scholarly journals High-affinity binding of oestradiol-17β by cytosols from testis interstitial tissue, pituitary, adrenal, liver and accessory sex glands of the male rat

1974 ◽  
Vol 140 (3) ◽  
pp. 495-502 ◽  
Author(s):  
Wilma M. O. Van Beurden-Lamers ◽  
Albert O. Brinkmann ◽  
Eppo Mulder ◽  
Henk J. Van Der Molen
Keyword(s):  
Binding Capacity ◽  
Gradient Centrifugation ◽  
Sedimentation Coefficient ◽  
Wide Distribution ◽  
Male Rat ◽  
Interstitial Tissue ◽  
Apparent Contradiction ◽  
High Affinity ◽  
Specific Receptors ◽  
Agar Gel Electrophoresis

The specificity of the binding of oestradiol-17β by cytoplasmic fractions of several tissues of the male rat was investigated. 1. Agar-gel electrophoresis, Sephadex chromatography, adsorption by dextran-coated charcoal and sucrose-gradient centrifugation were used to estimate the binding capacity and specificity. The four different methods all gave similar results for the capacity of the specific oestradiol-17β-binding macromolecules in the testis. 2. The presence of a specific saturable binding protein with a sedimentation coefficient of 8S was demonstrated in liver, adrenal, pituitary, prostate, epididymis and testis interstitial tissue. The highest concentration of oestradiol-17β-binding macromolecules was found in testis interstitial tissue (0.12pmol/mg of protein) and in the pituitary (0.075pmol/mg of protein). 3. The oestradiol-17β receptor in the testis cytosol showed the characteristics of a protein with respect to Pronase treatment and temperature sensitivity. In competition experiments with different steroids the receptor showed a high affinity for oestradiol-17β, a moderate affinity for diethylstilboestrol and oestradiol-17α and a low affinity for oestrone, oestriol, testosterone and 5α-dihydrotestosterone (17β-hydroxy-5α-androstan-3-one). 4. The wide distribution of oestradiol-17β receptors in the male rat is in apparent contradiction to the current concept of the specificity of steroid-hormone action. Further research is required to investigate a possible physiological meaning of the presence of specific receptors in the different tissues.

High affinity binding of oestradiol by rat testis interstitial tissue and by several other tissues of the male rat

1974 ◽  
Vol 5 (8) ◽  
pp. 955-959 ◽  
Author(s):  
E. Mulder ◽  
W.M.O. van Beurden-Lamers ◽  
A.O. Brinkmann ◽  
M.J. Mechielsen ◽  
H.J. van der Molen
Keyword(s):  
Male Rat ◽  
Interstitial Tissue ◽  
Affinity Binding ◽  
High Affinity Binding ◽  
Rat Testis ◽  
High Affinity

scholarly journals Hydrodynamic properties of adenosine Ri receptors solubilized from rat cerebral-cortical membranes

1987 ◽  
Vol 248 (3) ◽  
pp. 635-642 ◽  
Author(s):  
S M H Yeung ◽  
E Perez-Reyes ◽  
D M F Cooper
Keyword(s):  
Adenosine Receptor ◽  
Sucrose Gradient ◽  
Gradient Centrifugation ◽  
Gel Filtration ◽  
Sedimentation Coefficient ◽  
Guanine Nucleotides ◽  
Hydrodynamic Properties ◽  
High Affinity ◽  
Bivalent Cations ◽  
Cortical Membranes

Adenosine Ri receptors and inhibitory guanine-nucleotide-regulatory components were solubilized from rat cerebral-cortical membranes with sodium cholate. (-)-N6-Phenylisopropyl[2,8-3H]adenosine [(3H]PIA) binds with high affinity to the soluble receptors, which retain the pharmacological specificity of adenosine Ri receptors observed in membranes. The binding is regulated by bivalent cations and guanine nucleotides. Bivalent cations increase [3H]PIA binding by increasing both the affinity and the apparent number of receptors. Guanine nucleotides decrease agonist binding by increasing the dissociation of the ligand-receptor complex. Adenosine agonists stabilize the high-affinity form of the soluble receptor. The hydrodynamic properties of the adenosine receptor were determined with cholate extracts of membranes that were treated with [3H]PIA. Sucrose-gradient-centrifugation analysis indicates that the receptor has a sedimentation coefficient of 7.7 S. The receptor is eluted from Sepharose 6B columns with an apparent Stokes radius of 7.2 nm. Labelling of either sucrose-gradient or gel-filtration-column fractions with pertussis toxin and [32P]-NAD+ reveals that both the 41,000- and 39,000-Mr substrates overlap with the receptor activity. These studies suggest that the high-affinity adenosine-receptor-binding activity in the cholate extract represents a stable R1-N complex.

