Origin and characteristics of glycogen cells in the developing murine placenta
Article first published online: 12 OCT 2006
Copyright © 2006 Wiley-Liss, Inc.
Volume 235, Issue 12, pages 3280–3294, December 2006
How to Cite
Coan, P.M., Conroy, N., Burton, G.J. and Ferguson-Smith, A.C. (2006), Origin and characteristics of glycogen cells in the developing murine placenta. Dev. Dyn., 235: 3280–3294. doi: 10.1002/dvdy.20981
- Issue published online: 10 NOV 2006
- Article first published online: 12 OCT 2006
- Manuscript Accepted: 10 SEP 2006
- Anatomical Society of Great Britain and Ireland
- Isaac Newton Trust, Trinity College, Cambridge
- glycogen cells;
- junctional zone;
- genomic imprinting;
The junctional zone (Jz) of the mouse placenta consists of two main trophoblast populations, spongiotrophoblasts and glycogen cells (GCs), but the development and function of both cell types are unknown. We conducted a quantitative analysis of GC size, number, and invasion of cells into the decidua across gestation. Furthermore, we identified markers of GC function to investigate their possible roles in the placenta. While the spongiotrophoblast cell volume doubles, and cell number increases steadily from E12.5 to E16.5, there is a remarkable 80-fold increase in GC numbers. This finding is followed by a notable decrease by E18.5. Surprisingly, the accumulation of GCs in the decidua did not fully account for the decrease in GC number in the Jz, suggesting loss of GCs from the placenta. Glucagons were detected on GCs, suggesting a steady glucose release throughout gestation. Connexin31 staining was shown to be specific for GCs. GC migration and invasion may be facilitated by temporally regulated expression of matrix metalloproteinase 9 and the imprinted gene product, Decorin. Expression of the clearance receptor for type II insulin-like growth factor (IGF-II), IGF2R, in a short developmental window before E16.5 may be associated with regulating the growth effects of IGF-II from glycogen cells and/or labyrinthine trophoblast on the expansion of the Jz. Thus stereology and immunohistochemistry have provided useful insights into Jz development and function of the glycogen cells. Developmental Dynamics 235:3280–3294, 2006. © 2006 Wiley-Liss, Inc.