LOCALIZATION OF AN ANDROGEN BINDING SUBSTANCE FROM THE RAT VENTRAL PROSTATE

1969 ◽  
Vol 60 (4) ◽  
pp. 571-578 ◽  
Author(s):  
Olav Unhjem ◽  
Kjell J. Tveter
Keyword(s):  
Gel Filtration ◽  
The Other ◽  
Male Rats ◽  
Ventral Prostate ◽  
Rat Ventral Prostate ◽  
Binding Substance ◽  
Liver And Kidney ◽  
Androgen Binding ◽  
Filtration Technique

ABSTRACT A gel filtration technique has been used for analysing the interaction of testosterone and/or its metabolites with macromolecules in the ventral prostate, rectus abdomonis muscle, liver and kidney from castrated adult male rats. Following administration of (1,2-3H)-testosterone, association of radioactivity with soluble macromolecules was demonstrated in the ventral prostate but not in the other organs analysed. A similar binding was observed when slices of ventral prostate were incubated in vitro with testosterone. When 105 000 × g supernatants from the ventral prostate were incubated with (1,2-3H)-testosterone at 37° C, radioactivity was also recovered associated with macromolecules. No association could be detected when the incubation was performed at 0° C.

POSSIBLE INTERACTION OF LUTEINIZING HORMONE-RELEASING FACTOR WITH OTHER HYPOTHALAMIC RELEASING FACTORS AT THE LEVEL OF THE ADENOHYPOPHYSIS

1969 ◽  
Vol 44 (3) ◽  
pp. 405-410 ◽  
Author(s):  
D. B. CRIGHTON ◽  
H. P. G. SCHNEIDER ◽  
S. M. McCANN
Keyword(s):  
Growth Hormone ◽  
Luteinizing Hormone ◽  
Gel Filtration ◽  
The Other ◽  
Male Rats ◽  
Corticotrophin Releasing Factor ◽  
Lh Release ◽  
Releasing Factors ◽  
Factor C

SUMMARY Anterior pituitary halves from adult male rats were incubated in vitro for 6 hr. in tissue culture Medium 199. Luteinizing hormone (LH) released from these glands under the influence of purified preparations of growth hormone-releasing factor (GH-RF), growth hormone-inhibiting factor (GH-IF), corticotrophin-releasing factor (C-RF) and follicle-stimulating hormone-releasing factor (FSH-RF) was determined by the ovarian ascorbic acid depletion (OAAD) assay. The effects of these factors, both alone and together with purified luteinizing hormone-releasing factor (LH-RF), were examined and compared with the response to purified LH-RF alone. While LH-RF consistently produced significant increases in LH release, none of the other factors did so, although FSH-RF showed some indication of LH-releasing activity, probably due to incomplete separation from LH-RF on the Sephadex gel filtration column used for purification. The LH released in response to LH-RF was not affected by the presence of any of the other factors. An apparent slight augmenting effect of FSH-RF could be accounted for by its contamination with LH-RF. The results are discussed in relation to the physiological mechanisms concerned in modifying LH release from the adenohypophysis.

PARTIAL SEPARATION OF A 3α-KETOSTEROID OXIDOREDUCTASE AND AN ANDROGEN BINDING SUBSTANCE PRESENT IN RAT VENTRAL PROSTATE CYTOPLASM

1970 ◽  
Vol 65 (3) ◽  
pp. 525-532 ◽  
Author(s):  
Olav Unhjem
Keyword(s):  
Enzymatic Activity ◽  
Reduced Glutathione ◽  
Enzymatic Reaction ◽  
Gel Filtration ◽  
Ventral Prostate ◽  
Supernatant Fraction ◽  
Rat Ventral Prostate ◽  
Molecular Sizes ◽  
Androgen Binding ◽  
Fraction Addition

ABSTRACT The presence of a 3α-ketosteroid oxidoreductase in the rat ventral prostate cytoplasm has been demonstrated. The enzyme was confined to the 105 000 × g supernatant fraction with very little activity in the mitochondrial-microsomal fraction. Addition of NADPH2 was necessary for the enzymatic reaction to proceed. The enzymatic activity was lost when supernatant fractions were dialysed against 0.1 m Tris-HCl buffer, pH 7.4 or when chromatographed by gel filtration using the same buffer. When either L-cysteine, reduced glutathione, 2-mercaptoethanol or EDTA was added to the buffer, the enzymatic activity was preserved. The molecular weight of the enzyme was calculated to be 40 000–50 000. 3H-5α-dihydrotestosterone associates with macromolecules in the 105 000 × g supernatant fraction which are of two molecular sizes (60 000–70 000 and ∼ 200 000). These complexes could not be demonstrated by gel filtration using buffers containing either reduced glutathione, 2-mercaptoethanol or EDTA. By using L-cysteine, the small molecular complex was preserved.

EFFECT OF 17α-METHYL-β-NORTESTOSTERONE (SK & F 7690) ON THE BINDING IN VITRO OF 5α-DIHYDROTESTOSTERONE TO MACROMOLECULAR COMPONENTS FROM THE RAT VENTRAL PROSTATE

1971 ◽  
Vol 66 (2) ◽  
pp. 352-356 ◽  
Author(s):  
Kjell J. Tveter
Keyword(s):  
Tissue Culture ◽  
Protein Complex ◽  
Incubation Medium ◽  
Culture Medium ◽  
Tissue Culture Medium ◽  
Male Rats ◽  
Ventral Prostate ◽  
Nuclear Fraction ◽  
Rat Ventral Prostate

ABSTRACT Slices from prostate glands of castrated male rats were incubated with [3H] 5α-dihydrotestosterone in Eagle's tissue culture medium. The labelled androgen was associated with androphilic macromolecules both in the prostatic cytosol and the nuclei. The addition of the anti-androgenic compound, 17α-methyl-β-nortestosterone (SK & F 7690) to the incubation medium inhibited the formation of the nuclear 5α-dihydrotestosterone-protein complex, and markedly reduced the cytosol 5α-dihydrotestosterone-protein complex. Likewise, the uptake of [3H] 5α-dihydrotestosterone by the prostatic nuclear fraction was reduced by about 40%.

