scholarly journals Uterine oestrogen-receptor binding to oligo(dT)-cellulose. An inhibitor from hypothalamic cytosol

1979 ◽  
Vol 182 (1) ◽  
pp. 241-243 ◽  
Author(s):  
G Shen ◽  
S Thrower ◽  
L Lim
Keyword(s):  
Receptor Binding ◽  
Oestrogen Receptor ◽  
Potent Inhibitor

The binding of rat uterine cytosol oestrogen receptor in vitro to oligo(dT)-cellulose is mediated by an activating factor in the cytosol [Thrower, Hall, Lim & Davison (1976) Biochem. J. 160, 271-280]. A potent inhibitor of this binding is present in hypothalamic cytosol. This inhibitor may have a role in vivo in regulating receptor translocation in the hypothalamus.

scholarly journals CHIR-124, a Novel Potent Inhibitor of Chk1, Potentiates the Cytotoxicity of Topoisomerase I Poisons In vitro and In vivo

2007 ◽  
Vol 13 (2) ◽  
pp. 591-602 ◽  
Author(s):  
Archie N. Tse ◽  
Katherine G. Rendahl ◽  
Tahir Sheikh ◽  
Haider Cheema ◽  
Kim Aardalen ◽  
...  
Keyword(s):  
Topoisomerase I ◽  
Potent Inhibitor

A highly potent inhibitor of cathepsin K (relacatib) reduces biomarkers of bone resorption both in vitro and in an acute model of elevated bone turnover in vivo in monkeys

Bone ◽  
2007 ◽  
Vol 40 (1) ◽  
pp. 122-131 ◽  
Author(s):  
S. Kumar ◽  
L. Dare ◽  
J.A. Vasko-Moser ◽  
I.E. James ◽  
S.M. Blake ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Bone Turnover ◽  
Potent Inhibitor ◽  
Cathepsin K

Thyroid hormone modulates androgen and oestrogen receptor content in the Sertoli cells of peripubertal rats

1996 ◽  
Vol 148 (1) ◽  
pp. 43-50 ◽  
Author(s):  
M L Panno ◽  
D Sisci ◽  
M Salerno ◽  
M Lanzino ◽  
V Pezzi ◽  
...  
Keyword(s):  
Sertoli Cells ◽  
Oestrogen Receptor ◽  
Age Groups ◽  
Strong Relationship ◽  
Inhibitory Influence ◽  
Aromatase Activity ◽  
Severe Impairment ◽  
Cellular Compartments

Abstract A possible role of tri-iodothyronine (T3) on the interplay between testicular steroids and Sertoli cells has been investigated on the basis of previous findings demonstrating a direct inhibitory influence of T3 on aromatase activity and oestradiol production in peripuberal Sertoli cells. In this context, the present study was focused on the effects of T3 on oestrogen receptor (ER) and androgen receptor (AR) contents in the cytosol and nucleus of Sertoli cells isolated from 2-, 3- and 4-week-old euthyroid, hypothyroid and hypothyroid treated rats. Hypothyroidism was induced by the oral administration of 0·025% methimazole (MMI) from birth until the rats were killed at 2, 3 and 4 weeks of age. Half of the MMI-treated animals were injected i.p. with l-tri-iodothyronine (T3; 3 μg/100 g body weight) during the last week before death. Sertoli cells from all groups were initially cultured under basal conditions for the first 24 h and subsequently in the presence of testosterone with or without T3 for an additional 24 h. Hypothyroidism was associated with severe impairment of body as well as testicular growth. Euthyroid ERs showed an elevated Kd (0·76 nm) which was similar in the different age groups investigated. The in vitro addition of T3 or testosterone induced a decrease in ER content and this decrease was greater after exposure to both hormones. In 2- and 3-week-old hypothyroid rats, ER content was markedly increased and was reversed in euthyroid rats when T3 was given in vivo. When ERs were assayed in the Sertoli cell nucleus and cytoplasm of 2- and 3-week-old animals, a strong relationship in ER content in the two cellular compartments was observed. Neither of the hormones tested seemed to affect the AR content in the nucleus significantly, while the in vitro addition of testosterone or T3 or both hormones together augmented the ARs in the cytosol to a greater extent, resulting in an increase in their total (cytosolic and nuclear) content in the cells. The present data suggest that T3 down-regulates ERs and up-regulates ARs in peripuberal Sertoli cells. The additive effect of testosterone and T3 in up-regulating ARs could possibly involve a role for T3 in influencing the androgen responsiveness of the Sertoli cells during spermatogenesis. Journal of Endocrinology (1996) 148, 43–50

In vitro and in vivo receptor binding and deoxyglucose studies in rat brain with the potential antipsychotic Org 5222

1990 ◽  
Vol 183 (5) ◽  
pp. 1623
Author(s):  
J.A.D.M. Tonnaer ◽  
P. Room ◽  
W.M.J.B. Van Gemert ◽  
L.P.C. Delbressine ◽  
T. de Boer ◽  
...  
Keyword(s):  
Rat Brain ◽  
Receptor Binding ◽  
In Vivo Receptor Binding

