Follicle-Stimulating Hormone Stimulates Ovarian Synthesis of Proteoglycans in the Estrogen-Stimulated Hypophysectomized Immature Female Rat*

FSH stimulates antrum formation, but the mechanisms involved have remained obscure. Because antral fluid contains proteoglycans, we have studied the incorporation of 35SC4 into ovarian proteoglycans in estrogen-primed hypophysectomized immature female rats in which antrum formation was stimulated by administration of ovine FSH, highly purified human FSH, and/or hCG. Two days after hypophysectomy and insertion of a silastic capsule containing diethylstilbestrol, graded doses of ovine FSH (NIH S-ll) were injected sc twice daily for 4 days. On day 4, 35SC4 (200–300 /μCi) was given ip and the animals were sacrificed 24 h later. The ovaries were homogenized, the 100,000 × g supernatants filtered through 0.025 μn Millipore filters, and the non-filterable radioactivity determined. The non-filterable radioactivity was macromolecular proteoglycans, because incubation with chondroitinases AC or ABC (with or without papain pretreatment) resulted in a 75% decrease in non-filterable radioactivity, and the degradation ...