Pharm 21 Vascular Tone Flashcards
MOA:
Donates NO–>activates guanylyl cyclase and increases dephosphorylation of myosin light chain in vascular smooth muscle= vasodilation
Nitrates, Inhaled NO, Sodium Nitroprusside
Tx: short acting (sublingual), long acting (oral) angina
Isosorbide dinitrate
Consideration:
venous dilation greater than arteriolar
isosorbide dinitrate
Organic Nitrates (5)
isosorbide dinitrate, isosorbide 5-mononitrate, nitroglycerin, sodium nitroprusside, inhaled NO gas
Tx:
prophylaxis angina, chronic IHD
isosorbide 5-mononitrate
consideration:
100% bioavailable orally
Isosorbide 5-mononitrate
Tx:
Agnina attacks, chronic IHD, acute heart failure
Nitroglycerin (NTG)
Consideration: Ergotamine may oppose coronary vasodilation of nitrates
NTG
Tx:
HTN emergency, severe cardiac failure, Ergot alkaloid toxicity
Sodium nitroprusside
Consideration: cyanide toxicity (thiocyanate toxicity)
sodium nitroprusside
Tx:
Neonatal respiratory failure
inhaled NO gas
Consideration:
selectively dilates pulmonary vasculature
inhaled NO gas
Phosphodiesterase Type V (PDE5) Inhibitors (3)
Sildenafil, Vardenafil, Tadalafil
MOA: Inhibit PDE5 (enzyme for converting cGMP to GMP) cGMP normally relaxes vessels= dilation (PDE5 inactivate cGMP-->GMP)
Phosphodiesterase Type 5 (PDE5) Inhibitors
Tx:
Erectile dysfunction
PDE5 inhibitors
consideration:
concomitant use of organic nitrate vasodilators= Hypotension
PDE5 inhibitors