Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
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An androgen binding protein (ABP) with an electrophoretic mobility (Rf) of 0.56 is present in the rete testis fluid of adult rams. Its steroid specificity was found to be in the following order: 5alpha-DHT, testosterone, oestradiol-17 beta, dehydroepiandrosterone 5beta-DHT, androstenedione, cyproterone, cyproterone acetate, cortisol and progesterone. The characteristics of the ABP are similar to those found for the ABP of the testis and the epididymis of the rat and the rabbit. The concentration of ABP, determined by the dextran-coated charcoal method and sometimes confirmed by the steady-state polyacrylamide gel electrophoresis method, was significantly higher in the breeding season than in the non-breeding season (4.40 +/- 0.98 X 10(-9) M vs. 2.60 +/- 0.62 X 10(-9) M; P less than 0.037). The affinity constant of the ABP was independent of the season (2.45 +/- 0.21 X 10(9) M-1 vs. 2.66 +/- 0.1 X 10(9) M-1; NS). In addition, ABP was positively correlated with 5alpha-DHT (r = 0.506; P less than 0.0009), testosterone (r = 0.445; P less than 0.0003), total protein (r = 0.329; P less than 0.02) and spermatozoa (r = 0.406; P less than 0.006) in the RTF and with blood plasma testosterone (r = 0.584; P less than 0.0001). Furthermore, testosterone and 5alpha-DHT in RTF were positively correlated (r = 0.582; P less than 0.0001). These androgens were also correlated with plasma testosterone (r = 0.262, P less than 0.052 for testosterone in RTF; r = 0.341, P less than 0.018 for 5 alpha-DHT). Total proteins and spermatozoa were found to be positively correlated in the RTF (r = 0.789; P less than 0.0001).
Mol Cell Endocrinol 1978 Jan
PMID:Studies of the androgen binding protein in the rete testis fluid of the ram and its relation to sexual season. 2 74

Two distinct steroid-binding proteins are present in rabbit plasma. One of the proteins (TeBG) binds [3-H]5 alpha-dihydrotestosterone (5 alpha DHT) and [3-H]testosterone. The affinity of this binding protein for 5 alpha DHT was 3-4 times greater than for testosterone. Binding of [3-H]5 alphaDHT could be inhibited by unlabeled 5 alpha DHT, testosterone, 5 alpha-androstan-3 alpha,17 beta-diol (3 alpha-diol), and 17 alpha-methyl- B-testosterone (skf) 7690). The relative affinity of the competitors was: 5 alpha DHT greater than 3 alpha-diol greater than testosterone greater than SKF 7690. The antiandrogens, cyproterone (1,2 alpha-methylene-6-chloro-pregn-4,6-diene-17 alpla-ol-3,20 dione), cyproterone-17-acetate, and 6 alpha-bromo-17 beta-hydroxy-17 alpha-methyl-4-oxa-5 alpha-androstan-3-ine (BOMT) were ineffective in competing for [3-H5d alpha DHT binding sites, as were 4-androstene-3, 17-dione, 17 beta-estradiol (E2), progesterone, and cortisol. The formation of the [3-H]5 alpha DHT-TeBG complex was extremely rapid; the binding reaction was essentially completed in 15 s. The complex dissociated rapidly in the presence of charcoal. The dissociation rate constant (Kdiss) was 0.157 min- minus 1 and the dissociation half-time t-1/2) was 4.5 min. In the presence of charcoal and unlabeled 5 alpha DHT the Kdiss was 0.268 min- minus 1 and the t=1/2 was 2.6 min. The sedimentation coefficient of TeBG was congruent to 4.6 S and its molecular weight, estimated by gel filtration on a calibrated Sephadex G-200 column, was congruent to 75,000. The concentration of TeBG in male rabbit plasma decreased with sexual maturation and was approximately three times higher in adult females than in adult males. The other protein (CBG) bound both [3-H]cortisol and [3-H]progesterone. Binding of these compounds could be inhibited by unlabeled cortisol and progesterone, but not by unlabeled 5 alpha DHT, testosterone, or E2. CBG had a sedimentation of congruent to 3.9 S and an apparent molecular weight of congruent to 105,000. TeBG could be separated from CBG by a 60% ammonium sulfate precipitation and by gel filtration chromatography. Both proteins are thermolabile; TeBG is inactivated at temperatures above 30 degrees C and CBG is inactivated at temperatures above 50 degrees C.
Mol Cell Endocrinol 1975 May
PMID:Steroid-binding proteins in rabbit plasma: Separation of testosterone-binding globulin (TeBG) from corticosteroid-binding globulin (CBG), preliminary characterization of TeBG, and changes in TeBG concentration during sexual maturation. 4 21

