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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined the effect of direct and indirect Sertoli-germ cell co-culture on androgen binding protein (ABP) and transferrin (TRF) secretion by Sertoli cells (Sc) from 10-, 18-, and 26-day-old rats. Addition of germ cells (Gc), mainly (greater than 80%) pachytene spermatocytes, directly to Sc monolayers enhanced basal and follicle-stimulating hormone (FSH) + testosterone-stimulated ABP and TRF secretion at all three ages. When the Gc were co-cultured indirectly with Sc (separated by a Nucleopore filter), only 50% of the direct stimulatory effect was found at 18- and 26-day-old groups, whereas no difference between direct and indirect co-culture was noted with Sc from 10-day-old rats. With 18- and 26-day-old rat Sc, the Gc effect on ABP and TRF secretion declined after 6 days of Sc culture, reaching the level of Sc-only cultures after 10 days, whereas the direct effect was maintained throughout the entire culture period. With Sc from 10-day-old animals, both direct and indirect effect of Gc decreased after 6 days but the levels of ABP and TRF secretion remained above those of Sc-only cultures. The viability and number of Gc in indirect co-cultures were maintained significantly higher than in Gc-only control cultures. The direct and indirect Gc effect was completely reversed 48 h after the Gc were removed from Sc cultures of 18- and 26-day-old rats, whereas in Sc cultures from 10-day-old rats 40% of the stimulatory effect remained after 48 h of Gc removal. We conclude that Gc can influence Sc secretory activity through both direct contact and some released factor(s). These two pathways may have different relevance at different ages during sexual maturation.
Mol Cell Endocrinol 1989 Jul
PMID:Influence of germ cells on Sertoli cell secretory activity in direct and indirect co-culture with Sertoli cells from rats of different ages. 279 61

The effect of kaurenol (ent-kaur-16-en-15 beta-ol) on steroidogenesis and cyclic AMP production was examined in rat granulosa cells in short-term incubations (6 h). Kaurenol alone significantly augmented the production of progesterone in time- and concentration-dependent manner but attenuated the accumulation of the progesterone metabolite 20 alpha-hydroxypregn-4-en-3-one (20 alpha-OH-P). The steroidogenic effect of kaurenol is due to the acute stimulation of pregnenolone production from endogenous cholesterol and an inhibition in 20 alpha-hydroxysteroid dehydrogenase which catalyzes the metabolism of progesterone to 20 alpha-OH-P. Kaurenol had no appreciable effect on conversion of exogenous pregnenolone to progesterone. Although kaurenol was without effect on basal cyclic AMP generation, it inhibited the actions of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and forskolin on the production of the cyclic nucleotide. Kaurenol also significantly attenuated the LH-, FSH- and forskolin-stimulated progesterone and 20 alpha-OH-P production in a concentration-dependent manner. Because kaurenol induced steroidogenesis without increased cyclic AMP accumulation, it is concluded that its action on basal steroidogenesis is mediated by a mechanism independent of the cyclic nucleotide. Kaurenol may serve as a useful tool for elucidating cyclic AMP-independent action(s) of hormones in intact tissue/cells.
Mol Cell Endocrinol 1988 May
PMID:The effect of kaurenol on steroidogenesis and cyclic adenosine monophosphate production in rat granulosa cells. 284 Mar 12

Interactions between signal transducing systems may be important in the integrated control of cellular processes in basal and hormonally regulated cells. The swine granulosa cell provides a model to study the interactions between the cAMP and calcium-lipid-dependent signaling pathways. To this end, porcine granulosa cells were incubated in monolayer culture for 1-4 days in the presence of FSH (200 ng/ml), forskolin (85 microM), or cholera toxin (3 micrograms/ml) with or without an activator of protein kinase C, the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) (30 ng/ml). TPA had little effect on basal cAMP generation (1-4 days) or on follicle-stimulating hormone (FSH)-stimulated cAMP formation during the first 24 h. Phorbol ester did inhibit cAMP formation on day 2 (by approximately 25%), on day 3 (by approximately 70%) and on day 4 (by greater than 80%). Forskolin-mediated cAMP generation was inhibited (33-56%) on days 1-4, respectively. TPA suppressed dose-dependent FSH (3-300 ng/ml)-stimulated cAMP production on day 2, virtually abolished FSH-provoked cAMP formation on day 4 and inhibited dose-dependent forskolin-stimulated cAMP production on both days. TPA had no effect on the half-maximally effective dose, ED50, of FSH-stimulated cAMP production but did decrease the ED50 of forskolin and the maximal stimulatory effect of FSH and forskolin on days 2 and 4. Similar effects were observed with the synthetic diacylglycerols DOG (1,2-dioctanoylglycerol) and OAG (1-oleoyl-2-acetylglycerol). The TPA effect was limited to the mammalian adenylate cyclase as it had no effect on bacterially derived adenylate cyclase from Bordetella pertussis.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Cell Endocrinol 1988 Oct
PMID:Interactions of protein kinase C with receptor- and non-receptor-mediated cyclic AMP generation in swine granulosa cells. 284 82

