An autoradiographic study using [3H]glucosamine of gonadotrophin regulation of proteoglycan and glycoprotein synthesis in developing mouse follicles.

Autoradiography of serial sections of ovaries of immature mice was used, after an injection of [3H]glucosamine, to follow the migration of newly synthesized macromolecules into preantral follicles during the period of treatment with PMSG and hCG. [3H]Glucosamine was injected at the same time as the PMSG or 2-h before the time of autopsy. PMSG stimulated a modest uptake of [3H]glucosamine into the zona pellucida of preantral follicles. However, the in-vivo synthesis of labelled macromolecules increased substantially during the period of hCG stimulation, especially in those mice in which the label was injected at the same time as the PMSG. After both short and longer term exposure to [3H]glucosamine, the maximum uptake of label in preantral follicles occurred 4-8 h after the injection of hCG, indicating that hCG rather than PMSG probably exerts the greatest control over the uptake and incorporation of [3H]glucosamine into the zona pellucida and oocyte of preantral follicles. It is suggested that [3H]glucosamine is largely incorporated into non-sulphated glycosaminoglycans.