Protein macromolecules specifically binding [3H]5alpha-dihydrotestosterone ([3H]DHT) have been identified in cytosol and in nuclei prepared from human benign hypertrophic prostate. These macromolecules have similar properties to receptor proteins from other androgen-dependent tissues, as regards sedimentation coefficients on sucrose gradients and steroid specificity. Cytosol preparations from androgen-dependent tissues were able to transfer [3H]DHT in a recoverable protein-bound form to nuclei of other androgen-dependent tissues but not to nuclei of androgen-independent tissues. No transfer of radioactive steroid from cytosol of these latter tissues to any nuclei could be achieved. Labelled cytosol preparations from androgen-dependent tissues could stimulate the RNA polymerase activity of nuclei from androgen-dependent tissues but not that of nuclei from androgen-independent tissues. Cytosol preparations from these latter tissues could not affect RNA polymerase activity. Under suitable ionic conditions, human cytosol preparations containing DHT could stimulate both alpha-amanitin-sensitive and -insensitive RNA polymerase activities of human prostatic nuclei. However, rat ventral prostatic DHT-cytosol protein complexes were equally as efficient in performing this function, suggesting the possible involvement of specific DHT-receptor complexes in this process. It is therfore suggested that receptor molecules from androgen-dependent tissues may not be species specific but may share properties which would facilitate research into the understanding and aetiology of pathological conditions.
Mol Cell Endocrinol 1975 Aug
PMID:Similarities between 5alpha-dihydrotestosterone-receptor complexes from human and rat prostatic tissue: effects on RNA polymerase activity. 17 Jan 52

An androgen receptor has been characterized in the cytosol fraction of testes from hypophysectomized adult rams after in vitro labelling with [3H]testosterone. It can be distinguished from the testicular androgen-binding protein (ABP) and from the plasma 5 alpha-dihydrotestosterone-binding protein by electrophoresis on 3.25% acrylamide gels (Rx = 0.5) and on agar gels (anodic migration). It sediments in the 4S region in sucrose gradient containing 0.4 M KCl. Its complex with testosterone dissociates very slowly (t 1/2 = 29 h at 0 degrees C), and is destroyed by heating at 50 degrees C for 30 min and by pronase. Its relative affinities for steroids are 5 alpha-DHT greater than T greater than 5 alpha-androstanediols greater than cyproterone acetate greater than estradiol greater than progesterone. The number of binding sites is limited (about 20 fmoles/mg protein) and the apparent equilibrium dissociation constant (KD) is 5 x 10(-9) M.
Mol Cell Endocrinol 1979 Nov
PMID:Characterization of a cytoplasmic androgen receptor in the ram testis. 51 Jul 71

