- 1.
The onset of vitellogenesis in Rhodnius prolixus is marked by a reduction in the height of the follicle cells. This decrease is not observed in follicle cells from allatectomized females. Estimates of the changes in cross-sectional area of the cells suggest that the cells shrink to about 50% of their original volume as the result of JH action.
- 2.
Determination by interference microscopy of the volume of isolated living follicle cells before and after exposure to JH also suggest that the volume is reduced to 50 % of the original volume as a result of JH action. There was no decrease in volume of follicle cells from allatectomized females following exposure to JH.
- 3.
During mid to late vitellogenesis in vivo, an increase in cell volume was measured, an increase that possibly reflects an increase in cellular dry mass.
- 4.
It is concluded that follicle cells normally respond to JH by pumping out fluid, thus reducing their volume, and leading to the development of spaces between the cells.
Note: This work is supported by the National Research Council of Canada
