Vasodilators Flashcards
What channels do vasodilators affect?
K+ channel agonists
In vascular endothelium what activates nitric oxide synthase?
Ca2+-CAM
Important isoform we talked about in class of nitric oxide synthesis?
endothelial Nitric oxide synthase
Where is NOS?
Vascular endothelium
Where does NO diffuse to?
Vascular smooth muscle
Where is eNOS found?
Endothelial cells of the vasculature
Where is Guanylate Cyclase found?
Vascular smooth muscle
Effect of acetylcholine on smooth muscle?
Relaxes smooth muscle
What does Nitric oxide bind to in Guanylate Cyclase?
Heme iron prosthetic group
Protein kinase G relaxes smooth muscles by inhbiting which Ca2+ channel?
Cav1.2
Protein kinase G relaxes smooth muscles by stimulation of what?
Ca2+ activated K+ channels
A decreased MLC phosphorylation involves what enzyme?
Myosin phosphatase 1
Phospholamban has what effect in reference to protein kinase G?
Enhanced Ca2+ uptake in to ER
What breaks down Organic nitrates to nitric oxide?
Aldehyde dehydrogenase
What occurs with continuous administration of organic nitrates?
Tolerance
How and when do you give organic nitrates?
Give sublingually in treatment of acute attacks of angina
Tolerance to glyceryl Trinitrate is associated with who?
Munitions workere
Glu 504 is efficient at metabolizing what?
GTN
What accounts for the the lack of efficacy of GTN in large % of Asian population?
30-50% of Asians have one Lys 504 allele
Lys 504 allele also accounts for what?
Alcohol intolerance
Where is prostacyclin produced?
Endothelium
3 drugs used to treat pulmonary hypertension?
Prostacyclin
Treprostinil
lloprost
How do you administer Prostacyclin?
IV
How do you administer Treprostinil?
Oral
IV
How do you administer lloprost?
Inhalation
What does Hydralazine do?
Dilates arterioles preferentially
Mechanism of Hydralazine?
Interferes with release of Ca2+ from the ER
BiDil is known for treating what?
Decreases mortality in African Americans with CHF
What does Nitroprusside do?
Dilates veins and arterioles
What limits duration of treatment with nitroprusside
Metabolized in erythrocytes to NO radical, 4CN-, and cyanmethemoglobin
Riociguat has what effect on cGMP?
Increases cGMP concentration in VSM
Riociguat is a substrate for what?
P-gp, CYP1A1, 3A
Sildenafil is a potent and specific inhibitor of what?
cGMP PDE 5
PDE 5 is predominant where?
Corpus cavernosum
Benefits of Levitra?
Shorter time to onset than Viagra
More selective for PDE5 than Viagra
Benefits of Cialis? big dick marley says hello
More selective for PDE5 than Viagra
Longer duration of action than Viagra or Levitra
