Dansylcadaverine eliminates calmodulin stimulation of phosphodiesterase

Dansylcadaverine, which structurally resembles the calmodulin antagonists W-7 and W-5, prevented the calmodulin dependent stimulation of 3':5'-cyclic nucleotide phosphodiesterase in vitro. Dansylcadaverine and trifluoperazine sensitized cells to Pseudomonas aeruginosa exotoxin A in apparently the same way, exept that 40 times higher concentrations of dansylcadaverine than of trifluoperazine was required.