Granulosa cells from immature female rats, pretreated with pregnant mare's serum gonadotropin, were cultured with microcarrier beads for 24 h, and superfused with culture medium. Progesterone was transiently released following a 10-min pulse of FSH (100 ng/ml), and there was a self-priming effect of FSH. 10-min pulses of 8-bromo-adenosine 3',5'-cyclic monophosphate (8Br-cAMP) (1 mg/ml) mimicked the effects of follicle-stimulating hormone (FSH). Continuous superfusion with FSH induced biphasic secretion of progesterone, which was composed of a parabolic (the first) and a plateau (the second) phase. By contrast, the pattern of secretion induced by continuous superfusion with 8Br-cAMP was monophasic. FSH-stimulated secretion of progesterone was rapidly inhibited by the addition of 10 microM cycloheximide (CX), but secretion recovered upon removal of this inhibitor. In the second phase, the recovery of secretion was accompanied by an overshoot of the plateau value. The present results suggest that: (1) the generation of the time-related biphasic pattern of secretion cannot be interpreted by cAMP alone; (2) FSH stimulates the secretion of progesterone by a mechanism that involves newly synthesized protein.
Mol Cell Endocrinol 1988 Oct
PMID:Dynamic response to follicle-stimulating hormone of secretion of progesterone by superfused rat ovarian granulosa cells. 284 83

Inhibitory (A1) adenosine receptors that attenuate adenylate cyclase activity are present in cultured Sertoli cells. To investigate the possible effect of activating these receptors on the secretion of inhibin by the Sertoli cell, immature rat Sertoli cells were incubated for 24 h with follicle-stimulating hormone (FSH) in the absence or presence of the non-metabolizable, adenosine agonist phenyl-isopropyl-adenosine (PIA), and the accumulation of alpha-inhibin immunoreactivity was measured in the medium. Although devoid of effects when added alone, PIA inhibited the FSH-dependent secretion of alpha-inhibin in a concentration-dependent manner (ED50 = 1-1.5 nM). PIA treatment of the Sertoli cells also rendered the cells less sensitive to FSH in terms of alpha-inhibin secretion. The concentration-response curve to FSH was shifted to the right when cells were incubated in the presence of 100-1000 nM PIA. In contrast, dibutyryl cAMP stimulation of alpha-inhibin accumulation was unaffected by treatment with PIA, indicating that the site of PIA action is at the level of cAMP synthesis. These data provide experimental evidence of adenosine modulation of inhibin secretion by the Sertoli cell and suggest that adenosine may act as a local modulator within the pituitary-testicular axis.
Mol Cell Endocrinol 1988 Oct
PMID:Adenosine receptor-dependent modulation of inhibin secretion in cultured immature rat Sertoli cells. 284 85

Aromatase is an enzyme complex that is composed of a specific form of cytochrome P-450 and a flavoprotein, NADPH-cytochrome P-450 reductase. Aromatase activity of granulosa cells is increased markedly by follicle-stimulating hormone (FSH) and by analogs of cyclic AMP. It was the objective of the present study to investigate the effects of FSH and dibutyryl cyclic AMP (Bt2cAMP) on the synthesis of NADPH-cytochrome P-450 reductase in rat granulosa cells maintained in vitro. Granulosa cells were obtained from the ovaries of diethylstilbestrol (DES)-treated immature rats and were incubated in the presence of DES (10(-7) M), DES + FSH (250 ng/ml), or DES + Bt2cAMP (1 mM) for up to 72 h. After 72 h of incubation, aromatase activity of cells incubated with DES alone was 5 pmoles estrogen formed 2 h-1 mg-1 protein and was increased greater than 60-fold in cells incubated with FSH or Bt2cAMP. NADPH-cytochrome P-450 reductase was immunoisolated from [35S]methionine-labeled lysates of granulosa cells incubated for 72 h in the absence or presence of stimulatory factors. The rate of synthesis of reductase was found to be increased about 3-fold in cells incubated with DES + FSH or DES + Bt2cAMP as compared to cells incubated with DES alone. By immunoblot analysis we found that the cellular content of reductase was increased about 2-fold by FSH and Bt2cAMP treatment. Reductase specific activity was 10 nmoles min-1 mg-1 protein in membrane fractions of DES-treated cells and was increased 1.6-fold by FSH treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Cell Endocrinol 1985 May
PMID:Regulation of aromatase activity of rat granulosa cells: induction of synthesis of NADPH-cytochrome P-450 reductase by FSH and dibutyryl cyclic AMP. 298 33

