Matches in SemOpenAlex for { <https://semopenalex.org/work/W2000773736> ?p ?o ?g. }
Showing items 1 to 91 of
91
with 100 items per page.
- W2000773736 abstract "The major source of ovarian androgen is the theca cells. Androgens are produced by the conversion of progestins by the 17 alpha-hydroxylase/C17,20 lyase enzymatic system (lyase). The 3 beta-hydroxysteroid dehydrogenase and aromatase enzymes in the theca cells are modulated by gonadotropins as well as by steroids produced locally. Therefore, the combined effects of hCG plus progesterone, estradiol, or dihydrotestosterone (DHT) on microsomal lyase activity in theca cells from large and medium-sized follicles were determined. Theca cells (3 x 10(6) cells/6 ml/well) were cultured in Medium 199 (M199) containing only insulin (10 micrograms/ml) and transferrin (5 micrograms/ml). At 24 h, theca cells were treated with M199, hCG (15 ng/ml), progesterone, estradiol, or DHT (100 ng/ml) or a combination of hCG + one of the three steroids. Media were removed at various times of culture (27-72 h) and levels of androgen determined by RIA. Microsomes were incubated with 1 microCi [3H]progesterone +0.5 mM NADPH and radioactive conversion products were measured after purification by thin layer chromatography. Administration of progesterone, estradiol, or DHT alone had little effect on lyase activity in theca cells from medium-sized follicles whereas the addition of hCG alone significantly increased lyase activity in these cells. However, concomitant addition of any steroid with hCG inhibited the increase in lyase activity after the addition of hCG alone. Theca cells from large porcine follicles had a higher basal level of lyase activity compared to theca cells from the smaller follicles. Lyase activity in theca cells from large follicles was enhanced by progesterone; estradiol was inhibitory. DHT initially stimulated lyase activity in theca cells from large follicles, but was inhibitory later in culture. In contrast to its marked effect on theca cells from medium follicles, hCG had only a small effect on lyase activity in theca cells from large follicles. Thus, thecal lyase activity increased as the follicle matured, providing more androgen substrate for the production of estrogen. Lyase activity in theca cells of medium follicles appears to be regulated predominantly by gonadotropin from the pituitary while intraovarian regulation of lyase activity by steroids may be more important in larger follicles." @default.
- W2000773736 created "2016-06-24" @default.
- W2000773736 creator A5009328081 @default.
- W2000773736 creator A5079197469 @default.
- W2000773736 date "1989-08-01" @default.
- W2000773736 modified "2023-09-25" @default.
- W2000773736 title "Modulation of 17α-hydroxylase/C17,20-lyase activity in porcine theca cells" @default.
- W2000773736 cites W1504821571 @default.
- W2000773736 cites W1587832347 @default.
- W2000773736 cites W1964143393 @default.
- W2000773736 cites W1964769283 @default.
- W2000773736 cites W1968656312 @default.
- W2000773736 cites W1985074947 @default.
- W2000773736 cites W1993035190 @default.
- W2000773736 cites W1996271021 @default.
- W2000773736 cites W2000341652 @default.
- W2000773736 cites W2022599111 @default.
- W2000773736 cites W2039231599 @default.
- W2000773736 cites W2043940037 @default.
- W2000773736 cites W2044027914 @default.
- W2000773736 cites W2054554622 @default.
- W2000773736 cites W2059859570 @default.
- W2000773736 cites W2073999862 @default.
- W2000773736 cites W2075968891 @default.
- W2000773736 cites W2083957753 @default.
- W2000773736 cites W2114060838 @default.
- W2000773736 cites W2114907849 @default.
- W2000773736 cites W2135470634 @default.
- W2000773736 cites W2146666423 @default.
- W2000773736 cites W4293247451 @default.
- W2000773736 doi "https://doi.org/10.1016/0022-4731(89)90303-8" @default.
- W2000773736 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/2788776" @default.
- W2000773736 hasPublicationYear "1989" @default.
- W2000773736 type Work @default.
- W2000773736 sameAs 2000773736 @default.
- W2000773736 citedByCount "5" @default.
- W2000773736 crossrefType "journal-article" @default.
- W2000773736 hasAuthorship W2000773736A5009328081 @default.
- W2000773736 hasAuthorship W2000773736A5079197469 @default.
- W2000773736 hasConcept C121608353 @default.
- W2000773736 hasConcept C126322002 @default.
- W2000773736 hasConcept C134018914 @default.
- W2000773736 hasConcept C175805485 @default.
- W2000773736 hasConcept C181199279 @default.
- W2000773736 hasConcept C185592680 @default.
- W2000773736 hasConcept C2776166826 @default.
- W2000773736 hasConcept C2776986892 @default.
- W2000773736 hasConcept C2777269803 @default.
- W2000773736 hasConcept C2777911890 @default.
- W2000773736 hasConcept C2778324911 @default.
- W2000773736 hasConcept C2779881493 @default.
- W2000773736 hasConcept C530470458 @default.
- W2000773736 hasConcept C55493867 @default.
- W2000773736 hasConcept C71315377 @default.
- W2000773736 hasConcept C71924100 @default.
- W2000773736 hasConcept C86803240 @default.
- W2000773736 hasConceptScore W2000773736C121608353 @default.
- W2000773736 hasConceptScore W2000773736C126322002 @default.
- W2000773736 hasConceptScore W2000773736C134018914 @default.
- W2000773736 hasConceptScore W2000773736C175805485 @default.
- W2000773736 hasConceptScore W2000773736C181199279 @default.
- W2000773736 hasConceptScore W2000773736C185592680 @default.
- W2000773736 hasConceptScore W2000773736C2776166826 @default.
- W2000773736 hasConceptScore W2000773736C2776986892 @default.
- W2000773736 hasConceptScore W2000773736C2777269803 @default.
- W2000773736 hasConceptScore W2000773736C2777911890 @default.
- W2000773736 hasConceptScore W2000773736C2778324911 @default.
- W2000773736 hasConceptScore W2000773736C2779881493 @default.
- W2000773736 hasConceptScore W2000773736C530470458 @default.
- W2000773736 hasConceptScore W2000773736C55493867 @default.
- W2000773736 hasConceptScore W2000773736C71315377 @default.
- W2000773736 hasConceptScore W2000773736C71924100 @default.
- W2000773736 hasConceptScore W2000773736C86803240 @default.
- W2000773736 hasLocation W20007737361 @default.
- W2000773736 hasLocation W20007737362 @default.
- W2000773736 hasOpenAccess W2000773736 @default.
- W2000773736 hasPrimaryLocation W20007737361 @default.
- W2000773736 hasRelatedWork W187037284 @default.
- W2000773736 hasRelatedWork W1984439683 @default.
- W2000773736 hasRelatedWork W2011193016 @default.
- W2000773736 hasRelatedWork W2070975009 @default.
- W2000773736 hasRelatedWork W2075052643 @default.
- W2000773736 hasRelatedWork W2075574887 @default.
- W2000773736 hasRelatedWork W2088005812 @default.
- W2000773736 hasRelatedWork W2099035232 @default.
- W2000773736 hasRelatedWork W2110010322 @default.
- W2000773736 hasRelatedWork W2172208311 @default.
- W2000773736 isParatext "false" @default.
- W2000773736 isRetracted "false" @default.
- W2000773736 magId "2000773736" @default.
- W2000773736 workType "article" @default.