The human corpus luteum secretes 5α-pregnane-3,20-dione

1986 ◽  
Vol 111 (1) ◽  
pp. 116-121 ◽  
Author(s):  
Torbjörn Bäckström ◽  
Agneta Andersson ◽  
David T. Baird ◽  
Gunnar Selstam

Abstract. A radioimmunoassay for 5α-pregnane-3,20-dione (5α-DHP) in plasma is described. The concentration of 5α-DHP in peripheral plasma during the follicular phase of the menstrual cycle was of the same order of magnitude as that of progesterone (P). During the luteal phase, the plasma 5α-DHP was 8-fold higher than in the follicular phase and about 1/3 of the P concentration. The concentration of 5α-DHP in ovarian venous plasma draining an ovary containing the corpus luteum was 22-fold higher than the concentration in plasma from the contralateral ovarian vein. These results show that the corpus luteum secretes significant amounts of 5α-DHP.

1974 ◽  
Vol 63 (1) ◽  
pp. 201-212 ◽  
Author(s):  
D. T. BAIRD ◽  
P. E. BURGER ◽  
G. D. HEAVON-JONES ◽  
R. J. SCARAMUZZI

SUMMARY The site of secretion of androstenedione in women was investigated by measuring the concentration of androstenedione in peripheral and ovarian venous plasma by radioimmunoassay at different stages of the menstrual cycle. The concentration in peripheral plasma rose from 1·45 ± 0·11 (s.e.m.) ng/ml on day 1 to a peak on the 7 days around mid-cycle (2·29 ± 0·08) before declining gradually during the luteal phase. The concentration of androstenedione in plasma draining ovaries containing the pre-ovulatory follicle or a corpus luteum (33·2 ± 9·0) was significantly higher than in plasma draining the contralateral ovary (10·1 ± 1·6, P < 0·001). In women in whom ovulation was induced with gonadotrophins the concentration of androstenedione in peripheral plasma rose from 1·42 ± 0·21 before treatment to reach maximum levels (2·5–4·5 ng/ml) in the luteal phase. There was a significant (P < 0·001) correlation between the concentration of androstenedione and oestradiol-17β in peripheral (r = 0·50) and ovarian (r = 0·79) venous plasma. These findings indicate that all three cellular compartments in the ovary secrete significant amounts of androstenedione in women during their reproductive life.


1976 ◽  
Vol 71 (1) ◽  
pp. 77-85 ◽  
Author(s):  
K. P. McNATTY ◽  
D. T. BAIRD ◽  
A. BOLTON ◽  
P. CHAMBERS ◽  
C. S. CORKER ◽  
...  

SUMMARY The concentrations of androstenedione, testosterone, oestrone and oestradiol-17β were measured in peripheral and ovarian venous blood and follicular fluid of women at various stages of the menstrual cycle. The concentration of oestradiol was similar in small follicles (diameter < 8 mm) at all stages of the menstrual cycle and in large follicles (diameter ⩾ 8 mm) except during the mid- and late follicular phase when the concentration reached a peak (∼ 1500 ng/ml). The concentration of androstenedione was lowest in large preovulatory follicles at mid-cycle at a time when the secretion into the ovarian vein was markedly increased. The concentration of testosterone in large follicles (⩾ 8 mm) was unchanged during the follicular phase whereas in small follicles there was a peak at mid-cycle. The rise in the concentration of testosterone and androstenedione at mid-cycle in peripheral plasma may be due to increased secretion by the preovulatory follicle into the ovarian vein. It is suggested that the relatively low concentration of androstenedione in follicular fluid of the preovulatory follicle arises from increased aromatization by granulosa cells in the course of oestrogen synthesis.


1977 ◽  
Vol 73 (1) ◽  
pp. 115-122 ◽  
Author(s):  
I. A. SWANSTON ◽  
K. P. McNATTY ◽  
D. T. BAIRD

