THE UPTAKE OF 17β-OESTRADIOL IN BREAST TISSUE OF FEMALE RATS

1968 ◽  
Vol 58 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Sten Sander
Keyword(s):  
Skeletal Muscle ◽  
Direct Effect ◽  
Breast Tissue ◽  
The Other ◽  
Female Rats ◽  
Competitive Effect ◽  
Simultaneous Injection ◽  
Other Hand ◽  
Uptake Pattern ◽  
Wet Weight

ABSTRACT The uptake of radioactivity in breast tissue after the injection of tritiated oestradiol in rats has been studied. The breast tissue accumulates more radioactivity per unit wet weight than skeletal muscle and fat, for at least 4 hours. The uptake of radioactivity does not, however, reach the high levels observed in the uterus. On the other hand, the uptake pattern found in the breast tissue corresponds to previous findings in other oestrogen responsive organs. The uptake of radioactivity by breast tissue in castrated rats is higher than in control animals with their ovaries intact. It is also found that simultaneous injection of non-radioactive oestradiol reduces the uptake of radioactivity. These findings may be explained as a competitive effect between non-labelled and labelled oestradiol. The accumulation of oestradiol observed may be consistent with the idea of a direct effect on breast tissue.

Regrowth of atrophied skeletal muscle in adult rats after ending immobilization

1978 ◽  
Vol 44 (2) ◽  
pp. 225-230 ◽  
Author(s):  
F. W. Booth
Keyword(s):  
Skeletal Muscle ◽  
Body Weight ◽  
Adult Female ◽  
Total Protein ◽  
Recovery Time ◽  
Time Course ◽  
Citrate Synthase ◽  
Female Rats ◽  
Adult Rats ◽  
Wet Weight

The recovery time course of muscle atrophied by immobilization was followed after removal of hindlimb casts from adult female rats. Increases of only 9% in body weight, 4% in gastrocnemius weight, and 10% in soleus weight occurred in controls during the 78-day duration of the experiment. There were no increases in the amounts of total protein or of citrate synthase activities in gastrocnemius or soleus during the first 3 days after removal of hindlimb casts; thereafter, there were increases in these paramters. Citrate synthase activities per mg of gastrocnemius protein were significantly higher at the 16th and 50th day of recovery. No significant differences for citrate synthase activity per mg of soleus occurred during recovery. Until the 50th day of recovery, no significant differences for total protein in soleus and for total protein and wet weight of gastrocnemius were observed between control and recovery values. However, the wet weight of the soleus returned rapidly during recovery and was not significantly different from control during recovery.

scholarly journals Predominant androgenic component in the stimulatory effect of dehydroepiandrosterone on bone mineral density in the rat

1998 ◽  
Vol 157 (3) ◽  
pp. 433-442 ◽  
Author(s):  
C Martel ◽  
A Sourla ◽  
G Pelletier ◽  
C Labrie ◽  
M Fournier ◽  
...  
Keyword(s):  
Trabecular Bone ◽  
Bone Mineral ◽  
Bone Volume ◽  
The Other ◽  
Female Rats ◽  
Trabecular Bone Volume ◽  
A Value ◽  
Other Hand ◽  
Dhea Treatment ◽  
Trabecular Number

In order to assess the relative roles of the androgenic and/or estrogenic components in the stimulatory effect of dehydroepiandrosterone (DHEA) on bone mineral content (BMC) and density (BMD), ovariectomized (OVX) female rats received DHEA administered alone or in combination with the antiandrogen flutamide (FLU) or the antiestrogen EM-800 for 12 months. We also evaluated, for comparison, the effect of estradiol (E2) and dihydrotestosterone (DHT) constantly released by Silastic implants as well as medroxyprogesterone acetate (MPA) released from poly(lactide-co-glycolide) microspheres. Femoral BMD was decreased by 11% 1 year after OVX, but treatment of OVX animals with DHEA increased BMD to a value 8% above that of intact animals. The administration of FLU reversed by 76% the stimulatory effect of DHEA on femoral BMD and completely prevented the stimulatory effect of DHEA on total body and lumbar spine BMD. Similar results were obtained for BMC. On the other hand, treatment with the antiestrogen EM-800 did not reduce the action of DHEA on BMD or BMC. At the doses used, MPA, E2 and DHT increased femoral BMD, but to a lesser degree than observed with DHEA. Bone histomorphometry measurements were also performed. While DHEA treatment partially reversed the marked inhibitory effect of OVX on the tibial trabecular bone volume, the administration of FLU inhibited by 51% (P < 0.01) the stimulatory effect of DHEA on this parameter. The addition of EM-800 to DHEA, on the other hand, increased trabecular bone volume to a value similar to that of intact controls. DHEA administration markedly increased trabecular number while causing a marked decrease in the intertrabecular area. The above stimulatory effect of DHEA on trabecular number was reversed by 54% (P < 0.01) by the administration of FLU, which also reversed by 29% the decrease in intertrabecular area caused by DHEA administration. On the other hand, the addition of EM-800, while further decreasing the intertrabecular space achieved by DHEA treatment, also led to a further increase in trabecular number to a value not significantly different from that of intact control animals, suggesting an additional effect of EM-800 over that achieved by DHEA. Treatment with DHEA caused a 4-fold stimulation of serum alkaline phosphatase, a marker of bone formation, while the urinary excretion of hydroxyproline, a marker of bone resorption, was decreased by DHEA treatment. Treatment with DHEA and DHEA + EM-800 decreased serum cholesterol levels by 22 and 65% respectively, while the other treatments had no significant effect on this parameter. The present data indicate that the potent stimulatory effect of DHEA on bone in the rat is mainly due to the local formation of androgens in bone cells and their intracrine action in osteoblasts.

