µM)and showed more than an additive in-

Heblich et al. (1997) reported a likely cytotoxic action from the presence of cinnamoyl-dihydroxynardol, a sesquiterpene ester, in a chloroform extract of feverfew. The sesquiterpene ester inhibited part of the voltagedependent potassium current in undifferentiated NG108-15 (mouse neuroblastoma × rat glioma hybrid) cells.