CONCENTRATION OF OESTRADIOL, PROGESTERONE, LUTEINIZING HORMONE AND FOLLICLE-STIMULATING HORMONE IN THE JUGULAR VENOUS PLASMA OF EWES DURING THE OESTROUS CYCLE

1977 ◽  
Vol 73 (2) ◽  
pp. 247-255 ◽  
Author(s):  
H. C. PANT ◽  
C. R. N. HOPKINSON ◽  
R. J. FITZPATRICK

SUMMARY Changes in the concentrations of ovarian steroids and pituitary gonadotrophins were measured by radioimmunoassay in the jugular plasma of six Clun Forest ewes throughout the oestrous cycle. The concentration of oestradiol began to rise 12–14 h before the onset of oestrus from values of 11·2 ± 0·36 (s.e.m.) pg/ml during the luteal phase to 21·1 ± 2·01 pg/ml at −8 to 0 h (oestrus). There was no distinct increase during the luteal phase. Circulating progesterone varied in a cyclic manner with the highest values at the mid-luteal phase (3·70 ± 0·28 ng/ml; n = 28). In five out of six ewes the concentration was still quite high (1·86 ± 0·43 ng/ml) at 35 h before the onset of oestrus. The concentration declined rapidly thereafter, reaching minimum values about 12 h before oestrus coincident with the increase in oestradiol concentration. Plasma LH increased from very low values of 2·59 ± 0·09 ng/ml during the luteal phase to 75·3 ± 7·4 ng/ml about 9 h after the onset of oestrus. Two peaks of plasma FSH concentration were detected after the onset of oestrus. The first peak (171·0± 35·5 ng/ml) coincided with the LH peak and the second (133·0 ± 10·7 ng/ml) occurred about 24 h later at a time when LH values were low. The mean FSH concentration at other times during the cycle was 61·9 ± 2·8 ng/ml.

1981 ◽  
Vol 34 (1) ◽  
pp. 67 ◽  
Author(s):  
KP McNatty ◽  
M Gibb ◽  
C Dobson ◽  
DC Thurley ◽  
JK Findlay

The concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, progesterone, androstenedione and oestradiol were determined in the antral fluid of ovarian follicles > 1 mm in diameter as well as in ovarian venous or peripheral venous plasma, or both, from at least four different animals on each day throughout the oestrous cycle of the sheep. The individual steroid hormones in antral fluid were examined in relation to the steroid-secretion rates in ovarian venous plasma, follicle size and the hormone levels in jugular venous plasma.


Reproduction ◽  
2000 ◽  
pp. 49-57 ◽  
Author(s):  
SD Johnston ◽  
MR McGowan ◽  
P O'Callaghan ◽  
R Cox ◽  
V Nicolson

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.


1979 ◽  
Vol 91 (3) ◽  
pp. 591-600 ◽  
Author(s):  
Toshihiro Aono ◽  
Akira Miyake ◽  
Takenori Shioji Motoi Yasuda ◽  
Koji Koike ◽  
Keiichi Kurachi

ABSTRACT Five mg of bromocriptine was administered for 3 weeks to 8 hyperprolactinaemic women with galactorrhoea-amernorrhoea, in whom the response of serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) to 100 μg of iv LH-releasing hormone (LH-RH) had been evaluated. Twenty mg of conjugated oestrogen (Premarin®) was injected iv any day between the 10th and 12th day from the initiation of the treatment, and serum LH levels were serially determined for 120 h. Hyperresponse of LH with normal FSH response to LH-RH was observed in most patients. Bromocriptine treatment for 10 to 12 days significantly suppressed mean (± se) serum prolactin (PRL) levels from 65.1 ± 23.0 to 10.4 ± 2.0 ng/ml, while LH (12.6 ± 2.1 to 24.8 ± 5.9 mIU/ml) and oestradiol (40.1 ± 7.6 to 111.4 ± 20.8 pg/ml) levels increased significantly. Patients on bromocriptine treatment showed LH release with a peak at 48 h after the injection of Premarin. The mean per cent increases in LH were significantly higher than those in untreated patients with galactorrhoea-amenorrhoea between 32 and 96 h after the injection. The present results seem to suggest that the restoration of LH-releasing response to oestrogen following suppression of PRL by bromocriptine may play an important role in induction of ovulation in hyperprolactinaemic patients with galactorrhoea-amenorrhoea.


