Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Using ABP as an index of Sertoli cell secretory function, several important features of the Sertoli cell have emerged: 1. The stimulation of ABP production by FSH clearly points to the Sertoli cell as a target cell for FSH (3,4,9-16,21,24). 2. The dramatic effects of androgens on ABP production both in immature and mature rats also suggest that the Sertoli cell is a target cell for androgen (3,12,14,16,25). 3. The striking reduction in ABP production in the cryptorchid testis raises the question whether impairment of Sertoli cell function is the primary reason for the loss of germ cells that occurs in this condition (20). 4. Drugs like nitrofurazone or ethionine, or X-irradiation only slightly affect the secretory function of the Sertoli cells (ABP production), indicating that these treatments most probably have direct effects on the germ cells as well. Thus, measurement of ABP production rate is a very important tool in order to evaluate how hormones, drugs and physical injuries might affect the secretory function of the Sertoli cell. This test system might be of great use in order to study the physiology and hormonal regulation of the Sertoli cells. It might also be valuable in pharmacological and toxicological studies.
Curr Top Mol Endocrinol 1975
PMID:Testicular androgen binding protein (ABP) - a parameter of Sertoli cell secretory function. 1 22

The aromatization of testosterone has been studied in Sertoli cell-enriched cultures derived from 19-day-old rats. It was found that, besides dbcAMP and FSH, several neurotransmitters have a stimulatory effect. At a concentration of 10(-5) M, the strongest effects were noted with L-isoproterenol, L-norepinephrine, L-epinephrine and D,L-synephrine. Some stimulation was observed with dopamine, whereas histamine, melatonin and serotonin as well as acetylcholine and pilocarpine were ineffective. Experiments with alpha- and beta-adrenergic antagonists suggest that beta 2- and maybe also alpha-receptors are involved. The same maximal level of stimulation was generally observed for dbcAMP, FSH and isoproterenol. No further increase in activity was obtained with combinations of these compounds. It is concluded that adrenergic agonists may play a role in testicular development and function.
Mol Cell Endocrinol 1979 Mar
PMID:Stimulation effect of neurotransmitters on the aromatization of testosterone by Sertoli cell-enriched cultures. 3 15

Removal of Ca2+ from the incubation medium by addition of 2 mM ethylene glycol bis-(beta-aminoethyl ether)-N, N'tetraacetic acid (EGTA) leads to at least 75% inhibition of the luteinizing hormone-releasing hormone (LH-RH)-induced accululation of adenosine 3'5'-monophoshpate (cyclic AMP) in rat anterior pituitary gland in vitro. This inhibitory effect of EGTA is reversed by the addition of Ca2+. A half-maximal effect of Ca2+ on LH-RH--induced cyclic AMP accumulation is observed at 2-5 X 10-5 M free Ca2+. The LH-RH-induced LH and FSH release is completely dependent upon the presence of Ca2+ in the incubation medium, a half-maximal effect being measured at 1-2 X 10-4 M free Ca2+. The basal release release of LH is increased upon Ca2+ removal.
Mol Cell Endocrinol 1975 Jan
PMID:Calcium requirement for stimulation of cyclic AMP accumulation in anterior pituitary gland by LH-RH. 16 1

LH- and FSH-sensitive adenylate cyclase activity was present in homogenates of whole testis tissue as well as in microdissected seminiferous tubules derived from young rats. In homogenates of seminiferous tubules a single adenylate cyclase appears to interact with both LH and FSH through separate hormone-specific receptors. Disruption of testis tissue by homogenization exposes functional FSH and LH receptors which are inaccessible to the hormones in intact cell preparations. These results indicate that in certain seminiferous tubule cell types only a fraction of the total functional receptors present is accessible to the cell surface for interaction with hormone.
Mol Cell Endocrinol 1976 Feb
PMID:LH- and FSH-stimulating of adenylate cyclase in seminiferous tubules from young rats: functional FSH and LH receptors unmasked by homogenization. 17 66

When various doses of testosterone propionate (10 to 10,000 mug/day) were given to 21-day-old rats for 10 days a biphasic effect was seen both on testis weight and production of androgen-binding protein (ABP). At low doses (10 to 100 mug testosterone propionate/day) there was a reduction in testis weight as well as ABP content in the epididymis. At higher doses of testosterone propionate, there was a stimulation of both testicular weight and ABP production in spite of suppressed serum FSH and LH levels. These effects of testosterone propionate on Sertoli cell secretory function strongly suggest that the Sertoli cell is a target cell for androgen.
Mol Cell Endocrinol
PMID:Biphasic effect of testosterone propionate on Sertoli cell secretory function. 18 71