scholarly journals Specific vasopressin binding to rat adrenal glomerulosa cells. Relationship to inositol lipid breakdown

1986 ◽  
Vol 235 (1) ◽  
pp. 209-214 ◽  
Author(s):  
G Guillon ◽  
N Gallo-Payet
Keyword(s):  
Inositol Phosphate ◽  
Binding Capacity ◽  
Free Ligand ◽  
Zona Glomerulosa ◽  
High Affinity ◽  
Rat Adrenals ◽  
Vasopressin Receptors ◽  
Inositol Phosphate Accumulation ◽  
Specific Receptors ◽  
Glomerulosa Cells

Cells from the zona glomerulosa of rat adrenals were isolated and maintained for 3 days in primary culture. Specific vasopressin binding was determined by using [3H]vasopressin. [3H]Vasopressin binding was time-dependent (half-time of about 2 min for 6 nM free ligand) and reversible on addition of unlabelled vasopressin (80% dissociation within 30 min). Dose-dependent [3H]vasopressin binding at equilibrium indicated that vasopressin interacted with two populations of sites: high-affinity sites (dissociation constant, Kd = 1.8 nM; maximal binding capacity = 10 fmol/10(6) cells) and low-affinity sites. Vasopressin increased the cellular content of labelled inositol mono-, bis- and tris-phosphate in cells prelabelled with myo-[3H]inositol. The vasopressin concentration eliciting half-maximal inositol phosphate accumulation was very close to the Kd value for vasopressin binding to high-affinity sites. Competition experiments using agonists and antagonists with enhanced selectivity for previously characterized vasopressin receptors indicated that vasopressin receptors from rat glomerulosa cells are V1 receptors of the vascular or hepatic subtype. The detected specific vasopressin-binding sites might represent the specific receptors mediating the mitogenic and steroidogenic effects of vasopressin on glomerulosa cells from rat adrenals.

Cytoplasmic progesterone receptors in uterine tissue of the snapping turtle (Chelydra serpentina)

1986 ◽  
Vol 109 (3) ◽  
pp. 385-392 ◽  
Author(s):  
I. Y. Mahmoud ◽  
A. E. Colás ◽  
M. J. Woller ◽  
R. V. Cyrus
Keyword(s):  
Binding Sites ◽  
Gradient Centrifugation ◽  
Linear Regression Analysis ◽  
Deae Cellulose ◽  
Sedimentation Coefficient ◽  
Ovarian Follicles ◽  
Corpora Lutea ◽  
Chelydra Serpentina ◽  
Snapping Turtle ◽  
High Affinity

