The drugs milrinone and dobutamine increase cAMP (cyclic adenosine monophosphate).
cAMP-Elevating Drugs
Several drugs can elevate cAMP levels, influencing various physiological processes. In the context of acute heart failure, cAMP-elevating drugs are particularly valuable.
Examples of cAMP-Elevating Drugs
The following examples illustrate how certain drugs increase cAMP:
- Milrinone: This drug inhibits phosphodiesterase-3 (PDE-3). PDE-3 normally breaks down cAMP, so inhibiting it leads to an increase in cAMP levels within cells.
- Dobutamine: This drug acts as a beta-adrenergic agonist. It stimulates beta-adrenergic receptors, which in turn activate adenylyl cyclase, an enzyme that produces cAMP.
Mechanism and Effect
Both milrinone and dobutamine enhance cardiac function by increasing cAMP. Elevated cAMP levels lead to:
- Increased intracellular calcium: Which enhances contractility.
- Vasodilation: Resulting in reduced afterload.
| Drug | Mechanism | Effect |
|---|---|---|
| Milrinone | PDE-3 inhibition | Increased cAMP, enhanced contractility |
| Dobutamine | Beta-adrenergic agonist (β1, β2, α1 agonist) | Increased cAMP, enhanced contractility and HR |
These drugs are used in acute heart failure treatment to improve heart function.
