Misc Sweatman Pharm Flashcards
Did these quickly as I studied, sorry if some are bizzarre half-thoughts
Effects of beta-1 and -2 receptor activation?
accelerates SA node, increases contractility, accelerates ectopic pacemakers IN HEART
Effects of alpha-1 receptor activation?
contract vessels by increasing DAG and IP3, which results in an increase of Ca++
What receptors act via NE?
alpha 1, alpha 2, beta 1
What receptors act via epi?
alpha 1, alpha 2, beta 1, beta 2
What receptor would you block to treat BPH?
alpha 1
What class of drugs cause 1st dose orthostatic hypotension? What specific drug is the most prominent?
alpha blockers
prazosin
Effects of alpha 2 receptors?
decrease cAMP production, which blocks further release of NE (feedback inhibition)
Effects of alpha-1 antagonists?
antagonist circulating NE and epi, which prevents vasoconstriction
Effects of alpha-2 antagonists?
block feedback inhibition, which increases NE release
increases CO, “tempering” BP lowering
Treatment for pheochromocytoma?
phenoxybenzamine
phentolamine
(alpha blocker)
Why does phenoxybenzamine cause nasal congestion and drowsiness?
minor action = blocking histamine, serotonin and ACh
What treats hypertensive emergency?
phentolamine
What is the difference between a small versus a large dose of alpha 2 antagonist?
small: increases BP
large: decrease BP (due to periph vasodil)
What limits the use of phentolamine in essential HTN?
postural hypotension, reflex tach ppt arrhythmias
Epi causes (increased/decreased) BP); treatment with an alpha blocker will.... Treatment with a beta blocker will...
increased BP
decrease BP
no effect
NE causes (increased/decreased) BP; treatment with an alpha blocker will.... Treatment with a beta blocker will...
increased BP
slight decrease in BP
no effect
What drug class affects renin release?
B1 agonists (on JG cells)
Intrinsic sympathomimetic activity?
pure: propranolol
partial:
pindolol
Drugs with membrane stabilizing ability?
propranolol
cervedilol
class 1 antiarrhythmics
How do drugs stabilize membranes?
bind/block fast Na channels which are responsible for rapid depol (decrease phase 0 slope)
What is intrinsic sympathomimetic activity?
activate receptors in the absence of catecholamines
What is inverse sympathomimetic activity?
selectively bind to inactive form of receptor and behave like competitive antagonists (“off”)
B antagonists that block Ca entry:
What does this do?
carvedilol
betaxolol
prevents contraction
B antagonist that produces NO:
nebivolol
B antagonists that are also a-1 R antagonists?
carvedilol
labetolol
B antagonist that has antioxidant activity?
carvedilol
What results from long term administration of beta blockers?
drop in peripheral vasc resistance
Beta blocker with no effect on renin? Most effective if elevated renin?
pindolol
propranolol
What effect does lipid solubility have on antihypertensives?
drugs that do NOT penetrate BBB (low sol) are effective anti-HTN
Who should NOT take beta blockers?
patients with:
- compensated HF, acute MI, cardiomeg
- AV conduction defects, as these drugs cause bradycardia
- bronchospastic disease (due to bronchoconstriction via beta-2)
Beta blockers should not be stopped abruptly because:
they can exacerbate angina and increase risk of sudden death (receptors are upregulated)
Lipophilic beta blockers may cause:
CNS depression, causing mental disorders, fatigue, vivid dreams
How do beta blockers affect plasma lipids?
increase triglycerides
decrease HDL
What type of beta blockers reduce cholesterol and LDL?
those with intrinsic sympathomimetic activity and cardioselectivity
Activation of what receptors mediates lipolysis?
alpha1
beta 1, 2, 3
What is the effect of using beta blockers post MI?
improved mortality
Non-CV uses for beta blockers?
tremor thyrotoxicosis anxiety migraines prevent bleeding from esoph varices glaucoma
Effects of ganglionic blockade on arterioles?
vasodilation
hypotension
Effects of ganglionic blockade on veins?
dilation/pooling
decreased venous return/CO
Effects of ganglionic blockade on heart?
tachycardia
Nicotinic receptors are ______ channels which mediate
post-synaptic ligand gated ion initial EPSP (caused by Na/K)
MOA of trimethaphan:
competes with ACh for ganglionic receptor binding
Causes dry mouth, vision problems, urinary retention, constipation?
ganglionic blockers
MOA of reserpine:
binds to NT storage vesicles and inhibits vesicle transporter VMAT2
=no storage/concentration of dopamine and NE
MOA of clonidine:
withdrawal of SNS tone resulting in decreased BP and decreased PVR
High, chronic overstimulation of alpha-2 recepors results in:
downregulation via beta-arr mediated endocytosis
i.e. during HF
Effects of alpha-2-autoreceptors
bradycardia
hypotension
Activation of central alpha-2-heteroreceptors
sedation hypothermia analgesia bradycardia* hypotension*
*due to vagal activation
Activation of peripheral, vascular alpha 2 receptors causes
vasoconstriction
Effects of central alpha 2 receptor agonists: (4)
decrease plasma renin activity
regression of LV hypertrophy
decreased PVR
decreased BP
Side effect of central alpha 2 receptor agonists:
salt/water retention (*trx duiretics, too)
Chelated by concurrent iron
methyldopa
Should be given with caution to diabetics
beta blockers
mask warning tachycardia (1) cause hypoglycemia (2)
Helpful in blocking reflex tachycardia
clonidine (alpha 2 agonists)
Adverse effects of central acting alpha 2 agonists
somnolence
dry mouth
Used to treat HTN in pregnancy?
