Pharmacology Flashcards
Pramlintide
Amylin analog. MOA = decrease gastric emptying and decrease glucagon. Used for type 1 + type 2 DM.
Dopamine MOA
At low doses stimulates D1 receptors in the renal vasculature and tubules, thereby increasing GFR, RBF, and sodium excretion. Big heart in middle of room + normal sized christian is squeezing it/at high doses stimulates beta-1 adrenergic receptors in the heart, thereby increasing cardiac contractility + pulse pressure + systolic BP. Huge air force one plane by the left that monster Christian is driving/at highest doses stimulates alpha-1 receptors in the systemic vasculature.
Why do you give dopamine for shock?
To stimulate a1 receptors in the systemic vasculature, causing vasoconstriction.
Amiloride vs. amiodarone vs.
Amiloride –> K+ sparing diuretic.
amiodarone –> K channel blocker
amlodipine –> Ca channel blocker
Ergotamine
o Code: Elisabeth with Erik backpack/ergotamine. Smoking a huge blunt + walking out of air force one/MOA = partial agonist/antagonist activity at tryptaminergic + dopaminergic + alpha-adrenergic receptors. Feet and arms are gangrenous/SE’s = peripheral vascular ischemia + potentially gangrene.
o Location: /usually used for migraines.
How can morphine therapy lead to toxicity?
Morphine is metabolized to active metabolites that accumulate and can cause CNS depression.
Drugs contraindicated in CHF
Diltiazem and verapamil.
Hydralazine MOA
Smooth muscle relaxant and vasodilator in arteries and arterioles. Exact mechanism unclear.
Phenoxybenzamine MOA
Non-selective irreversible alpha blocker
labetalol MOA
Mixed alpha/beta adrenergic antagonist
What is Vmax proportional to?
Enzyme concentration
Relationship of Km to Vmax
Km is enzyme saturation at 1/2Vmax
competitive inhibitor vs. noncompetitive inhibitor
FA 236
What does a change in y-intercept on Lineweaver-Burk plot indicate?
Increased y-intercept = decreased Vmax since y-axis is the reciprocal of Vmax
What does x-intercept represent on lineweaver-Burk plot?
The further to the right (i.e. the closer to zero), the greater the Km and the lower the affinity since x-axis is reciprocal of negative Km.
What is slope on Lineweaver-Burk plot?
Km/Vmax
How do you differentiate competitive inhibitors from noncompetitive on Lineweaver-Burk plot?
Reversible competitive inhibitors cross each other competitively, whereas noncompetitive inhibitors do not.
Competitive inhibitors, reversible
1) resemble substrate?
2) overcome by increased saturation?
3) bind active site?
4) effect on Vmax?
5) effect on Km?
6) potency? efficacy?
1) Yes
2) Yes
3) Yes
4) Unchanged
5) Increased
6) Decreased potency
Competitive inhibitors, IRREVERSIBLE
1) resemble substrate?
2) overcome by increased saturation?
3) bind active site?
4) effect on Vmax?
5) effect on Km?
6) potency? efficacy?
1) Yes
2) No
3) Yes
4) Decreased
5) Unchanged
6) Decreased efficacy
NONcompetitive inhibitors
1) resemble substrate?
2) overcome by increased saturation?
3) bind active site?
4) effect on Vmax?
5) effect on Km?
6) potency? efficacy?
1) No
2) No
3) No
4) Decreased
5) Unchanged
6) Decreased efficacy
What is bioavailability?
Fraction of administered drug reaching systemic circulation unchanged
bioavailability of IV dose of drug
100%
Why is bioavailability usually less than 100%
Incomplete absorption + first pass metabolism
How do liver and kidney disease affect Vd?
Decreased protein binding leads to increased volume of distribution.