CORTISOLWIRKUNGEN AUF DEN PROTEINUND ENERGIESTOFFWECHSEL IN DER PERIPHERIE

1968 ◽  
Vol 59 (2) ◽  
pp. 193-202
Author(s):  
H. Kröner ◽  
W. Staib
Keyword(s):  
Skeletal Muscle ◽  
Protein Synthesis ◽  
Energy Consumption ◽  
Connective Tissue ◽  
Oxidative Metabolism ◽  
The Other ◽  
Other Hand ◽  
Inhibition Of Protein Synthesis ◽  
Short Time ◽  
Rna And Dna

ABSTRACT By measuring protein, RNA and DNA in skeletal muscle and spleen we were unable to demonstrate an enhanced catabolism due to cortisol. On the other hand we could demonstrate a reduced anabolism by diminished incorporation of 14C labelled leucin in protein of muscle, spleen and skin. Simultaneously an increase of ATP and an equivalent decrease of ADP were found in connective tissue, which were regarded as a consequence of reduced energy consumption. In skeletal muscle a decrease of energy consumption due to cortisol was only indirect demonstrable by reduced glycolysis when oxidative metabolism was eliminated for a short time. It seems obvious, that inhibition of protein synthesis causes the diminished energy consumption.

Capillary Diffusion Distances - Their Importance for Cardiac and Skeletal Muscle Performance

Physiology ◽  
1988 ◽  
Vol 3 (4) ◽  
pp. 134-138 ◽  
Author(s):  
O Hudlicka ◽  
S Egginton ◽  
MD Brown
Keyword(s):  
Skeletal Muscle ◽  
Oxygen Delivery ◽  
The Other ◽  
Muscle Performance ◽  
Important Indicator ◽  
Capillary Supply ◽  
Other Hand ◽  
Potential Oxygen ◽  
Skeletal Muscle Performance

Intercapillary distances are considered an important indicator of oxygen delivery to tissue. In this article, various indices of capillary supply to cardiac and skeletal muscle are related to the performance of the same organ. It becomes apparent that there are several situations in which maximal muscle performance is not improved, although intercapillary distances are shortened, implying greater potential oxygen delivery. On the other hand, there are also cases where performance is improved without any change in capillary supply.

From 'Ā'esha to Nur Jahān: The Shaping of a Classical Persian Poetic Canon of Women

2009 ◽  
Vol 2 (2) ◽  
pp. 148-164 ◽  
Author(s):  
Sunil Sharma
Keyword(s):  
Eighteenth Century ◽  
Direct Effect ◽  
Literary History ◽  
Literary Tradition ◽  
The Other ◽  
Women Poets ◽  
Cultural Shift ◽  
Other Hand ◽  
The One ◽  
The Way

AbstractThe eighteenth century witnessed an interest in Persian women poets and attempts were made by writers of tazkeras to create a female canon of poets. The cultural shift in the Iranian-Indian interface at this time had a direct effect on the writing of Persian literary history that, on the one hand, resulted in the desire to maintain a universal vision regarding the Persianate literary past, exemplified by such writers as Vāleh Dāghestāni in Riāz al-sho' arā', and on the other hand, witnessed the increasingly popular move towards a more local and parochial version of the achievements of poets, as seen in Āzar Bēgdeli's Ātashkada and other writers of biographical dictionaries. The tri-furcation of the literary tradition (Iran, Turan [Transoxiana], India) complicated the way the memory of women poets would be accommodated and tazkera writers were often unencumbered by issues of nationalism and linguistic purity on this subject. However, ultimately the project of canonization of classical Persian women poets was a failure by becoming all inclusive.