Granulosa cells from preovulatory follicles (PO) or from the enlarged preantral follicles of hypophysectomized immature diethylstilbestrol-treated (Hx-DES) rats were cultured with various combinations of FSH, androst-4-ene-3,17-dione (Ad), estradiol-17beta and dibutyryl cyclic AMP (dbcAMP). Progestin levels (progesterone and 20alpha-dihydroprogesterone) in the medium after 2 days of culture were assayed by radioimmunoassay. The control levels of the two progestins were lower for Hx-DES than for PO cells. Rat FSH (NIAMD-1-3;0.1 mug/ml) caused a 2-fold rise in progestin accumulation in both PO and Hx-DES cultures, dbcAMP (1 mM) increased progestin accumulation in PO cultures 4-5-fold, and to an even greater extent (10-20 fold) in Hx-DES cultures. Androstenedione (1.0 mug/ml) augmented progestin accumulation (1.5-3-fold), and synergized the steroidogenic action of FSH: in cells from Hx-DES rats, combined treatment with FSH and Ad caused a 5-10-fold increase over the values obtained with FSH alone. Testosterone and 5alpha-dihydrotestosterone, but not estradiol-17beta or estrone, mimicked these effects of Ad, Ad did not synergize the action of dbcAMP on progestin levels in Hx-DES cultures. It is proposed that androgen may play a role in the development of the FSH-responsive mechanism in preantral granulosa cells.
Mol Cell Endocrinol
PMID:A synergistic effect of androgen on the stimulation of progesterone secretion by FSH in cultured rat granulosa cells. 18 82

Specific receptors for iodine-labelled human prolactin ([125I]hPrl) are present in membrane preparations of the rat ventral prostate. The binding is saturable with an apparent association constant (Ka) of 2.2 X 10(9) M-1 and a binding capacity of about 1 pmol/100mg prostatic tissue. The binding of [125I]hPrl is inhibited by hPrl, ovine Prl (otprl) and human growth hormone, but not by ovine FSH or LH. Serum from rats having Prl-producing pituitary tumors caused a displacement of the [125I]hPrl from the receptors, and the displacement curve was parallel with that of the hPrl standard. Treatment of immature rats with varying doses of dihydrotestosterone propionate (10-5000 microng) causes a dose-dependent stimulation of Prl receptors calculated both as binding sites per mg of membrane protein and as binding sites per prostate. Androgen stimulation of prostatic Prl receptors increases the tissue sensitivity for circulating Prl and may be one reason for the known increases in endogenous cAMP levels in prostatic tissue after androgen treatment in vivo.
Mol Cell Endocrinol 1977 Mar
PMID:Androgen stimulation of prolactin receptors in rat prostate. 19 11

Cultures of granulosa cells from immature hypophysectomized DES-treated rats were unable to maintain progestin production of more than 48 h in medium without hormone supplementation or in the presence of FSH only. Production of progestin (20alpha-dihydroprogesterone, as measured by radioimmunoassay) remained unimpaired in the presence of androstenedione (Ad) and was markedly increased in the presence of both Ad and FSH. The combined treatment with FSH and Ad during the first 48 h of culture brought about persistent changes in the cultured cells, since progestin accumulation did not decline upon subsequent removal of these hormones during days 3 and 4 of culture. Dibutyryl cyclic AMP (DBC) was able to mimic the changes in steroidogenic capability induced by the combined action of FSH and Ad. The extent of [125I]-FSH binding, FSH-stimulable cAMP accumulation and cyclic 3',5'-nucleotide phosphodiesterase activity were not affected by addition of Ad to the culture medium. Ad synergized with DBC in the stimulation of progestin accumulation in granulosa cell cultures. It is suggested that androgen acts at a step in the regulation of progestin biosynthesis distal to cAMP production.
Mol Cell Endocrinol 1977 Sep
PMID:Studies on the synergistic effect of androgen on the stimulation of progestin secretion by FSH in cultured rat granulosa cells: a search for the mechanism of action. 20 May 8

This study examines the effect of FSH, testosterone and estradiol on testicular LH receptors and in vitro testicular responsiveness to LH in immature rats under various conditions. FSH treatment of 15-day-old immature rats significantly increased the number of LH receptors but did not alter testicular responsiveness. FSH treatment of hypophysectomized immature rats increased the number of LH receptors and markedly increased testicular responsiveness. Treatment of hypophysectomized rats with testosterone proprionate for 4 days, followed by a 5-day treatment with FSH, enhanced the effect of FSH on the number of LH receptors but did not increase the effect of FSH on testicular responsiveness. In contrast, treatment with estradiol for 4 days before FSH treatment had no effect on the FSH-induced increase in LH receptors but completely inhibited the FSH-induced increase in testicular responsiveness. These observations suggest that during male sexual maturation (1) regulation of LH receptors is distinct from regulation of testicular responsiveness to LH, (2) estradiol may be a factor in the regulation of testicular responsiveness to LH, and (3) testosterone may enhance the FSH-induced increase of LH receptors.
Mol Cell Endocrinol 1977 Oct
PMID:Steroid and FSH action on LH receptors and LH-sensitive testicular responsiveness during sexual maturation of the rat. 20 May 10

Intratesticular injection of 25 microgram rat FSH into rats under continuous urethane anaesthesia resulted 24 h later in a 50% reduction in binding sites for FSH in testicular homogenates. By 48 h after injection, receptor number usually returned to control values. Intratesticular injection of 125I-labelled rat RSH showed less than 1% remaining in the testis 24 h later, suggesting that the reduction in receptor numbers at 24 h is not due to occupancy by the FSH. Experiments did not suggest that the injection of FSH induced FSH-degrading enzymes or inhibitors of binding.
Mol Cell Endocrinol 1978 Oct
PMID:Reduction in FSH receptors in the rat testis by injection of homologous hormone. 21 62


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