GTN Spray

• How does cGMP cause vasodilation?

  cGMP causes protein kinase-dependent phosphorylation & activates downstream cascades -> promotes relaxation in vessels & cardiac tissue -> increased blood flow
• What is GTN?

  Glyceryl Trinitrate
• What is glyceryl trinitrate?

  Nitrate vasodilator
• What is the pharmacology of GTN?

  Converted into NO

  Activity: same as NO
• What is the indication of GTN?

  Angina (given sublingually, as a spray)
• What is the dosage of GTN spray?

  1-2 sprays

  After 5 mins, can have a 2nd dose (another 1-2 sprays)

  No more than 2 doses, after need to seek medical treatment
• What are the side effects of GTN?

  Hypotension

  Nausea

  Vomiting
• MOA - GTN

  GTN converted into NO in smooth muscle (by mitchondria aldehyde dehydrogenase) -> NO activates guanylate cyclase -> conversion of GTP to cGMP -> increased cGMP

  cGMP is an endogenous vasodilator
• Why is GTN delivered as a spray?

  Rapid absorption through buccal and sublingual mucosa

  Spray under tongue