EFFECTS OF CLOMIPHENE ON THE PHYSIOLOGY OF REPRODUCTION IN THE RAT

1964 ◽  
Vol 47 (4) ◽  
pp. 657-668 ◽  
Author(s):  
Somnath Roy ◽  
Robert B. Greenblatt ◽  
Virendra B. Mahesh
Keyword(s):  
Mode Of Action ◽  
Induction Of Ovulation ◽  
Receptor Sites

ABSTRACT The oestrogenic and antioestrogenic actions of clomiphene were studied in rats. In the absence of oestrogen in ovariectomized animals it exerted a uterotrophic effect, whereas, in the presence of a natural oestrogen (oestradiol) this compound at the same dosage levels counteracted the uterotrophic effect of the oestrogen. In suitable doses clomiphene also counteracted the gonadotrophin suppressing and ovulation-inhibiting actions of oestradiol. The results suggest that this agent may act by competing with the natural oestrogen for the receptor sites. The possible significance of these observations to the mode of action of clomiphene in the induction of ovulation in anovulatory women is discussed.

EFFECTS OF CLOMIPHENE ON THE PHYSIOLOGY OF REPRODUCTION IN THE RAT

1964 ◽  
Vol 47 (4) ◽  
pp. 669-675 ◽  
Author(s):  
Somnath Roy ◽  
Virendra B. Mahesh ◽  
Robert B. Greenblatt
Keyword(s):  
Pituitary Gland ◽  
Induction Of Ovulation ◽  
Receptor Sites ◽  
Immature Rats

ABSTRACT The uptake of intravenously administered tritiated oestradiol by the uterus and pituitary gland of untreated, as well as clomiphene pretreated immature rats was studied to elucidate the nature of the antioestrogenic action of clomiphene. The results indicate that this agent competes with the natural oestrogen for the receptor sites in the uterus and pituitary gland and prevents the entry of oestrogen to and probably displaces it from the receptor sites. The significance of these observations with respect to the ability of clomiphene for the induction of ovulation in anovulatory women is discussed.

OESTROGEN – ANTI-OESTROGEN INTERACTION: EFFECT OF U11100A, MRL-41 (CLOMIPHENE) AND U11555A ON OESTROGEN INDUCED UTERINE GLYCOGEN AND PROTEIN SYNTHESIS IN THE RAT DURING DELAYED IMPLANTATION

1969 ◽  
Vol 62 (3) ◽  
pp. 489-497 ◽  
Author(s):  
Suresh Mohla ◽  
M. R. N. Prasad
Keyword(s):  
Protein Synthesis ◽  
Comparative Study ◽  
Interaction Effect ◽  
Mode Of Action ◽  
Biochemical Changes ◽  
Delayed Implantation ◽  
Receptor Sites ◽  
Made In

ABSTRACT A comparative study of three non-steroidal anti-oestrogens (a dihydronaphthalene, UlllOOA; a diphenylindene derivative, U-11555A and MRL-41 (clomiphene) was made in order to study their mode of action and their interaction with oestrogen induced biochemical changes in the uterus. Pretreatment with UlllOOA, clomiphene or U11555A effectively blocked the oestrogen induced increase in uterine glycogen and protein synthesis. However, all the three compounds tested were found to be uterotrophic; clomiphene also increased uterine glycogen while U11555A showed a transient oestrogenic action in increasing uterine protein. Clomiphene and U11100A have been shown to inhibit the uptake of oestrogen at the receptor sites. Our results may be interpreted as indicating that pretreatment with these compounds (U11100A, clomiphene or U11555A) blocked the uterine receptor sites in such a manner so as to render ineffective the action of oestrogen administered subsequently.

THE UPTAKE OF LOCALLY APPLIED [6:7-3H]OESTRADIOL-17β BY THE VAGINA OF THE OVARIECTOMIZED MOUSE

1964 ◽  
Vol 30 (3) ◽  
pp. 337-346 ◽  
Author(s):  
L. MARTIN
Keyword(s):  
Biological Activity ◽  
Mode Of Action ◽  
Common Site ◽  
Tissue Levels ◽  
Ovariectomized Mouse ◽  
Receptor Sites ◽  
Site Of Action

SUMMARY Locally applied [6:7-3H]oestradiol was taken up rapidly by the vagina, at a rate similar to that of oestrone. Levels of radioactivity in the tissue reached their highest value 1–3 min. after application, and thereafter dropped slowly to reach 20% of the injected dose at 12 hr. This is in contrast to the behaviour of oestrone, the tissue levels of which fell rapidly over the first ½ hr. It is suggested that this difference accounts for the relative biological activity of the two hormones in the vagina, and results from varying affinities for receptor sites associated with the initiation of vaginal growth. Evidence is presented that oestrone, oestradiol and oestriol have a common site of action. Dimethylstilboestrol (DMS) converted the retention pattern of oestradiol to one resembling that of oestrone, and it is suggested that this involves blocking of receptor sites. The results are discussed in relation to the mode of action of oestrogens.