1982 ◽  
Vol 243 (5) ◽  
pp. E387-E397 ◽  
Author(s):  
A. L. Goodman ◽  
G. D. Hodgen

To learn how progesterone (P) inhibits follicle growth during the luteal phase, we determined whether P will inhibit follicle growth when follicle-stimulating hormone (FSH) is secreted in large amounts, namely, after luteectomy (CLX) in monkeys with only one ovary. Second, a functional role for 17 alpha-hydroxyprogesterone (17OHP) was examined as a common mediator of the inhibition of folliculogenesis by the dominant follicle and corpus luteum. To accomplish the first goal, nine chronically hemiovarectomized monkeys were lutectomized chronically hemiovariectomized monkeys were luteectomized at midluteal phase. In five monkeys that received no steroid, the next preovulatory luteinizing hormone (LH) surge occurred 14.0 +/- 0.8 days (mean +/- SE) after CLX. In contrast, the next LH surge was delayed in four monkeys implanted for 10 days with Silastic capsules containing P and occurred 25.0 +/- 2.7 days after CLX, i.e., 14.8 +/- 2.7 days after the capsule removal. In both groups, FSH levels increased markedly after CLX to a comparable degree and duration; yet, only a single follicle ovulated in each monkey. To examine a potential inhibitory role for 17OHP, monkeys with two ovaries were luteectomized and received 1) no steroid, 2) 17OHP via Silastic capsules, or 3) P for 10 days after CLX. Progesterone replacement after CLX appeared to maintain 17OHP levels, which showed a transient decrease after CLX alone. As above, P delayed the next LH surge (25.4 +/- 1.3 vs. 15.0 +/- 0.6 days) despite comparable increases in serum FSH after CLX alone. Replacement at two levels of 17OHP did not delay the onset of menses (2-3 days post-CLX) or significantly delay the next LH surge 18.3 +/!- 1.9 or 20.8 +/- 3.4 vs. 15.0 +/- 0.6 days (P greater than 0.2) in monkeys CLX only. Whatever may be the mode of action of P, it appears that it is not mediated by peripheral conversion to 17OHP. These findings demonstrate that P at luteal phase levels can inhibit follicle growth culminating in ovulation even in the face of sustained, elevated levels of endogenous FSH. Because single ovulations occurred despite unambiguous and prolonged increments in serum FSH after CLX, the precise regulation of the ovulatory quota in this primate appears to be accomplished by means other than FSH alone.


1971 ◽  
Vol 68 (3) ◽  
pp. 502-512 ◽  
Author(s):  
Elof D. B. Johansson ◽  
Leif Wide ◽  
Carl Gemzell

ABSTRACT The plasma levels of luteinizing hormone (LH) and progesterone and the urinary excretion of LH and oestrogens were measured during the normal menstrual cycle of 22 young and healthy women. A total of 42 cycles were investigated. The urinary excretion of total oestrogens increased during several days before the rise of LH in the urine. The day of maximum excretion of LH and total oestrogens coincided during the midcycle period. The mid-cyclic rise in LH was found to occur on the same day in the plasma and urine and the days of maximum values coincided in 11 out of 16 cycles. In 5 cycles the maximum level was reached one day later in the urine. The plasma levels of progesterone started to increase during the LH and oestrogen peaks. The days for maximum levels of progesterone coincided with the second peak of urinary oestrogens. The levels of progesterone in the plasma reached values above 10 ng per ml in all normal cycles. The plasma levels of progesterone were below 1 ng per ml plasma when menstrual bleeding started. The length of the luteal phase was 14.4 ± 1.1 (s) days. The sum of daily urinary excretion of total oestrogens and the sum of the daily plasma progesterone levels varied within 15 per cent of the mean in five out of six women studied during more than two cycles. The variation in values for the sums of daily oestrogen excretion and plasma progesterone levels was considerably larger between menstrual cycles of different women than between menstrual cycles of the same woman.