SUMMARY The concentration of prostaglandin F2α (PGF2α), progesterone, pregnenolone, oestradiol-17β, oestrone, androstenedione and testosterone was measured in corpora lutea obtained from 40 women at various stages of the menstrual cycle. The concentration of PGF2α was significantly higher in corpora lutea immediately after ovulation (26·7 ± 3·9 (s.e.m.) ng/g, P < 0·005) and in corpora albicantia (16·3 ± 3·3 ng/g, P < 0·005) than at any other time during the luteal phase. There was no correlation between the concentration of PGF2α and that of any steroid. The progesterone concentration was highest in corpora lutea just after ovulation (24·9 ± 6·7 μg/g) and in early luteal groups (25·7 ± 6·8 μg/g) but declined significantly (P < 0·05) to its lowest level in corpora albicantia (1·82 ± 0·66 μg/g). The concentration of oestradiol-17β in the corpus luteum and luteal weight were significantly greater during the mid-luteal phase than at any other stage (concentration 282 ± 43 ng/g, P < 0·05; weight 1·86 ± 0·18 g, P < 0·005). The results indicate that regression of the human corpus luteum is not caused by a rise in the ovarian concentration of PGF2α in the late luteal phase of the cycle.


1963 ◽  
Vol 26 (1) ◽  
pp. 155-169 ◽  
Author(s):  
R. V. SHORT ◽  
M. F. McDONALD ◽  
L. E. A. ROWSON

SUMMARY Ewes on the 9th and 15th days of the oestrous cycle were injected intravenously with follicle stimulating hormone, luteinizing hormone and prolactin of sheep pituitary origin, human chorionic gonadotrophin, pregnant mares' serum and an endometrial extract. The ovarian vein was cannulated, and progesterone measured chemically in the venous effluent. None of the above substances was capable of producing a pronounced or sustained alteration in the rate of progesterone secretion in the hour following injection. It was concluded that the ovine corpus luteum, if it responds at all to gonadotrophic stimulation, must do so in a manner very different from the testis, the response of which to luteinizing hormone is both immediate and sustained. The mean secretion rate of progesterone was approx. 150 μg./hr., thus being of the same order of magnitude as a previous indirect estimate of 113 μg./hr. There was no difference in the secretion rate between the 9th and 15th days of the cycle, apart from one animal at the 15th day in which the corpus luteum had ceased to secrete progesterone altogether. The turnover time of progesterone in the corpus luteum was 10 min., suggesting that the hormone is released from the gland as soon as it is formed. Pooled samples of ovarian vein plasma collected during the mid- and late luteal stages of the cycle contained, apart from progesterone, pregnenolone, 20α-hydroxypregn-4-en-3-one, oestrone and oestradiol-17β. In three samples of ovarian vein plasma collected from ewes in oestrus it was impossible to detect progesterone or 20α-hydroxypregn-4-en-3-one, even after chorionic gonadotrophin therapy. Oestradiol-17β and oestrone were present in concentrations similar to those found during the luteal phase of the cycle. Since the rate of ovarian vein blood flow is lower at oestrus than during the luteal phase, it follows that the oestrogen secretion rates are also lower at oestrus. The 24 hr. secretion rate of oestradiol-17β in two oestrous ewes was 3·3–7·4 μg. This is in close agreement with the median effective dose of 7 μg. of oestradiol-17β needed to induce oestrus in the spayed, progesterone-primed ewe.


1994 ◽  
Vol 42 (12) ◽  
pp. 1565-1573 ◽  
Author(s):  
T Suzuki ◽  
H Sasano ◽  
H Sasaki ◽  
T Fukaya ◽  
H Nagura

To understand changes associated with the menstrual cycle in the human ovary, it is very important to examine chronological changes in P450 aromatase (P450arom) enzymatic activity in the normal cycling ovary. Therefore, we initially examined the correlation between intensity of P450arom immunoreactivity and its biochemical enzymatic activity in five estrogen-producing human cancer cell lines (HHUA, Ishikawa, HEC-59, OMC-2, and MCF-7). P450arom immunointensity per cell was evaluated by the CAS 200 computed image analysis system, and its catalytic activity per 10(6) culture cells was analyzed by the tritiated water method. A significant correlation (r = 0.959) was demonstrated between P450arom immunoreactivity and enzymatic activity under optimal conditions of tissue fixation and immunohistochemical procedures. We then investigated P450arom immunointensity in 31 specimens of normal cycling human ovaries to examine chronological changes in P450arom activity per cell throughout the menstrual cycle. In the follicular phase, P450arom was observed in the granulosa cells of one selected antral follicle per case during the mid- to late proliferative period, and its immunointensity per granulosa cell in the follicle was not significantly different between mid- and late proliferative periods, although serum estradiol level was markedly elevated in the late proliferative period. In the luteal phase, both P450arom immunointensity per luteinized granulosa cell in a corpus luteum and serum estradiol level reached a peak in the mid-secretory period. These findings indicate that different factors may influence ovarian P450arom activity during the follicular and luteal phases, i.e., an increased number of granulosa cells in the selected follicle during the follicular phase but changes in P450arom activity per luteinized granulosa cell in the corpus luteum during the luteal phase.


