and alter the function of nucleic acids.
A 55 y/o male with history of obesity, DM presents to your office for dizziness and headache. You check is BP and find it to 179/80 Hgmm. You start him on propanolol. What is the mechanism of action for the drug?
A. Ion Channels B. G protein-linked Receptors C. Enzyme linked Receptors D. Nuclear Receptors E. Chelates heavy metals
SZ
Ans. B G protein-linked receptors
Beta antagonist which is a weak competitive antagonist of epinephrine, causes relaxation.
A. Ion channels- local anesthetic, Ach, cAMP, benzos
C. Enzyme Linked Receptors- Insulin, Imatinib, EGFR, prolactin, interferons, etc
D. Nuclear Receptors- Steroids, thyroid hormones, Vit D
E. Chelates heavy metals- Dimercaprol