CATECHOL OESTROGENS AND GONADOTROPHIN SECRETION IN THE EWE: AFFINITY FOR PITUITARY OESTROGEN RECEPTORS IN VITRO AND ACTION ON GONADOTROPHIN SECRETION IN VIVO

1980 ◽  
Vol 85 (3) ◽  
pp. 503-509 ◽  
Author(s):  
I. J. CLARKE ◽  
J. K. FINDLAY
Keyword(s):  
Negative Feedback ◽  
Oestrogen Receptor ◽  
Dose Response Relationship ◽  
Concurrent Administration ◽  
Feedback Effects ◽  
Dependent Relationship ◽  
Gonadotrophin Secretion ◽  
Dose Dependent

The binding of three catechol oestrogens, 2-OH-oestradiol-17β, 4-OH-oestrone and 2-OH-oestrone, to the ovine pituitary oestrogen receptor was measured in vitro to establish doses for the assessment of the effects of catechol oestrogens in vivo. Relative to oestradiol (100%) the compounds had receptor affinities of 30, 20 and 5% respectively. A dose of oestradiol sufficient to cause negative-feedback effects on the secretion of LH and FSH in ovariectomized ewes was established by intracarotid (i.c.) injections of 0·625–5·0 μg/dose (n = 3), and by measuring plasma levels of gonadotrophins in jugular venous samples taken at intervals of 20 min from 3 h before until 4 h after injection. A dose-dependent relationship (r = 0·88, P<0·001) was found for oestradiol and plasma LH levels. Plasma FSH was slightly (12–25%) but significantly (P<0·05) reduced by doses of 1·25–5·0 μg oestradiol, but no dose–response relationship was observed. Ovariectomized ewes (n = 4/group) were given 2·5 μg oestradiol (i.c.) simultaneously with 83 μg 2-OH-oestradiol, 125 μg 4-OH-oestrone or 500 μg 2-OH-oestrone. These doses of catechol oestrogens were chosen as being ten times that of oestradiol, with the relative affinities for oestrogen receptor taken into account. Concurrent administration of such doses of catechol oestrogens had no effect on the negative-feedback action of oestradiol in vivo. We have concluded that catechol oestrogens in the circulation probably do not modulate the action of oestradiol on release of LH or FSH; this does not preclude a possible role for them as locally produced regulators of oestrogen action.

A comparison of in vivo and in vitro neuroimaging of 5-HT1A receptor binding sites in the cat brain

2006 ◽  
Vol 31 (3) ◽  
pp. 226-232 ◽  
Author(s):  
Nicolas Aznavour ◽  
Latifa Rbah ◽  
Lucienne Léger ◽  
Colette Buda ◽  
Jean-Pierre Sastre ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Binding Sites ◽  
Cat Brain

scholarly journals Soluble Heparin and Heparan Sulfate Glycosaminoglycans Interfere with Sonic Hedgehog Solubilization and Receptor Binding

Molecules ◽  
2019 ◽  
Vol 24 (8) ◽  
pp. 1607 ◽  
Author(s):  
Manikowski ◽  
Jakobs ◽  
Jboor ◽  
Grobe
Keyword(s):  
Heparan Sulfate ◽  
Sonic Hedgehog ◽  
Receptor Binding ◽  
Feedback Loop ◽  
Cancer Cell Growth ◽  
Shh Signaling ◽  
Epithelial Cancers ◽  
And Function

Sonic hedgehog (Shh) signaling plays a tumor-promoting role in many epithelial cancers. Cancer cells produce soluble a Shh that signals to distant stromal cells that express the receptor Patched (Ptc). These receiving cells respond by producing other soluble factors that promote cancer cell growth, generating a positive feedback loop. To interfere with reinforced Shh signaling, we examined the potential of defined heparin and heparan sulfate (HS) polysaccharides to block Shh solubilization and Ptc receptor binding. We confirm in vitro and in vivo that proteolytic cleavage of the N-terminal Cardin–Weintraub (CW) amino acid motif is a prerequisite for Shh solubilization and function. Consistent with the established binding of soluble heparin or HS to the Shh CW target motif, both polysaccharides impaired proteolytic Shh processing and release from source cells. We also show that HS and heparin bind to, and block, another set of basic amino acids required for unimpaired Shh binding to Ptc receptors on receiving cells. Both modes of Shh activity downregulation depend more on HS size and overall charge than on specific HS sulfation modifications. We conclude that heparin oligosaccharide interference in the physiological roles of HS in Shh release and reception may be used to expand the field of investigation to pharmaceutical intervention of tumor-promoting Shh functions.

4-Methoxydalbergione is a potent inhibitor of human astroglioma U87 cells in vitro and in vivo

2020 ◽  
Author(s):  
Ran Li ◽  
Chang-qiong Xu ◽  
Jian-xin Shen ◽  
Qiu-yun Ren ◽  
Di-ling Chen ◽  
...  
Keyword(s):  
Potent Inhibitor ◽  
U87 Cells
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