THE EFFECT OF TRICLABENDAZOLE (FASINEX) ON PROTEIN-SYNTHESIS BY THE LIVER FLUKE, FASCIOLA-HEPATICA

The effect of the active sulphoxide metabolite of the anthelmintic tri clabendazole (TCBZ-SX, 15-50 mu g ml(-1)) on the incorporation of radi oactively labelled [C-14] leucine by adult Fasciola hepatica tissue sl ices was measured by liquid scintillation counting. In addition, the a bility of the microfilament-disrupting drug, cytochalasin B, and the m icrotubule-disrupting drug, tubulozole-C, to inhibit protein synthesis , was assessed by similar methods and compared with TCBZ-SX. The estab lished protein synthesis inhibitors, cycloheximide and actinomycin D w ere used as positive controls. All the drugs showed a significant inhi bition of protein synthesis, albeit to different extents; however, TCB Z-SX was the most potent, with no significant difference between its e ffect and that of cycloheximide or actinomycin D. Moreover, the concen tration of TCBZ-SX, above 15 mu g ml(-1), had little further influence on incorporation of [C-14] leucine. This investigation demonstrates t he inhibitory effect of TCBZ-SX, cytochalasin B and tubulozole-C on pr otein synthesis in F. hepatica and confirms the qualitative observatio ns made in several previous ultrastructural studies.