Succinic dehydrogenase activity in the cestode Hymenolepis nana

1. 1. TTC was used under aerobic and anaerobic conditions to demonstrate succinic dehydrogenase activity in the cestode, Hymenolepis nana. It was observed that there was not equal reduction of the dye in all proglottids comprising the strobila of an intact worm. Reduction was observed in proglottids which were punctured with a surgical needle. Methylene blue was also used to verify the presence of this dehydrogenase. Preliminary studies conducted qualitatively indicated that sodium malonate inhibited succinate oxidation and TTC reduction. 2. 2. Apparent individuality of proglottids of the same strobila was observed and discussed. It was suggested that there are permeability differences along the strobila and that there may be an active and selective absorption of carbohydrates by proglottids, possibly involving phosphorylation processes.