After i.m. injection of [3H]butyrobetaine into intact and castrated rats, the specific activity of plasma carnitine remained nearly constant over 24--96 h and epididymal uptake of carnitine was constant per unit time up to 72 h. The uptake ratio of intact to castrated rats was high at 48, 72 and 96 h after injection. Administration of estradiol valerate over 20 days reduced carnitine uptake in epididymis. This reduction was dose-dependent when estrogen was administered i.m. at 0.33--10 microgram/day levels. A maximum reduction of 90% was obtained with the 10 microgram dose. A dose increase from 33 to 100 microgram/day caused no further reduction. Norspiroxenone (2--10 mg/day) and SK 7670 (1.5 and 7.5 mg/day) were less effective than estradiol valerate (10 microgram/day) in suppressing carnitine uptake in epididymis. Epididymal carnitine uptake in estradiol valerate treated rats (33 microgram/day for 20 days) increased in a time- and dose-dependent manner under testosterone propionate treatment (50, 250, 1250 microgram/day). Carnitine uptake increased to 80% of the nonsuppressed levels when testosterone propionate was adminsitered over a 6-day period at 1250 microgram/day. Dihydrotestosterone increased epididymal carnitine uptake to the same extent as testosterone propionate. delta4-androstene-3,17-dione and 5alpha-androstane-3alpha,17beta-diol (50 microgram/day) were less effective, stimulating uptake to only 15% and 40% respectively of the testosterone propionate (250 microgram/day) stimulated levels. Changes in epididymal carnitine uptake evoked by various experimental procedures were closely paralleled by weight changes in the ventral prostate. This response resemblance indicates a similarity between the androgen sensitivity of the prostate gland and that of the carnitine uptake system in epididymis. The dose-dependent effect of estrogen on the accumulation of epididymal carnitine, together with the marked responses induced in this system by manipulation of its androgen status, support a possible use for the system as an assay for androgen or antiandrogen potency in vivo.
Mol Cell Endocrinol
PMID:Accumulation of carnitine in rat epididymis after injection of [3H]butyrobetaine in vivo: quantitative aspects, and the effects of androgens and antiandrogens. 68 Mar 41

Cytosol prepared from epididymides of sexually immature (21-23-day-old) rats contains a macromolecular binding component for estradiol-17 beta. This binding moiety sediments as an 8-S species on 5-20% sucrose gradients containing 0.01 M KCl. Under conditions of high ionic strength (0.4 M KCl) the 8-S peak of estradiol binding is shifted to the 4-S region, suggesting dissociation of receptor aggregates. Time-course studies indicated that binding equilibrium was essentially achieved after 2 hours incubation at 0 degrees C. Although unlabeled estrone and estriol are capable of inhibiting [3H]estradiol binding to epididymal cytosol, they are less effective than unlabeled estradiol. Unlabeled 5 alpha-dihydrotestosterone (5 alpha-DHT) at a 100-fold molar excess did not cause a statistically significant inhibition of [3H]estradiol binding. Unlabeled estrogens, but not unlabeled 5 alpha-DHT or cortisol (at the concentrations used), were capable of displacint [3H]estradiol from its binding sites. The dissociation of [3H]estradiol from the binding component is very slow, with half-time of dissociation being greater than 16 hours. The epididymal estrogen binder is saturable at low concentrations of ligand. The dissociation constant was of the order of 10(-11)M and the concentration of binding sites was approximately 10(-14) mol/mg protein. This estrogen binder has the characteristics which are usually attributed to steroid receptors and is clearly different from the testicular androgen-binding protein and the epididymal androgen receptor.
Mol Cell Endocrinol 1977 Feb
PMID:The presence of an estradiol binding component in cytosol from immature rat epididymides. 83 16

The effect of different steroids on the growth of a human cell line, was examined in NHIK 3025 cells, derived from a carcinoma of the uterine cervix. When this cell line was grown in Eagle's minimal essential medium (MEM) for 4 days, addition to the medium of estradiol-17 beta in concentrations ranging from 10(-9) to 10(-7) M did not promote significant cell growth. Stimulated growth was observed with testosterone in these concentrations, with maximal effect (29% above control) at 10(-7) M. 5alpha-Dihydrotestosterone over the range 10(-9)--10(-6) M gave no such effect. 4-Androstene-3,17-dione, 5alpha-androstan-3alpha,17beta-diol and 5alpha-androstan-3beta,17beta-diol had no significant effect on cell proliferation at a concentration of 10(-7) M, while 4-androstene-3beta,17beta-diol augmented cell number to values 50-60% higher than those of control cultures. The observed increase in cell number was due to a shortening of the cell cycle and to a higher plating efficiency. Thus, cell line NHIK 3025 has not the responsiveness to estradiol-17beta of normal uterine cells. The data suggest that testosterone and/or 4-androstene-3beta,17beta-diol may be growth factors for this cell line.
Mol Cell Endocrinol 1976 Oct
PMID:Steroids and growth of a human cell line stemming from a carcinoma of the uterine cervix. 97 91