*methyldopa
*labetalol (IV for HTN emergencies)
pindolol/propranolol
HCTZ (recently decided it was ok)
Do not give in pregnancy:
ACEI
ARBs
reserpine
Reserpine’s effects:
central and peripheral anti-HTN
Side effects of reserpine
psychotic depression (suicide)
CNS (sedation, inability to concentrate)
Exacerbation of PUD ulcerative colitis
Why are old centrally acting drugs good modern options?
cheap
better adverse effect profile
alpha blockers end in:
beta blockers end in:
ACEI end in:
ARBs end in:
- in/-ine
- olol
- pril
- artan
Treat v-tach:
- amiodarone
- lidocaine
- procainamide
MOA of class 1 antiarrhythmics:
na channel blocker
MOA of class 2 antiarrhythmics:
beta blocker
MOA of class 3 antiarrhythmics:
K channel blocker
MOA of class 4 antiarrhythmics:
Ca channel blocker
Effects of local epi?
vasoconstriction
Direct acting adrenergic agonists stimulate:
post-syn receptors
Indirect acting adrenergic agonists increase:
NE and epi availability
Cocaine is a (direct/indirect) adrenergic agonist
indirect (blocks reuptake of NE)
MAOI’s are (direct/indirect) adrenergic agonists
indirect (blocks metabolism of enzymes)
Treatment with reserpine results in a loss of (direct/indirect) adrenergic agonist action
indirect
Epi will ______ CO, _____ HR, ___ contracility and _____BP.
increase, increase, increase, increase
NE will ____HR, _____CO, ____BP, ____TPR, ____SV
no effect (due to vagus) no effect/decrease increase increase increase
Increases SBP more than DBP; why?
Epi
B-2 mediated increase in peripheral resistance
Epi causes more vaso-(dilation/constriction); why?
dilation
more effect on beta-2 than alpha receptors
Where does epi cause vasoconstriction?
skin, kidney, veins
Small doses of epi may cause:
decreased BP (due to differential receptor sensitivity)
Where are beta-1 receptors?
myocardium, PM, conducting tissues
How does epi affect the heart? (4)
shortened systole, increased HR, increased CO, increased O2 consumption
What is a possible side effect that epi may have on the heart?
PVC’s
How does epi affect the kidneys?
decreased renal bf by increasing vasc resistance
this will NOT change GFR and will decrease Na/K/CL excretion
How does epi affect renin levels?
increase due to beta-1 receptors in JGA
Can restore cardiac rhythm in patients with cardiac arrest
epi
What should be monitored in patients given NE?
BP
How do you measure dopamine’s effects?
urine
Dopamine acutely benefits patients with:
CHF
Renal failure
What receptors are activated by dopamine (in order of concentration)?
D1 > beta 1 > alpha 1
Effects of low dose dopamine?
renal, coronary, etc vasodilation
improves GFR
Effects of moderate dose dopamine?
vasodilation
increased CO
Effects of high dose dopamine?
increase PVR
renal vasoconstriction
Dobutamine will ____HR, ____SV, ____ contractility and ___CO
no effect
increase
increase
increase
Dobutamine is used to treat:
post cardiac surgery
after MI
CHF
How does isoproterenol affect BP?
decreases DBP (by decreasing PVR)
Phenylepherine has a stronger effect on (alpha/beta)
alpha
no beta!
Effects of phenylepherine:
increase BP
REFLEX decrease in HR and CO
Side effects of phenylepherine:
anxiety
hallucinations/psychosis
HTN
insomnia
Ephedrine affects what receptors?
alpha and beta
Effects of ephedrine:
increase HR
increase CO
increase BP
Side effects of ephedrine:
increases cardiac workload > angina ventricular dysfunction palpitations s-tach arrhythmia (*v-fib)
the parasympathetic nervous system = ______ receptors
muscarinic
M2 receptor activation leads to…
reduced contractility
SA node deceleration - decreased HR
M3 receptor activation leads to…
NO synthesis
Effects of ACh on CV system:
vasodilation
decreased HR
decreased AV node conduction
decreased force of atrial contraction
Effects of M2 on cell channels?
activate K
inhibit Ca
IV ACh results in…
What is a possible negative effect?
transient decrease in BP
reflex tachy
bradycardia or AV node conduction block
Effects of atropine
increase resting HR (no effect or maximal HR)
counteracts vasodilation + BP drop
What is an indirect action of atropine?
vasodilation of cutaneous vessels (atropine flush)
*this offsets the heat-loss reduction caused by sweating inhibition
Prevents cardiac arrest from vagal stimulation
atropine
How does atropine benefit patients with MI’s?
(if inferior or posterior wall)
relieves severe bradycardia or AV block
Dobutamine is a:
beta agonist with both alpha1 agonist and antagonist activity (cancels out!)