Plerocercoid growth

Table 8.8. Spirometra mansonoides comparison of the activities of the plerocercoid growth factor (PGF) to those associated with mammalian growth hormone (GH). (Data from Phares, 1987 ...

Hirai, K., Nishida, H., Shiwaku, K. Okuda, H. (1978). Studies on the plerocercoid growth factor of Spirometra erinacei (Rudolphi, 1819) with special reference to the effect on lipid mobilization in vitro. Japanese Journal of Parasitology, 27 527-33. 

Plerocercoid growth factor a homologue of human growth hormone. Parasitology Today, 3 346-9. 

Fig. 2.12. Scolex of Diphyllobothrium dendriticum plerocercoid. The neural elements have been labelled with growth hormone releasing factor (GRF), a vertebrate neuropeptide. In the main nerve cord (n) one GRF-immunoreactive cell body can be seen (large arrow) in the peripheral nervous system (P) several GRF-immunoreactive cells bodies occur (large arrows). The small arrows point to nerve terminals beneath the basal lamina of the tegument along the inner border of the bothridia. Sections stained with Stemberger s immunoperoxidase-antiperoxidase (PAP) technique. (Courtesy Dr Margaretha K. S. GustafFson.)...

Although there are few data available on the establishment or growth rate of plerocercoids in intermediate hosts, the morphology, ultrastructure, cytology and host-parasite relationships of the commonly available species have been studied extensively. The biochemistry is discussed in Chapter 4. 

Fig. 8.13. Growth of plerocercoids ( spargana ) of Spirometra erinacei in mature mice and their effect on the body weight of their hosts. (After Shiwaku et at., 1982.)...

Unlike Schistocephalus and Ligula, the majority of pseudophyllidean plerocercoids are morphologically undifferentiated, and must undergo considerable growth and differentiation before sexual maturity can be achieved. 

Phares, C. K. (1984). A method for the solubilization of a human growth hormone analogue for plerocercoids of Spirometra mansonoides. Journal of Parasitology, 70 840-2. 

Shiwaku, K., Hirai, K., Torii, M. Tsuboi, T. (1983). Effects of Spirometra erinacei plerocercoids on the growth of Snell dwarf mice. Parasitology, 87 447-53. 

Steelman, S. L., Glitzer, M. S., Ostlind, D. A. Mueller, J. F. (1971). Biological properties of the growth hormone-like factor from the plerocercoid of Spirometra mansonoides. Recent Progress in Hormone Research, 27 97-120. 

---