Progesterone secretion and proliferation in cultured rabbit granulosa cells under conditions of beta-D-xyloside-induced inhibition of proteoglycan synthesis.
Proteoglycans present in follicular fluid are synthesized by granulosa cells under gonadotropin control. An inhibitor of proteoglycan synthesis, p-nitrophenyl-beta-D-xyloside (beta-D-xyloside) was used as a probe to study rabbit granulosa cell steroidogenesis and proliferation under abrogated proteoglycan synthesis. Granulosa cells isolated from rabbit preovulatory follicles were cultured 24 h in Minimum Essential Medium plus 2.5% fetal calf serum in the presence or absence of beta-D-xyloside and were then treated with FSH or dibutyryl cAMP (db-cAMP) alone or in combination with beta-D-xyloside for a further 24 h. The exposure for 48 h of granulosa cells to 1 mM beta-D-xyloside in the absence or presence of FSH inhibited proteoglycan synthesis and increased the amount of glycosaminoglycans (GAG). FSH-stimulated progesterone production was significantly correlated only with proteoglycan synthesis and not with GAG production. The addition of various concentrations of beta-D-xyloside (0.1-4 mM) for 48 h to granulosa cells induced a dose-dependent inhibition of FSH-stimulated progesterone secretion and [3H]thymidine incorporation into DNA. beta-D-Xyloside concentrations lower than 1 mM induced an inhibition of FSH-stimulated progesterone secretion but had no significant effect on FSH-induced proliferation. One millimolar beta-D-xyloside did not modify basal progesterone production, but in the presence of various doses (0.1-2.5 ng/ml) of FSH or hCG (0.1-1 IU/ml) it exerted a significant inhibitory effect on steroid secretion. Fifty percent inhibition was obtained for doses of FSH above 0.5 ng/ml.(ABSTRACT TRUNCATED AT 250 WORDS)
Benhaïm
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A
Laboratoire de Biochimie, ER 90 CNRS-IBBA, CHU Côte de Nacre, Université de Caen, France.
Feral
C
C
Langris
M
M
Bocquet
J
J
Leymarie
P
P
D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002455:Cell Division; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D006027:Glycosides / Q000494:pharmacology*; D006107:Granulosa Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011374:Progesterone / Q000378:metabolism*; D011509:Proteoglycans / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D011817:Rabbits
D006063:Chorionic Gonadotropin; D006027:Glycosides; D011509:Proteoglycans; C010807:xylosides; D011374:Progesterone; D003994:Bucladesine; D005640:Follicle Stimulating Hormone; D004247:DNA; D000242:Cyclic AMP