ABSTRACT A high affinity progesterone-binding component was detected in the cytosol of the uterus of the snapping turtle, Chelydra serpentina. Density gradient centrifugation indicated that binding of [3H]progesterone and [3H]promegestone (R5020) was to a fraction with a heavier sedimentation coefficient than bovine serum albumin (BSA) appearing as a broader peak in the 6–7 S region; it was not affected by excess cortisol. Another binding peak, lighter than BSA and appearing with [3H]R5020 and [3H]progesterone near the 4 S region, was affected by excess cortisol. Excess progesterone decreased both the heavier and lighter peaks. Analysis of steroid specificity revealed that, of the natural steroids, progesterone had the highest affinity for the uterine cytosol. This was followed by deoxycorticosterone, 5α-pregnanedione, testosterone, oestradiol-17β, corticosterone, 5α-dihydrotestosterone and cortisol. Non-linear regression analysis of saturation data indicated the presence of two classes of high affinity binding sites: progesterone-binding sites (R-sites) with equilibrium association constants (Ka) of 2·9 ± 0·28 litres/nmol (mean ± 95% confidence limit) for [3H]R5020 and 0·34 ± 0·20 litres/nmol for [3H]progesterone, and corticosteroid-binding globulin-like sites (G-sites) with Ka of 4·5 ± 1·6 litres/nmol for progesterone. The concentration of R-sites was between 0·66 ± 0·10 and 2·6 ± 0·55 pmol/mg protein while that of G-sites was between 0·73 ± 0·05 and 5·0 ± 0·27 pmol/mg protein. DEAE-cellulose filtration assay also confirmed the presence of R-sites and G-sites in the cytosol. R-sites were detectable without oestrogen priming during the preovulatory and vitellogenic phases (low progesterone, high oestrogen concentrations) when the ovarian follicles are mature (18–22 mm diameter). During the early postovulatory phase (high progesterone, low oestrogen concentrations), when the ovarian follicles are immature (5–7 mm diameter) and active corpora lutea are present, the R-sites were undetectable even after oestrogen priming. This indicates that progesterone might have an inhibitory and oestrogen a stimulatory role in the regulation of R-sites. J. Endocr. (1986) 109, 385–392

DEMONSTRATION OF A SPECIFIC CYTOSOL RECEPTOR IN THE NORMAL AND HYPERPLASTIC CANINE PROSTATE FOR 5α-ANDROSTANE-3α, 17α-DIOL

1975 ◽  
Vol 64 (3) ◽  
pp. 539-548 ◽  
Author(s):  
C. R. EVANS ◽  
C. G. PIERREPOINT
Keyword(s):  
Sucrose Gradient ◽  
Gradient Centrifugation ◽  
Sedimentation Coefficient ◽  
Receptor Protein ◽  
Specific Receptor ◽  
Receptor Molecule ◽  
Sucrose Gradient Centrifugation ◽  
High Affinity

SUMMARY A specific receptor protein has been demonstrated for 5α-androstane-3α, 17α-diol in cytoplasmic extracts of normal and hyperplastic canine prostates. The receptor molecule, with a sedimentation coefficient of 4–5S, has been identified by the use of sucrose gradient centrifugation of tissue fractions which had been labelled in vitro with tritiated 5α-androstane-3α, 17α-diol. The receptor showed a relatively high affinity for this compound whereas binding could not be demonstrated with other labelled C19 steroids. In addition binding of tritiated 5α-androstane-3α, 17α-diol was not affected by the presence of 50-fold excesses of other C19 steroids.

Cholecystokinin receptors

1995 ◽  
Vol 269 (5) ◽  
pp. G628-G646 ◽  
Author(s):  
S. A. Wank
Keyword(s):  
Function Analysis ◽  
Receptor Gene ◽  
Wide Distribution ◽  
Receptor Expression ◽  
Receptor Subtypes ◽  
Cck Receptors ◽  
High Affinity ◽  
Recombinant Receptor ◽  
Receptor Pharmacology ◽  
Specific Variation

The cholecystokinin (CCK) and gastrin families of peptides act as hormones and neuropeptides on central and peripheral CCK receptors to mediate secretion and motility in the gastrointestinal (GI) tract in the physiological response to a normal meal. CCK and its receptors are also widely distributed in the central nervous system (CNS) and contribute to the regulation of satiety, anxiety, analgesia, and dopamine-mediated behavior. Although the wide distribution, myriad number of functions, and reported pharmacological heterogeneity of CCK receptors would suggest a large number of receptor subtypes, the application of modern molecular biological techniques has identified two CCK receptors, CCK-A receptor (CCK-AR) and CCK-B receptor (CCK-BR), that mediate the actions of CCK and gastrin; gastrin receptors have been found to be identical to CCK-BR. CCK-AR, found predominantly in the GI system and select areas of the CNS, have high affinity for CCK and the nonpeptide antagonist L-364,718, whereas CCK-BR, found predominantly in the CNS and select areas of the GI system, have high affinity for CCK and gastrin and the nonpeptide antagonist L-365,260. Both CCK-AR and CCK-BR are highly conserved between species, although there is some tissue-specific variation in expression. Recombinant receptor expression faithfully reproduces the native receptor pharmacology and signal transduction pathways, allowing direct comparisons of receptor function between species as well as serving as a convenient source of receptor. Our present knowledge of the chromosomal localization, receptor gene structure, and primary sequence will allow further studies in disease association, receptor regulation, and structure-function analysis.