scholarly journals Modulation ofβ-Cell Ouabain-SensitiveR86b+Influx (Na+/k+Pump) by D-Glucose, Glibenclamide or Diazoxide

2000 ◽  
Vol 1 (4) ◽  
pp. 265-274 ◽  
Author(s):  
Adrian Elmi ◽  
Lars-ÅKe Idahl ◽  
Janove Sehlin
Keyword(s):  
Atpase Activity ◽  
Direct Effect ◽  
Mechanism Of Action ◽  
The Other ◽  
Pump Function ◽  
Other Hand ◽  
Insulin Secretagogues ◽  
Pre Treatment ◽  
Effect Of Glucose ◽  
Stimulation Of

The activity of theβ-cellNa+/k+pump was studied by using ouabain-sensitive (lmM ouabain)R86b+influx inβ-cell-rich islets of Umeå-ob/obmice as an indicator of the pump function. The present results show that the stimulatory effect of glucose on ouabain-sensitiveR86b+influx reached its approximate maximum at 5mM glucose. Pre-treatment of the islets with 20mM glucose for 60 min strongly reduced the glucose-induced stimulation of theNa+/k+pump. Pre-treatment (60 or 180 min) of islets at 0mM glucose, on the other hand, did not affect the magnitude of the glucose-induced stimulation ofR86b+influx dunng the subsequent 5-min incubation. Glibenclamide stimulated the ouabain-sensitiveR86b+uptake in the same manner as glucose. The stimulatory effect, showed its apparent maximum at 0.5μM. Pre-treatment (60 min) of islets with 1μM glibenclamide did not reduce the subsequent stimulation of the ouabain-sensitiveR86b+influx. The stimulatory effect of glibenclamide and D-glucose were not .additive, suggesting that they may have the same mechanism of action. No direct effect of glibenclamide (0.01-1μM) was observed on theNa+/k+ATPase activity in homogenates of islets. Diazoxide (0.4mM) inhibited theNa+/k+pump. This effect was sustained even after 60 min of pre-treatment of islets with 0.4mM diazoxide. The stimulatory effect of glibenclamide and D-glucose were abolished by diazoxide. It is concluded that nutrient as well as non-nutrient insulin secretagogues activate theNa+/k+pump, probably as part of the membrane repolarisation process.

MODIFICATIONS DES CELLULES GONADOTROPES ET DU CONTENU EN FSH DE LA GLANDE PITUITAIRE DANS LES CONDITIONS DE LA PONTE PROVOQUEE CHEZ LA RATTE

1969 ◽  
Vol 62 (4) ◽  
pp. 607-623 ◽  
Author(s):  
J. Roos
Keyword(s):  
Synergistic Action ◽  
The Other ◽  
Female Rats ◽  
List Type ◽  
Β Cells ◽  
Other Hand

ABSTRACT The action exerted by an early mating on the pituitary β and γ cells and on the pituitary FSH content has been studied in 4-day cyclic female rats which were mated at 5–6 p. m. on dioestrus 2 after being injected with oestradiol (10 μg) at 10–11 p.m. on dioestrus 1. The following results were obtained: Oestradiol alone induces, on one hand, a highly significant decrease with respect to control animals of the percentage of the γ cells, on the other hand, an increase of the granular content of the β cells. Ovulation only occurs in 5 % of these oestrogenized rats. After early mating a further diminution of the percentage of the γ cells was observed concomitantly with a strong degranulation of the β cells; this early coitus triggered ovulation in 52 % of the females. The pituitary FSH bioassay evidenced a stockage of FSH in oestrogenized females with respect to control animals and on the contrary a FSH release under the influence of coitus. It was therefore concluded that early ovulation as well as spontaneous ovulation in the rat require the synergistic action of both FSH and LH gonadotrophic hormones.

scholarly journals 6-Carboxymethyl genistein: a novel selective oestrogen receptor modulator (SERM) with unique, differential effects on the vasculature, bone and uterus

2002 ◽  
Vol 173 (3) ◽  
pp. 415-427 ◽  
Author(s):  
D Somjen ◽  
Y Amir-Zaltsman ◽  
B Gayer ◽  
T Kulik ◽  
E Knoll ◽  
...  
Keyword(s):  
Molecular Modelling ◽  
Oestrogen Receptor ◽  
Specific Activity ◽  
The Other ◽  
Female Rats ◽  
Rat Tissues ◽  
Receptor Modulator ◽  
Other Hand ◽  
Selective Oestrogen Receptor Modulator

