The permeability of the membranes of experimental secondary cysts of Echinococcus granulosus to [14C]mebendazole

The permeability of secondary E. granulosus cysts to ¹⁴C]mebendazole was studied. The cysts were obtained by transplanting secondary cysts raised in mice into rats. The permeability to ¹⁴C]mebendazole was established by two different experiments: uptake and washout of the drug. The cyst wall permeability to ¹⁴C]mebendazole was found to be 1·33 × 10^?4 cm s^?1, which is of the same order as the diffusion permeability coefficient to water (1·88 × 10^?4 cm s^?1, Rotunno, Kammerer, Perez Esandi & Cereijido, 1974).The drug readily permeates through the cyst wall and experimental data suggest that it moves across the barrier by simple diffusion.