STUDIES ON THE UPTAKE AND BINDING OF 5α-DIHYDROTESTOSTERONE BY RAT VENTRAL PROSTATE CELL NUCLEI IN VITRO

1970 ◽  
Vol 65 (3) ◽  
pp. 533-540 ◽  
Author(s):  
Olav Unhjem
Keyword(s):  
Sodium Chloride ◽  
Gel Filtration ◽  
Lower Degree ◽  
Ventral Prostate ◽  
Supernatant Fraction ◽  
Cell Nuclei ◽  
Gel Filtration Chromatography ◽  
Prostate Cell ◽  
Rat Ventral Prostate

ABSTRACT Following incubation of rat ventral prostate homogenates with 1,2-3H]-5α-dihydrotestosterone, the steroid was taken up and bound by the nuclei. Sodium chloride extraction of the nuclei removed macromolecules which might at least be partially responsible for the binding. Purified nuclei which were incubated with the radioactive steroid in either Tris-EDTA buffer or a 105 000 × g supernatant fraction prepared from the organ showed a lower degree of binding. Gel filtration chromatography of sodium chloride extracts from these nuclei disclosed binding of steroids to macromolecules. In all the experiments the steroids bound by nuclei consisted of unchanged 5α-dihydrotestosterone.

FURTHER STUDIES ON A SOLUBLE ANDROGEN-MACROMOLECULAR COMPLEX FROM THE RAT VENTRAL PROSTATE

1970 ◽  
Vol 65 (3) ◽  
pp. 517-524 ◽  
Author(s):  
Olav Unhjem
Keyword(s):  
Hydrogen Atom ◽  
Keto Group ◽  
Ventral Prostate ◽  
Metabolic Inhibitors ◽  
Macromolecular Complex ◽  
Structural Requirements ◽  
Macromolecular Complexes ◽  
Rat Ventral Prostate

ABSTRACT The ability of various steroids and metabolic inhibitors to influence the binding of androgen to soluble macromolecules in the rat ventral prostate was evaluated in vitro. The results obtained revealed some structural requirements of steroids for binding to the macromolecules. An androstane skeleton with the α-configuration of the hydrogen atom at position 5 seemed to be essential for binding as well as a keto group at position 3. N-ethylmaleimide, Na-iodoacetate and p-hydroxymercuribenzoate inhibited the binding of androgen to macromolecules. The androgen-macromolecular complexes appeared to be rather stable at temperatures below 5°C.

scholarly journals Incorporation of Testosterone and 5α-Dihydrotestosterone into Rat Ventral Prostate in vitro

1970 ◽  
Vol 17 (6) ◽  
pp. 453-458 ◽  
Author(s):  
JUN SHIMAZAKI ◽  
JIN SATO ◽  
HISAKO NAGAI ◽  
KEIZO SHIDA
Keyword(s):  
Ventral Prostate ◽  
Rat Ventral Prostate

Cell surface modifications in the epithelium of rat ventral prostate during adaptation to in vitro conditions: An ultrastructural study

In Vitro ◽  
1984 ◽  
Vol 20 (3) ◽  
pp. 216-228 ◽  
Author(s):  
Frederick B. Merk ◽  
Paul W. L. Kwan ◽  
Stanley Spilman ◽  
Louis Terracio ◽  
William H. J. Douglas
Keyword(s):  
Cell Surface ◽  
Ultrastructural Study ◽  
Surface Modifications ◽  
Ventral Prostate ◽  
Rat Ventral Prostate

Clinical studies of protein-bound calcium in various diseases.

1982 ◽  
Vol 28 (4) ◽  
pp. 672-675 ◽  
Author(s):  
P H Duncan ◽  
M R Wills ◽  
B J Smith ◽  
J Savory
Keyword(s):  
Multiple Myeloma ◽  
Liver Cirrhosis ◽  
Clinical Studies ◽  
Association Constant ◽  
Gel Filtration ◽  
The Other ◽  
Physiological Conditions ◽  
Essentially Normal ◽  
Filtration Technique

Abstract A recently developed gel-filtration technique allows protein-bound calcium fractions to be separated and quantitated; the protein is separated under physiological conditions of pH, temperature, and concentrations of Na, Mg, and Ca to assure that the calcium-proteinate equilibrium is not disturbed. We used this gel-filtration technique to study the protein-bound calcium fractions in 18 patients with hyperparathyroidism, multiple myeloma, diabetes, osteoporosis, or liver cirrhosis. We calculated the amount of calcium bound per gram of protein for each of the three protein peaks and the intrinsic association constant (Ka) for calcium/albumin. Results with the multiple myeloma patients (three IgG, one IgA) indicated that IgG did not bind calcium appreciably, that IgA had about the same affinity as albumin for Ca, and that Ka was slightly low for one patient of the IgG type (79 L/mol) and normal for the other three myeloma patients (106, 90, and 91 L/mol). Results for patients with the other diseases were also essentially normal, except for the osteoporesis patients (two men, one woman), whose Ka values (69, 75, and 73 L/mol) were lower than normal.

Sign in / Sign up

Export Citation Format

Share Document