Clomiphene Citrate: Further Observations on its Use in Induction of Ovulation in the Human and on its Mode of Action

1963 ◽  
Vol 14 (6) ◽  
pp. 575-595 ◽  
Author(s):  
Somnath Roy ◽  
Robert B. Greenblatt ◽  
Virendra B. Mahesh ◽  
Edwin C. Jungck
Keyword(s):  
Mode Of Action ◽  
Clomiphene Citrate ◽  
Induction Of Ovulation

Induction of Ovulation with Sexovid (Compound F6066) and its Mode of Action

1969 ◽  
Vol 20 (6) ◽  
pp. 965-974 ◽  
Author(s):  
Tsunrharu Sato ◽  
Yoshito Ibuki ◽  
Masahira Hirono ◽  
Masao Igarashi ◽  
Seiichi Matsumoto
Keyword(s):  
Mode Of Action ◽  
Induction Of Ovulation

Effects of 5-5'-Diphenyl-2-thiohydantoin (DPTH) and Thyroxine on the Ultrastructure and Chemical Composition of Rat Liver

1971 ◽  
Vol 29 ◽  
pp. 570-571
Author(s):  
E. A. Elfont ◽  
R. B. Tobin ◽  
D. G. Colton ◽  
M. A. Mehlman
Keyword(s):  
Chemical Composition ◽  
Rat Liver ◽  
Future Study ◽  
Mode Of Action ◽  
Liver Mitochondria ◽  
Rat Liver Mitochondria ◽  
Effective Inhibitor ◽  
Biochemical Effects ◽  
Glycerophosphate Dehydrogenase ◽  
Stimulation Of

Summary5,-5'-diphenyl-2-thiohydantoin (DPTH) is an effective inhibitor of thyroxine (T4) stimulation of α-glycerophosphate dehydrogenase in rat liver mitochondria. Because this finding indicated a possible tool for future study of the mode of action of thyroxine, the ultrastructural and biochemical effects of DPTH and/or thyroxine on rat liver mere investigated.Rats were fed either standard or DPTH (0.06%) diet for 30 days before T4 (250 ug/kg/day) was injected. Injection of T4 occurred daily for 10 days prior to sacrifice. After removal of the liver and kidneys, part of the tissue was frozen at -50°C for later biocheailcal analyses, while the rest was prefixed in buffered 3.5X glutaraldehyde (390 mOs) and post-fixed in buffered 1Z OsO4 (376 mOs). Tissues were embedded in Araldlte 502 and the sections examined in a Zeiss EM 9S.Hepatocytes from hyperthyroid rats (Fig. 2) demonstrated enlarged and more numerous mitochondria than those of controls (Fig. 1). Glycogen was almost totally absent from the cytoplasm of the T4-treated rats.

Sites of Adsorption of the Bacteriophages T3 and T5 on the Wall of Escherichia Coli B.

1967 ◽  
Vol 25 ◽  
pp. 96-97
Author(s):  
Manfred E. Bayer
Keyword(s):  
Escherichia Coli ◽  
Cell Wall ◽  
Electron Microscope ◽  
Uranyl Acetate ◽  
E Coli ◽  
Receptor Sites ◽  
Rigid Cell Wall ◽  
Host Cell Surface ◽  
Bacterial Viruses ◽  
Escherichia Coli B

Bacterial viruses adsorb specifically to receptors on the host cell surface. Although the chemical composition of some of the cell wall receptors for bacteriophages of the T-series has been described and the number of receptor sites has been estimated to be 150 to 300 per E. coli cell, the localization of the sites on the bacterial wall has been unknown.When logarithmically growing cells of E. coli are transferred into a medium containing 20% sucrose, the cells plasmolize: the protoplast shrinks and becomes separated from the somewhat rigid cell wall. When these cells are fixed in 8% Formaldehyde, post-fixed in OsO4/uranyl acetate, embedded in Vestopal W, then cut in an ultramicrotome and observed with the electron microscope, the separation of protoplast and wall becomes clearly visible, (Fig. 1, 2). At a number of locations however, the protoplasmic membrane adheres to the wall even under the considerable pull of the shrinking protoplast. Thus numerous connecting bridges are maintained between protoplast and cell wall. Estimations of the total number of such wall/membrane associations yield a number of about 300 per cell.

Activation of Hageman Factor by α-Adrenergic Stimulation

1970 ◽  
Vol 23 (03) ◽  
pp. 417-422 ◽  
Author(s):  
D. G McKay ◽  
J.-G Latour ◽  
Mary H. Parrish
Keyword(s):  
Disseminated Intravascular Coagulation ◽  
Adrenergic Receptor ◽  
Adrenergic Stimulation ◽  
Hageman Factor ◽  
Intravascular Coagulation ◽  
Receptor Sites ◽  
High Doses ◽  
Stimulation Of

SummaryThe infusion of epinephrine in high doses produces disseminated intravascular coagulation by activation of Hageman factor. The effect is blocked by phenoxybenz-amine and is therefore due to stimulation of α-adrenergic receptor sites.

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