Cerebral Thrombosis And Microcirculation Of The Rat During The Oestrous Cycle And After Ovariectomy

2002 ◽  
Vol 29 (1-2) ◽  
pp. 73-78 ◽  
Author(s):  
H Ono ◽  
Y Sasaki ◽  
E Bamba ◽  
J Seki ◽  
JC Giddings ◽  
...  
Keyword(s):  
Oestrous Cycle ◽  
Cerebral Thrombosis

Adhesive Platelet Count and Blood Coagulability in Myocardial Infarction and Cerebral Thrombosis

1970 ◽  
Vol 24 (03/04) ◽  
pp. 450-460 ◽  
Author(s):  
H Yamazaki ◽  
T Odakura ◽  
K Takeuchi ◽  
T Sano
Keyword(s):  
Myocardial Infarction ◽  
Platelet Count ◽  
Malignant Tumors ◽  
Total Cholesterol Level ◽  
Statistical Significance ◽  
Acute Stage ◽  
Cerebral Thrombosis ◽  
Prothrombin Activity ◽  
Recovery Stage ◽  
Blood Coagulability

SummaryIn 382 patients, aged 21 to 76 years, including 39 healthy volunteers, a platelet count by Olef’s method, an adhesive platelet count by Moolten-Vroman’s method, prothrombin activity due to one-stage prothrombin time and calcium clotting time were measured. In 39 cases of myocardial infarction and 40 cases of cerebral thrombosis, both in acute stage, a marked decrease in the adhesive platelet count and adhesive index and an increase of prothrombin activity were observed with statistical significance compared to the healthy group (P < 0.01). In the recovery stage of myocardial infarction, cerebral thrombosis and other diseases, except for malignant tumors, acute infectious diseases, diabetes mellitus and blood or liver diseases, the above observations were absent or reduced. In the case of thrombosis, a negative correlation was seen between the adhesive platelet count and prothrombin activity (r — —0.238, P < 0.01). There is no correlation between the changes in platelet adhesiveness or blood coagulability and total cholesterol level in serum.

NEW DATA CONCERNING THE ROLE PLAYED BY PROGESTERONE IN THE CONTROL OF FOLLICULAR GROWTH IN THE RAT

1974 ◽  
Vol 75 (3) ◽  
pp. 569-578 ◽  
Author(s):  
G. Buffler ◽  
S. Roser
Keyword(s):  
Wistar Rats ◽  
Venous Blood ◽  
Oestrous Cycle ◽  
Female Rats ◽  
Cycle Duration ◽  
Follicular Growth ◽  
The Third ◽  
Female Wistar Rats

ABSTRACT The mechanisms involved in the prolongation of the oestrous cycle following LH administration were studied in 4-day cyclic female Wistar rats. In females injected with LH on the morning of dioestrus I there was an increase in ovarian venous blood progesterone as compared with non-injected animals. In both LH-treated females, and those injected with progesterone on the morning of dioestrus I, a slowing up in follicular growth was observed from the afternoon of dioestrus I. The size of follicles greater than 400 urn present in LH or progesterone injected animals on the third day of cycle was similar to the size reached by the same range of follicles in non-injected animals on the second day of the cycle. Hence, the increase in endogenous ovarian progesterone elicited by LH was considered as the cause of the slowing up of follicular growth and therefore of the lengthening of the oestrous cycle duration in female rats injected with LH at the beginning of 4-day cycle.

FSH AND LH LEVELS IN THE INTACT AND UNILATERALLY OVARIECTOMIZED CYCLING RAT

1972 ◽  
Vol 69 (2) ◽  
pp. 267-280 ◽  
Author(s):  
Richard D. Peppler
Keyword(s):  
Plasma Concentrations ◽  
Follicular Development ◽  
Slight Modification ◽  
Oestrous Cycle ◽  
Successive Cycle ◽  
Unilateral Ovariectomy ◽  
Subsequent Cycle ◽  
Intact Rats

ABSTRACT Intact 5-day cycling rats were killed between 8–10 a. m. on each day of the oestrous cycle; experimental rats were unilaterally ovariectomized (ULO) at 9 a. m. on day 1 (oestrus) and killed between 8 and 10 a. m. on days 2, 3, 4 or 1 of the subsequent cycle. Pituitary and plasma concentrations of FSH and LH were measured in both groups of rats. Pituitary FSH concentration was measured by the Steelman-Pohley method with slight modification; plasma FSH by the Igarashi-McCann assay and pituitary and plasma LH concentration by the OAAD method. In intact rats, pituitary FSH values remained constant for the first three days of the cycle, increased on day 4 and reverted to early cycle values by day 5. Plasma FSH increased between days 2 and 3 and days 5 and 1. Pituitary LH concentration remained the same for days 1 and 2; increased two-fold on days 3 and 4, and increased further by day 5. Plasma LH increased between days 2 and 3; other differences between successive cycle days were not apparent. Following ULO on day 1, pituitary FSH increased steadily, but not significantly, for the remaining cycle. Plasma FSH did not change from day 2 through day 1 of the subsequent cycle. Pituitary LH remained low on day 2, increased sharply by day 3 and decreased (50 %) by day 4. Plasma LH also increased between days 2 and 3. Other differences between successive days following unilateral ovariectomy on day 1 were not apparent. Correlation of gonadotrophin activity with follicular development suggests that the mechanism of compensatory ovulation in the rat may be one of an increase in time of exposure to a constant gonadotrophic level for the duration of the oestrous cycle rather than to increased levels of the gonadotrophin.

