Effects of mebendazole, albendazole, and praziquantel on succinate dehydrogenase, fumarate reductase, and malate dehydrogenase in Echinococcus granulosus cysts harbored in mice.

Echinococcus granulosus cyst wall possess high biochemical activities of malate dehydrogenase (MD) and fumarate reductase (FR), but low activity of succinate dehydrogenase (SD), suggesting that the cyst wall may utilize a partial reverse tricarboxylic acid cycle. When infected mice were given intragastrically with mebendazole, 25-50 mg.kg-1.d-1, albendazole 300 mg.kg-1.d-1 or praziquantel 500 mg.kg-1.d-1 for 7-14 d, no apparent effects on SD and FR activities of the cyst wall were found, while the MD activity was suppressed by all the 3 drugs, the inhibition rates being 34.6-61.6%, 59.8%, and 50.6%, respectively. The results suggested that MD may not be an important target for the antihydatidosis drugs.