Background:

Milrinone is a selective inhibitor of phosphodiesterase 3 (PDE-3) with a IC50 value of 56±12nM [1]

Milrinone has been noted to inhibit both members of the PDE3 family, PDE3A, which is prominent in heart, vascular smooth muscle, and platelets, as well as PDE3B, which is prominent in fat, liver, and pancreatic islets. Milrinone has shown the effect of concentration-dependent inhibition of PDE3 on the photolabelling with a IC50 value of 56±12nM. In addition, Milrinone has been reported to increase the accumulation of [3H]cAMP with a EC50 value of 5329±970nM in platelets. Apart from these, Milrinone has been revealed to have positive inotropic and vasodilatiry activities and thus used in clinical practice for short-trem treatment of patients who have the acute decompensated heart failure [1, 2].

参考文献:
[1] Tang KM1, Jang EK, Haslam RJ. Photoaffinity labelling of cyclic GMP-inhibited phosphodiesterase (PDE III) in human and rat platelets and rat tissues: effects of phosphodiesterase inhibitors. Eur J Pharmacol. 1994 Jun 15;268(1):105-14.
[2] Cheung P1, Yang G, Boden G. Milrinone, a selective phosphodiesterase 3 inhibitor, stimulates lipolysis, endogenous glucose production, and insulin secretion. Metabolism. 2003 Nov;52(11):1496-500.