Phorbol 12,13-dibutyrate (Phorbol dibutyrate) is a PKC activator that inhibits α1-adrenoceptor-mediated positive inotropic effects in a concentration-dependent manner, induced by contraction of isolated rabbit vascular smooth muscle.

Selective cell-permeable peptide inhibitor of protein kinase C (IC50 ~ 0.5 μM). Consists of amino acids 19 - 31 of PKC pseudosubstrate domain linked by a disulphide bridge to a cell permeabilisation Antennapedia domain vector peptide. The Antennapedia peptide is actively taken up by intact cells, at 4 or 37°C, ensuring rapid and effective uptake of the inhibitor peptide. Once inside the cell, the disulphide bonds are subjected to reduction in the cytoplasm leading to release of the inhibitor peptide.

Miltefosine is used for the treatment of visceral and cutaneous leishmaniasis, and is undergoing clinical trials for this use in several other countries.