The novel genistein (G) derivative, 6-carboxymethyl genistein (CG) was evaluated for its biological properties in comparison with G. Both compounds showed oestrogenic activity in vitro and in vivo. On the other hand G and CG differed in the following parameters: (i) only CG displayed mixed agonist-antagonist activity for oestrogen receptor (ER) alpha in transactivation assays and (ii) only CG was capable of attenuating oestrogen (E(2))-induced proliferation in vascular smooth muscle cells and of inhibiting oestrogen-induced creatine kinase (CK) specific activity in rat tissues. On the other hand only G enhanced the stimulatory effect on CK specific activity in the uterus. In comparison to the selective oestrogen receptor modulator (SERM) raloxifene (RAL), CG showed the same selectivity profile as RAL in blocking the CK response to E(2) in tissues derived from both immature and ovariectomized female rats. Molecular modelling of CG bound to the ligand binding domain (LBD) of ERbeta predicts that the 6-carboxymethyl group of CG almost fits the binding cavity. On the other hand, molecular modelling of CG bound to the LBD of ERalpha suggests that the carboxyl group of CG may perturb the end of Helix 11, eliciting a severe backbone change for Leu 525, and consequently induces a conformational change which could position Helix 12 in an antagonist conformation. This model supports the experimental findings that CG can act as a mixed agonist-antagonist when E(2) is bound to its receptors. Collectively, our findings suggest that CG can be considered a novel SERM with unique effects on the vasculature, bone and uterus.

scholarly journals Immunohistochemical localization of two proteinases in skeletal muscle.

1983 ◽  
Vol 31 (6) ◽  
pp. 827-830 ◽  
Author(s):  
W T Stauber ◽  
V Fritz ◽  
B Dahlmann ◽  
H Reinauer
Keyword(s):  
Skeletal Muscle ◽  
Mast Cells ◽  
Soleus Muscle ◽  
Extensor Digitorum Longus ◽  
Muscle Fibers ◽  
Immunohistochemical Localization ◽  
Extensor Digitorum ◽  
The Other ◽  
Other Hand

Immunohistochemical localizations of cytosolic and myofibrillar proteinases revealed a different myofiber locale for each enzyme in the rat. Although the cytosolic proteinase was most pronounced in mast cells within soleus and extensor digitorum longus (EDL) muscles, certain fibers of the EDL were also positive. The myofibrillar proteinase, on the other hand, appeared to be present in interstitial spaces between muscle fibers in the EDL but conversely present in some fibers of the soleus muscle.

Mechanisms of action of testosterone propionate on LH and FSH release by the pituitary gland in cyclic female rats

1980 ◽  
Vol 95 (2) ◽  
pp. 158-165 ◽  
Author(s):  
J. Roos ◽  
S. Plas-Roser ◽  
Cl. Aron
Keyword(s):  
Pituitary Gland ◽  
Sharp Increase ◽  
Testosterone Propionate ◽  
Sharp Decrease ◽  
Mechanisms Of Action ◽  
The Other ◽  
Female Rats ◽  
Corpora Lutea ◽  
Other Hand ◽  
Lh Release

Abstract. The aim of this work was to determine whether changes in pituitary responsiveness to LRH could account for the effect of testosterone propionate (TP) on the gonadotrophic function of the pituitary in 4-day cyclic female rats. Doses of 250, 500 and 1000 ng LRH were injected ip on pro-oestrus at 15.30 h in rats either pre-treated with 5 mg TP on dioestrus II at 10.00 h or injected with 30 mg/kg pentobarbital (PB) at 13.00 h. LH release induced within 30 min by LRH was higher in PB than in TP-treated rats. Even by using 250 ng LRH full ovulation was observed on the morning of oestrus in PB-treated rats. On the other hand, only partial ovulation occurred whatever the dose of LRH used in TP-treated rats; a great number of luteinized follicles was shown to be constantly associated with post-ovulatory corpora lutea. While LRH caused a significant FSH release (30 min later) in TP-treated rats, no FSH release could be shown in PB-treated rats. The pituitary FSH content appeared to be decreased and the pituitary LH content remained unchanged while a sharp increase in both blood FSH and LH concentrations occurred following injection of 1000 ng LRH in TP-treated rats. Concomitantly a sharp decrease in the number of pituitary gonadotrophs (AB-PAS+) was observed. A significant decrease in the number of the small roundshaped PAS positive cells was also observed. The mechanisms whereby TP influences the function of the pituitary-ovarian axis are discussed in the light of these results.

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