EFFECT OF FEEDING ETHINYLOESTRADIOL FOR VARIOUS PERIODS BEFORE MATING ON REPRODUCTION IN THE HAMSTER

1972 ◽  
Vol 70 (3) ◽  
pp. 582-590
Author(s):  
B. K. Davis ◽  
I. Noske ◽  
M. C. Chang
Keyword(s):  
Single Dose ◽  
Pregnancy Rate ◽  
Fertility Control ◽  
Normal Pregnancy ◽  
Oestrous Cycle ◽  
The Other ◽  
Feeding Schedule ◽  
Crown Rump Length ◽  
Essentially Normal ◽  
Effect Of Feeding

ABSTRACT Ethinyloestradiol (EO) fed for various periods before mating to female hamsters affected the timing of mating and pregnancy rate. Slight effects on ovulation, foetal-crown rump length and resorption may have occurred, but effects on implantation were not apparent among pregnant hamsters. The response observed depended upon the feeding schedule adopted: hamsters fed 2.5 mg EO in a single dose, on day 3 before mating, mated normally but had a significantly lower pregnancy rate; on the other hand, animals fed 2.5 mg EO (0.21 mg/day) over three oestrous cycles, days 14–3 before mating, showed variations in the time of mating but had an essentially normal pregnancy rate; and, a group of hamsters who received the same total amount of EO (0.63 mg/day) over one oestrous cycle, days 6–3 premating, showed untowards effects by the steroid on both the timing of mating and pregnancy rate. The implications of these results are considered in relation to fertility control.

Ovarian secretion of estradiol during the oestrous cycle in the ewe

Reproduction ◽  
1971 ◽  
Vol 24 (1) ◽  
pp. 133-134 ◽  
Author(s):  
R. Cox ◽  
P. Mattner ◽  
D. Shutt ◽  
G. Thorburn
Keyword(s):  
Oestrous Cycle

Studies of the oestrous cycle, oestrus and pregnancy in the koala (Phascolarctos cinereus)

Reproduction ◽  
2000 ◽  
pp. 49-57 ◽  
Author(s):  
SD Johnston ◽  
MR McGowan ◽  
P O'Callaghan ◽  
R Cox ◽  
V Nicolson
Keyword(s):  
Luteal Phase ◽  
Post Partum ◽  
Plasma Concentrations ◽  
External Genitalia ◽  
Oestrous Cycle ◽  
Phascolarctos Cinereus ◽  
Pregnant Females ◽  
Peripheral Plasma ◽  
The Mean ◽  
High Concentrations

As an integral part of the development of an artificial insemination programme in the captive koala, female reproductive physiology and behaviour were studied. The oestrous cycle in non-mated and mated koalas was characterized by means of behavioural oestrus, morphology of external genitalia and changes in the peripheral plasma concentrations of oestradiol and progestogen. The mean (+/- SEM) duration of the non-mated oestrous cycle and duration of oestrus in 12 koalas was 32.9 +/- 1.1 (n = 22) and 10.3 +/- 0.9 (n = 24) days, respectively. Although the commencement of oestrous behaviour was associated with increasing or high concentrations of oestradiol, there were no consistent changes in the morphology or appearance of the clitoris, pericloacal region, pouch or mammary teats that could be used to characterize the non-mated cycle. As progestogen concentrations remained at basal values throughout the interoestrous period, non-mated cycles were considered non-luteal and presumed anovulatory. After mating of the 12 koalas, six females gave birth with a mean (+/- SEM) gestation of 34.8 +/- 0.3 days, whereas the remaining six non-parturient females returned to oestrus 49.5 +/- 1. 0 days later. After mating, oestrous behaviour ceased and the progestogen profile showed a significant increase in both pregnant and non-parturient females, indicating that a luteal phase had been induced by the physical act of mating. Progestogen concentrations throughout the luteal phase of the pregnant females were significantly higher than those of non-parturient females. Parturition was associated with a decreasing concentration of progestogen, which was increased above that of basal concentrations until 7 days post partum.

Effect of cortisol on neurophysin I/oxytocin and peptidyl glycine-α-amidating mono-oxygenase mRNA expression in bovine luteal and granulosa cells

2013 ◽  
Vol 16 (2) ◽  
pp. 231-239
Author(s):  
A. Ziolkowska ◽  
J. Mlynarczuk ◽  
J. Kotwica
Keyword(s):  
Mrna Expression ◽  
Granulosa Cells ◽  
Molecular Mechanisms ◽  
Hormone Secretion ◽  
Oestrous Cycle ◽  
Luteal Cells ◽  
Ru 486 ◽  
Ovarian Cells ◽  
Key Genes ◽  
Ovary Function

Abstract Cortisol stimulates the synthesis and secretion of oxytocin (OT) from bovine granulosa and luteal cells, but the molecular mechanisms of cortisol action remain unknown. In this study, granulosa cells or luteal cells from days 1-5 and 11-15 of the oestrous cycle were incubated for 4 or 8 h with cortisol (1x10-5, 1x10-7 M). After testing cell viability and hormone secretion (OT, progesterone, estradiol), we studied the effect of cortisol on mRNA expression for precursor of OT (NP-I/OT) and peptidyl glycine-α-amidating mono-oxygenase (PGA). The influence of RU 486 (1x10-5 M), a progesterone receptor blocker and inhibitor of the glucocorticosteroid receptor (GR), on the expression for both genes was tested. Cortisol increased the mRNA expression for NP-I/OT and PGA in granulosa cells and stimulated the expression for NP-I/OT mRNA in luteal cells obtained from days 1-5 and days 11-15 of the oestrous cycle. Expression for PGA mRNA was increased only in luteal cells from days 11-15 of the oestrous cycle. In addition, RU 486 blocked the cortisol-stimulated mRNA expression for NP-I/OT and PGA in both types of cells. These data suggest that cortisol affects OT synthesis and secretion in bovine ovarian cells, by acting on the expression of key genes, that may impair ovary function.

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