W-7

W-7 has been reported to be a calmodulin (CaM) antagonist that inhibits Ca²⁺/calmodulin-regulated enzyme activities. Injection of murine tails with W-7 has demonstrated this agents ability to decrease tolerance to antinociceptive effects, therefore, CaM and its dependent pathways have demonstrated the capacity to play a role in antinociceptive agent tolerance processes. This cell permeable compound has been found to inhibit proliferation of hamster ovary K1 cells. W-7 has also been noted to bind troponin C in the presence of Ca²⁺ and inhibit striated muscle contractions.