The Temporal Distribution of the 1α,25-Dihydroxycholecalciferol Receptor in the Rat Jejunal Villus

1984 ◽  
Vol 67 (3) ◽  
pp. 285-290 ◽  
Author(s):  
S. D. H. Chan ◽  
D. Atkins
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Calcium Absorption ◽  
Sedimentation Coefficient ◽  
Temporal Distribution ◽  
High Affinity ◽  
High Affinity Receptor ◽  
Affinity Receptor ◽  
Cell Fractions ◽  
Crypt Cells

1. The distribution of the 1α,25-dihydroxycholecalciferol receptor was studied in enterocytes isolated from the upper, mid and lower villus and crypt cells of the jejunum of normal and rachitic rats. 2. In all cell fractions a high-affinity receptor (KD ⋍ 0.07 nmol/l) with a sedimentation coefficient of 3.5S was demonstrated. 3. In normal rats there was a 60% reduction in receptor numbers in crypt cells compared with the mid and upper villous cells. 4. Vitamin D deficiency led to a reduction in receptor numbers in all cell fractions (45% upper villus, 78% crypt cells). 5. The data are compatible with the concept of calcium absorption occurring in the differentiated villous cells and also account for the reduction in absorption in rachitic animals.

Progestin receptors in prolactin and growth hormone producing tumours in rats

1982 ◽  
Vol 100 (1) ◽  
pp. 25-30 ◽  
Author(s):  
Oddvar Naess ◽  
Egil Haug ◽  
Arne Attramadal ◽  
Kaare M. Gautvik
Keyword(s):  
Growth Hormone ◽  
Glucocorticoid Receptors ◽  
Progesterone Receptors ◽  
Pituitary Tumour ◽  
Tumour Cells ◽  
Female Rats ◽  
Progestin Receptors ◽  
High Affinity ◽  
Protein Nature ◽  
Specific Receptors

Abstract. Progesterone and corticosterone have a similar effect on the production of growth hormone (GH) and prolactin (Prl) by pituitary tumour cells (GH3 cells) in culture. Previously we have shown that progesterone has a high affinity for the glucocorticoid receptors in these cells. Progesterone may therefore exert its effects through binding to the glucocorticoid receptor. The aim of the present study was to investigate if the GH3 tumour cells and an oestrogen induced pituitary tumour, which also produce GH and Prl, possess specific receptors for progesterone. Both the GH3 tumours and the oestrogen induced pituitary tumour were in fact found to possess cytoplasmatic receptor molecules for progesterone by using the potent progestin R5020 as a marker. Isoelectric focusing revealed one binding component (pH 5.9), which was of protein nature. The binding was of high affinity (Kd 2 × 10−9 mol/l). In the oestrogen induced tumour, the maximal binding was 70 fmol/mg cytosol protein. In female rats with GH3 tumours the binding was 55 fmol/mg cytosol protein. Priming of the animals with 1 mg oestradiol-valerate increased the binding to 116 fmol/mg cytosol protein, whereas very little binding was found in GH3 tumours from rats castrated 7 days before sacrifice. The receptors in the oestrogen induced pituitary tumour and the GH3 tumours exhibited high affinity for R5020 and progesterone, whereas corticosterone had no significant affinity for the receptors. Using exchange assay, it was demonstrated that the cytoplasmic progestin receptors could be translocated to the nucleus after administration of progesterone to the animals. Thus, the presence of specific progesterone receptors, different from the glucocorticoid receptors, strongly indicates that the effects of progesterone on GH and Prl production are mediated through the progesterone receptors.

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