The Effect of Host Castration and Fasting on the Rate of Glycogenesis in Hymenolepis diminuta

Abstract

Both glucose- and pyruvate-fortified media supported glycogenesis. Castration of the rat host caused a decline in the rate of glycogen synthesis from both glucose and pyruvate. There were some indications that fasting the rat host for 24 hours prior to the experiment permitted a higher rate of glycogen synthesis from glucose. It is apparent that, as had been pointed out elsewhere, the rat tapeworm has not entirely lost the ancestral ability to regulate its internal physiological processes in response to environmental conditions. In addition, it seems probable that the broad effects of castration on the physiology of the rat tapeworm are produced through a secondary set of conditions arising in the body of the host and should not be attributed to any direct effect of the absence of the hormone on the parasite.