ENDOCRINE CONTROL OF ENDOMETRIAL SENSITIVITY DURING THE INDUCTION OF THE DECIDUAL CELL REACTION IN THE MOUSE

1966 ◽  
Vol 36 (3) ◽  
pp. 239-248 ◽  
Author(s):  
C. A. FINN
Keyword(s):  
Time Interval ◽  
Decidual Cell ◽  
Cell Reaction ◽  
Endocrine Control ◽  
Optimum Time ◽  
Ovariectomized Mice

SUMMARY The decidual cell reaction (DCR) of ovariectomized mice treated with hormones and stimulated by the intrauterine injection of oil was investigated to obtain information about the control of uterine sensitivity during implantation. Three factors were studied; oestrogen given at the time of oestrus, progesterone and oestrogen given at the time of the nidatory surge. For the induction of the DCR by oil both 'oestrous' oestrogen and 'nidatory surge' oestrogen were essential, whereas neither were necessary for the traumatic DCR. The quantity of nidatory surge oestrogen was very critical; 0·01 μg. were effective, 0·0625 μg. inhibitory. There was no quantitative interaction between nidatory surge oestrogen and progesterone, indicating that in this situation the two hormones are acting independently. The optimum time interval between initiating the oestrogen surge and injecting the oil was between 4 and 8 hr. No response was obtained when the oestrogen surge was produced and the stimulus applied on the second day of treatment with progesterone; maximal responses were obtained on the fourth and fifth day and a reduced response on the seventh day. After an oestrogen surge on the fourth day, it was not possible to elicit an oil DCR to a further dose of oestrogen on the fifth day, indicating that the period of sensitivity induced by the surge on the fourth day is followed by a period of refractoriness.

Some biological activities of cronolone and medroxyprogesterone acetate in the uterus of the sheep, mouse and rabbit

1989 ◽  
Vol 1 (2) ◽  
pp. 157 ◽  
Author(s):  
X Zhang ◽  
BG Miller
Keyword(s):  
Biological Activity ◽  
Medroxyprogesterone Acetate ◽  
Biological Activities ◽  
Decidual Cell ◽  
Cell Reaction ◽  
Limited Growth ◽  
Mouse Uterus ◽  
Breeding Activity ◽  
Ovariectomized Mice

Cronolone (9 alpha-fluoro-11 beta-hydroxy-17 alpha-acetoxypregn-4-ene-3,20-dione) is widely employed to regulate breeding activity in the ewe, but its biological activity in the uterus of this and most other species has not been studied. In this study several in vivo uterus-related activities of cronolone have been examined in the sheep, mouse and rabbit. In some experiments the corresponding activities of medroxyprogesterone acetate (6 alpha-methyl-17 alpha-acetoxypregn-4-ene-3,20-dione, MAP) were also examined. Cronolone maintained pregnancy in ovariectomized ewes but not in ovariectomized mice and rabbits; it terminated pregnancy in some mice and in all rabbits that were receiving daily progesterone treatment. Cronolone could not sensitize the mouse uterus for the induction of the decidual-cell reaction or block the induction of such sensitivity by progesterone, but did support limited growth of the oil-stimulated horn after sensitization with progesterone. Cronolone induced uteroglobin secretion by rabbit endometrium. It was concluded that, whereas MAP is a potent progestogen in the sheep, mouse and rabbit, cronolone is a progestogen in the sheep and rabbit only. In the mouse and especially the rabbit, cronolone has other, non-progestational activities, which block pregnancy.

EFFECT OF PROGESTERONE ON SURVIVAL OF BLASTOCYSTS IN UTERI OF OVARIECTOMIZED MICE

1971 ◽  
Vol 51 (2) ◽  
pp. 375-NP ◽  
Author(s):  
H. M. WEITLAUF
Keyword(s):  
Time Interval ◽  
Ovariectomized Mice ◽  
Vaginal Plug

SUMMARY Mice were ovariectomized on day 4 of pregnancy and injected daily with either progesterone or oil vehicle (day 1 = the day of vaginal plug). Blastocysts were recovered on day 10, 20 or 30, counted and transferred to ovariectomized recipients. Implantation was induced and pregnancy maintained by daily injections of oestradiol and progesterone. Viability of the blastocysts was assessed by determining the percentage that developed into normal foetuses. A similar number of eggs was recovered from both groups at each time-interval; thus progesterone did not influence the retention of blastocysts by ovariectomized mice. In contrast, progesterone did influence the viability of the embryos. The percentage of blastocysts developing normally from the oil-treated animals was: 39% on day 10, 19% on day 20 and less than 1% on day 30. Corresponding percentages for the progesterone-treated animals were: 40% on day 10, 35% on day 20 and 35% on day 30.

scholarly journals Effect of relaxin on the decidual cell reaction in the Mongolian gerbil (Meriones unguiculatus)

2009 ◽  
Vol 8 (4) ◽  
pp. 163-167
Author(s):  
Mayumi Yoshida ◽  
M. S. Hossain ◽  
K. M. A. Tareq ◽  
Ryuichiro Obata ◽  
Hirotada Tsujii
Keyword(s):  
Mongolian Gerbil ◽  
Meriones Unguiculatus ◽  
Decidual Cell ◽  
Cell Reaction

scholarly journals Evaluation of Optimal Occasional Tilt on Photovoltaic Power Plant Energy Efficiency and Land Use Requirements, Iran

2021 ◽  
Vol 13 (18) ◽  
pp. 10213
Author(s):  
Amirhossein Fathi ◽  
Masoomeh Bararzadeh Ledari ◽  
Yadollah Saboohi
Keyword(s):  
Power Plant ◽  
Solar Radiation ◽  
Solar Energy ◽  
Orientation Angle ◽  
Optimum Operating ◽  
Time Interval ◽  
Time Intervals ◽  
Optimum Time ◽  
Equal Time ◽  
Geographical Regions

The paper studies the optimum panel horizontal orientation angle toward the Sun and the optimum time interval of the panel’s movement. The optimum time intervals or panel movement can change the rate of input energy to the panel surface in Iran. For this purpose, a neural network has been trained to estimate the intensity of solar radiation in Iran. After model validation, the intensity of solar radiation has been estimated by selecting adequate geographical regions. Based on the intensity of sunlight, Iran has been divided into ten regions. In these regions, 40 cities have been randomly selected to study the effect of the panel’s angle variations within appropriate time intervals, as well as equal time intervals. The results show that the choice of the mounting system with the possibility of five angles’ implementation can increase the amount of solar energy between 3.9% and 7.4%. Compared to this number of angles at the equal time intervals, the amount of incoming solar energy has increased by 3% to 7%. In the first and second cases, the area of the power plant increases by about 12% to 24% compared to the yearly optimum tilt angle. Moreover, the amount of radiation incoming to the panel with the optimum operating angle is in alignment with the results of PVsyst software.

Sign in / Sign up

Export Citation Format

Share Document