1. Rabbits received intracisternal injections of 5,6-dihydroxytryptamine (5,6-DHT) in order to ablate central serotonergic nerves and deplete central serotonin stores. Depletion was most marked in the spinal cord where serotonin concentration was reduced to less than 50% of that in rabbits given control injections. 2. In normal rabbits, intracisternal 5,6-DHT caused a transient reduction in arterial pressure, which was maximal 1 week after injection. 3. Intracisternal 5,6-DHT completely prevented the neurogenic hypertension produced by sinoaortic denervation in control animals and reversed it when given after sustained neurogenic hypertension had developed in denervated animals. These studies suggest that central serotonergic neurons participate in the baroreceptor reflex arc. 4. Intracisternal 5,6-DHT did not modify the renal hypertension that follows bilateral renal wrapping.
Clin Sci Mol Med Suppl 1975 Jun
PMID:Central serotonergic neurons and experimental neurogenic and renal hypertension in the rabbit. 107 78

Testicular androgen binding protein (ABP) was purified from the epididymis of 1500 adult rabbits by the sequential use of ammonium sulphate precipitation, ion exchange chromatography on DEAE cellulose, gel filtration on Sephadex G-200, hydroxyl-apatite chromatography and preparative polyacrylamide gel electrophoresis. This procedure yielded a 1000-fold increase in specific activity compared to that of the 1500,000 x g supernatant, and the recovery of active ABP was about 3-5%. ABP is acid glycoprotein with a molecular weight of 65-68,000 daltons. Antisera to rabbit ABP raised in quinea pigs inhibit 3H-DHT binding to ABP as measured by SS-PAGE. When diluted rabbit serum containing TeBG is treated with the same dilutions of these antisera, identical binding inhibition curves are found. Thus, ABP and TeBG in rabbits appear to possess identical immunological determinants.
Curr Top Mol Endocrinol 1975
PMID:Purification and characterization of rabbit testicular androgen binding protein (ABP). 124 82

We have investigated the ability of dehydroepiandrosterone (DHEA) to alter the production of interleukin-2 (IL-2) and to bind to a specific binding complex in antiCD3 epsilon activated T cells. Binding activity correlated with the presence of a specific DHEA binding complex in the cytosol and nuclei of DHEA-responsive T-cell hybridomas, as well as in CD4+ and CD8+ cells isolated from peripheral lymph nodes of normal mice. Scatchard analysis determined that intact lymphocytes and cytosolic fractions contained high affinity binding for [3H]DHEA (approx. 2.6 nM) with 1000-7000 binding sites existing per cell. Five of the T-cell hybridomas tested both responded to DHEA treatment with increased production of IL-2 and also contained specific high affinity [3H]DHEA binding. Four additional T-cell hybridomas were found to contain no specific [3H]DHEA binding and were also unresponsive to DHEA influences on IL-2 production. Sucrose density gradients demonstrated a 3-4s [3H]DHEA binding complex in high salt and a 7-8s binding complex in low salt. Specific binding was inhibited by preincubation of the cytosol fractions with either trypsin or chymotrypsin, or by heating to 60 degrees C for 1 h (less than 15% of control). [3H]DHEA binding was unaffected by preincubation of the cytosol fractions with ribonuclease, deoxyribonuclease, or phospholipase A. The DHEA-protein complexes bound to DNA-cellulose with the amount of binding being slightly increased by preincubation at 25 degrees C as compared to 4 degrees C. As expected, [3H]DHEA binding was inhibited by the addition of unlabeled DHEA, but was also modestly inhibited by dihydrotestosterone and cortisol. Binding of DHEA was unaffected by progesterone, dexamethasone, estradiol, androsterone, DHEAS, and beta-etiocholanolone at all concentrations tested. DHEA was incapable of inhibiting the binding of [3H]DHT to the androgen receptor or [3H]dexamethasone to the glucocorticoid receptor. Collectively, these findings suggest that murine T cells contain a specific DHEA receptor. We believe that DHEA is a steroid hormone that is directly involved in the regulation of IL-2 production by both normal and some T-cell hybridomas.
J Steroid Biochem Mol Biol 1992 May
PMID:The presence of a dehydroepiandrosterone-specific receptor binding complex in murine T cells. 135 1


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