Ovarian glycosaminoglycans: evidence for a role in regulating the response of the oocyte-cumulus cell complex to FSH.

The effects of sulfated glycosaminoglycans (GAGs) on FSH-stimulated cumulus expansion and hyaluronic acid (HA) synthesis were tested using cumuli oophori isolated from mice. It was found that heparin (Hep), heparin sulfate (HeS) and chondroitin sulfates (CSs) A,B, and C inhibited FSH-stimulated cumulus expansion and HA synthesis. The relative potencies of these GAGs in inhibiting HA synthesis was as follows: Hep greater than HeS congruent to CS-B greater than CS-C greater than CS-A. The GAGs did not block spontaneous oocyte meiotic maturation. It is suggested that the GAGs may function in vivo to block the response of the cumulus cells to FSH indigenous to the Graafian follicle prior to the preovulatory gonadotropin surge.