Studies on granulosa cell responses in vitro have routinely utilized cell preparations in which intercellular gap-junctions are maintained. The present study was conducted to determine if disruption of these junctions, prior to culture, would affect subsequent follicle-stimulating hormone (FSH)-stimulated luteinizing hormone (LH) receptor induction on these cells. Granulosa cells were expressed from ovaries of diethylstilbestrol (DES)-primed immature rats after a short incubation of the excised ovaries in culture medium alone or medium containing 6.8 mM EGTA. The latter procedure disrupts gap-junctions between granulosa cells thus providing a predominantly mono-dispersed cell suspension. The two cell preparations were cultured, separately, for 72 h in sterile polypropylene tubes in media containing either FSH or FSH plus various steroids (estradiol, testosterone, or 5 alpha-dihydrotestosterone (DHT)). LH receptor content of cells was determined at 72 h of culture. Both the cell yield and the proportion of viable cells obtained were enhanced by the EGTA pretreatment. LH receptors were induced in all FSH-containing cultures of non-dispersed granulosa cells. In the dispersed cell cultures, FSH alone failed to induce LH receptors. The inclusion of either estradiol or testosterone but not DHT with FSH, however, restored LH receptor induction to levels comparable to non-dispersed cultures. LH receptors were not induced in cultures of either cell preparation with steroids alone. Aromatase activity, however, was stimulated in both cell preparations by FSH alone. These results suggest that cell-cell communication may be necessary for LH receptor induction in granulosa cells and that estradiol (or an aromatizable androgen) can promote intercellular interactions if this communication has been disrupted.
Mol Cell Endocrinol 1986 Sep
PMID:Luteinizing hormone receptor induction in dispersed granulosa cells requires estrogen. 301 85

The enzymatic metabolism of estradiol (E2) to the catecholestrogens, 2-hydroxyestradiol (2-OH-E2) and 4-hydroxyestradiol (4-OH-E2) in granulosa cells has been reported. Therefore, we evaluated the effects of these compounds and compared them to those of E2 on porcine granulosa cells cultured in serum-free medium. Cultures of granulosa cells were exposed to various treatments of E2, 2-OH-E2, 4-OH-E2 and(or) follicle-stimulating hormone (FSH) for 4 days and concentrations of progesterone in medium and cell numbers were determined. After 4 days of treatment, 2-OH-E2 and 4-OH-E2 stimulated basal progesterone production by granulosa cells, but 4-OH-E2 was less effective than 2-OH-E2. 2-OH-E2 (1 microgram/ml) stimulated progesterone production by 3.3 +/- 0.6-fold (n = 6 experiments), whereas E2 (1 microgram/ml) stimulated progesterone production 9.9 +/- 1.7-fold (n = 6 experiments). 2-OH-E2 at 4 micrograms/ml further stimulated progesterone production to 10.7 +/- 2.2-fold above controls (n = 9 experiments), whereas 4 micrograms/ml of E2 did not cause further stimulation of progesterone production. Thus, the average potency of 2-OH-E2 was less than E2. Concurrent treatment with 2-OH-E2 (4 micrograms/ml) and saturating concentrations of E2 resulted in further significant increases in progesterone production above the effects of either single treatment both in the absence and presence of FSH (200 ng/ml).(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Cell Endocrinol 1987 Mar
PMID:Catecholestrogens stimulate progestin secretion by cultured porcine granulosa cells. 303 96

Conditioned medium from cultured peritubular cells (PTCM) was capable of increasing the incorporation of amino acids into acid-precipitable material in cultured Sertoli cells, while the incorporation of uridine into acid-precipitable material was unaffected. PTCM did not influence intracellular cAMP accumulation in a manner similar to follicle-stimulating hormone (FSH). PTCM was able to stimulate androgen-binding protein (ABP) secretion by Sertoli cells even in the presence of a maximal dose of FSH. PTCM increased the rate at which peptides are elongated 5-fold over control medium or medium from control fibroblasts. These studies indicate that peritubular cells influence Sertoli cells through different mechanisms than FSH and exert their influence, at least in part, at the level of translation by increasing the rate of peptide elongation.
Mol Cell Endocrinol 1987 Jul
PMID:Peritubular cells influence Sertoli cells at the level of translation. 304 Apr 93

The effect of follicle-stimulating hormone (FSH) on cholesterol biosynthesis was studied using a recently developed serum-free medium for the culture of porcine granulosa cells. Both cell proliferation and progesterone production were shown to be dependent on de novo cholesterol synthesis in studies with an inhibitor of HMG-CoA reductase. Under basal conditions, mevalonate levels appeared to be rate-limiting for steroidogenesis but not for cell growth. FSH treatment increased [1-14C]acetate incorporation into sterols and the intracellular content of free and esterified cholesterol. These effect were not abolished when steroidogenesis was inhibited at the cholesterol side-chain cleavage step. Estradiol also stimulated [1-14C]acetate incorporation into sterols. Quantification of progesterone secretion after blockade of cholesterol synthesis revealed the presence of intracellular pools of precursor sterols which required depletion before progesterone secretion ceased. These pools, which were tentatively ascribed to cholesterol and pregnenolone, were increased in FSH-treated cells. Stimulation of cholesterol biosynthesis may play a fundamental role in FSH action on these cells.
Mol Cell Endocrinol 1986 Mar
PMID:FSH increases the synthesis and stores of cholesterol in porcine granulosa cells. 308 95


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