The Effect of Progesterone on Molting of Syphacia obvelata

The effect of ecdysteroids, the steroid hormones of insects (which happen to be the host of nematodes in many cases), on molting of nematodes is long accepted. Mammalian steroid hormones have been shown to affect the labor of nematodes in hosts. In order to examine whether mammalian steroid hormones can have a similar effect on the molting of nematodes, progesterone was applied to female mice infected with Syphacia obvelata. The worms were extracted from the mice in different time intervals and compared morphologically. No significant difference was observed among the different developmental stages of the worms, suggesting that progesterone does not have such an effect on molting of Syphacia obvelata. We suggest dissimilarities in molecular pathways have been the main reason for the observed differences between the effects of progesterone and ecdysteroids.