Practice Section Q's Flashcards
Multi-drug resistant tumor cells often express the product of the MDR1 gene. What is this gene product and how does it confer drug resistance?
P-glycoprotein: ATP-dependent transmembrane pump that causes the efflux of a variety of substances, esp. hydrophobic compounds. Normally expressed in intestinal and renal tubular epithelium to remove toxins, as well as the BBB.
What sort of centrally-acting drug could be used to treat spasmodic torticollis resulting from anti-psychotic use? Examples?
M1 receptor antagonists such as benztropine or diphenhydramine.
What receptor protein is abnormal in AML M3 (t15;17)?
Retinoic acid receptor
What structural feature of elastin is primarily responsible for its elastic properties?
extensive desmosine cross-linking between lysine residues on different chains
What enzyme catalyzes the formation of desmosine cross-links on elastin?
lysyl hydroxylase
What substance accumulates in vascular smooth muscle cells when nitrates and phosphodiesterase inhibitors for erectile dysfunction (e.g. tadalafil) are used in combination?
cGMP
which is a 2nd msgr of NO and metabolized by phosphodiesterase
What are the alpha-blockers?
“-zosins”: Doxazosin, Prazosin, and Terazosin
What are the 2 main indicatios for α-blocker therapy?
htn and BPH
What kind of drugs are metoprolol and atenolol?
cardioselective β-blockers (β1)
What drug is the first-line medication for both essential htn and osteoporosis, as well as isolated systolic htn?
hydrochlorothiazide
What is the mech of nitrates in angina tx?
venodilation –> decreased preload
Mech of carbamazapine.
binds to voltage-gated Na+ channels in the inactivated state.
What household drug is protective against progression to colon carcinoma and why?
Aspirin: COX-2 is expressed by most colon carcinomas and is thought to drive cell growth.