1976 ◽  
Vol 68 (3) ◽  
pp. 409-417 ◽  
Author(s):  
J. P. FOSTER ◽  
S. L. JEFFCOATE ◽  
D. B. CRIGHTON ◽  
D. T. HOLLAND

SUMMARY Luteinizing hormone and LH-RH-like immunoreactivity were measured in the jugular venous plasma of Clun Forest ewes at various stages of the oestrous cycle. Blood samples were collected through jugular venous cannulae every 2 h for at least 20 days from three ewes during the breeding season. The ewes were checked twice daily for oestrus using a vasectomized ram. Plasma LH peaks of apparent height 112–192 ng NIH-LH-S17 equivalents/ml were detected at oestrus with basal levels of 2–15 ng/ml during most of the remainder of the 17-day oestrous cycle. Peaks of LH-RH-like immunoreactivity occurred at various times of the cycle. The apparent maximal level of these peaks was 220 pg/ml compared with basal levels of < 10 pg/ml. Further ewes (two for each group) were sampled at 4 min intervals for 12 h, (1) from onset of oestrus, (2) 36–48 h after onset of oestrus or (3) on day 10 of the oestrous cycle. In the ewes sampled at oestrus, peaks of LH-RH-like immunoreactivity were detected before, during and after the preovulatory LH peak. Those detected after the LH peak were unassociated with any further increases in the plasma LH level. In the ewes sampled 36–48 h after onset of oestrus and on day 10 of the cycle, several peaks of LH-RH-like immunoreactivity unassociated with any increases in the LH level were detected. These peaks, and those detected at oestrus, had durations of only one or two samples, and in some cases reached levels of several ng/ml compared with basal levels of < 10 pg/ml. The significance of these results is discussed.


1976 ◽  
Vol 83 (4) ◽  
pp. 684-691 ◽  
Author(s):  
Sven Johan Nillius ◽  
Leif Wide

ABSTRACT Modulating effects of oestradiol-17β and progesterone on the pituitary responsiveness to luteinizing hormone-releasing hormone (LRH) were investigated in 12 women with functional amenorrhoea. The pituitary reserve capacity for gonadotrophin section was investigated with repeated intravenous LRH tests before and after administration of oestradiol-1β followed by either progesterone or saline. Intramuscular injection of 1 mg of oestradiol-17β benzoate resulted in a suppression of both the basal gonadotrophin levels in serum and the gonadotrophin responses to LRH 24 h later. Progesterone, 25 mg im, was then administered in eleven experiments. Six h later, when the mean serum progesterone level had increased to levels similar to those seen in the early post-ovulatory phase of the menstrual cycle, there was a marked augmentation of the pituitary capacity to release both luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in response to LRH. This was not found in eight experiments where saline was given instead of progesterone after oestrogen pretreatment. These findings suggest that the greatly increased pituitary sensitivity to LRH at midcycle may be caused not only by the oestradiol increase in blood during the late follicular phase but also in part by the small pre-ovulatory rise of progesterone during the mid-cyclic LH peak. Furthermore, they add further support to the hypothesis that progesterone as well as oestradiol is involved in the induction of the LH peak at midcycle. Progesterone may be of importance to secure the release of enough LH for ovulation and normal corpus luteum formation to occur.


1975 ◽  
Vol 80 (4) ◽  
pp. 676-685 ◽  
Author(s):  
J. A. Elias ◽  
J. R. Newton ◽  
W. P. Collins

ABSTRACT The concentrations of prostaglandin F2α, progesterone, oestradiol, LH and cortisol have been determined in serial samples of peripheral venous plasma, before, during and after, the intravenous administration of prostaglandin F2α (50 μg/min, for 5 h) to 8 women in the luteal phase of the ovarian cycle. The results show that the mean concentrations of prostaglandin F2α and cortisol increased during the infusion by factors of 8.8 and 2.6 respectively. The highest levels of cortisol occurred after 3 h, and were significantly different (P < 0.0005, Student's t-test) from those obtained before the infusion. There were progressive decreases in the concentrations of LH and progesterone. After 3 h the values for LH were significantly lower (P < 0.0025) than those before the administration of prostaglandin F2α, and the lowest mean value was 26 % of the control. The values for progesterone were significantly lower (P < 0.025) after 5 h, and the mean value at this time was 38 % of the control. The pattern of the mean concentration for oestradiol was similar to that for progesterone. The levels of all 5 compounds had returned to normal within 1 h after completion of the infusion. The findings are discussed.


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