1972 ◽  
Vol 71 (4) ◽  
pp. 755-764 ◽  
Author(s):  
William T. K. Bosu ◽  
Tore H:son Holmdahl ◽  
Elof D. B. Johansson ◽  
Carl Gemzell

ABSTRACT Concentrations of oestrogens*, progesterone and 17α-hydroxyprogesterone were determined in daily peripheral plasma samples during one normal menstrual cycle in eight rhesus monkeys. The oestrogens were measured by a rapid radioimmunoassay. Progesterone and 17α-hydroxyprogesterone were determined by competitive protein binding techniques subsequent to column separation on hydrophobic Sephadex. Oestrone and oestradiol in pooled plasma samples were determined by radioimmunoassay after column chromatography. The plasma concentration of oestrogen showed a gradual late follicular rise to a midcyclic peak followed by an abrupt fall for 1–2 days and a subsequent small rise to concentrations similar to those preceding the mid-cyclic peak. Plasma levels of progesterone were below 1 ng per ml before the mid-cyclic peak of oestrogens but rose significantly one day after the oestrogen peak, and reached a luteal plateau (range 3.4–11.3 ng per ml) five to six days later. The plasma levels of 17α-hydroxyprogesterone increase paralleled the mid-cyclic peak of oestrogens. The luteal phase pattern of 17α-hydroxyprogesterone mirrored the progesterone pattern, but the concentration was somewhat lower than for progesterone. All three steroid hormones measured decreased prior to the onset of the menstrual bleeding. Oestradiol (2.4–6.9 ng per 100 ml) dominated over oestrone (1–3.2 ng per 100 ml) in the follicular phase while the reverse was true during the luteal phase. The ratio of E2:E1 was 2:1 or higher in the follicular phase, but during the late luteal phase the ratio was reversed. The patterns of the three steroid hormones observed during the menstrual cycle were qualitatively similar to those reported in women, but quantitatively the oestrogen and progesterone levels were lower, while the levels of 17α-hydroxyprogesterone were higher in the rhesus monkey.


Author(s):  
Shehnaz Shaikh

Introduction: Menstrual cycle or menstruation involved discharge of sanguinous fluid and a sloughing of uterine wall. In women menstruation occurs at regular intervals on an average of 28 days, although most women gave a history of regular intervals of 28 to 30 days. About 10% -15% of women showed cycle at the precise 28 ± 2 days intervals when menstrual calendar was utilized. Normally in young women in different phases of ovarian cycles the plasma levels of estrogen vary. Ovulation occurs in the first 12-13th day of menstrual cycle, which is termed estrogen surge and second occurs in mid-luteal phase. During mid cycle or follicular phase of menstrual cycle the plasma concentration of progesterone is very low about 0.9 ng/mL. its level starts rising owing to secretion from the granulose cells. During luteal phase progesterone level reaches its peak value of 18 ng/mL and its level fall to a minimum value toward the end of the cycle. Estrogen affects local and systemic vasodilation. The menstrual cycle envelops two fundamental stages, the follicular stage (FP) and the luteal stage (LP). The follicular stage can part advance into two substages; the early FP, which is characterised with moo concentrations of both the key hormones estrogen and progesterone; and the mid FP where estrogen is tall autonomously from progesterone. The LP is epitomized by tall concentration of both estrogen and progesterone. These two fundamental stages are isolated by a soak surge in luteinizing hormone activating ovulation. These recurrent changes are said to be frequency unsurprising while long time. Aim: The main aim of this study is to evaluate the Cardiorespiratory functions changes during different Phases of Menstrual Cycle.   Material and methods: In this study, 20 with normal weight, 20 with obese and 20 with overage were included and taken them as a sample size. In this study all the young women those were recruited as a sample size are unmarried, undergraduate female student with the between the age group of 18-22years, having regular 28+6 days menstrual cycle for at least last 6months prior to this study. For the collection of data all the participants were instructed to attend the physiology lab department during each of three different phases. Day-2 during menstrual phase, Day-7, during follicular phase and Day-22 during luteal phase and the following parameters were recorded as Anthropometric measurements, measuring of pulse rate and blood pressure and cardiac efficiency test. Result: In general, work out proficiency changed essentially amid the distinctive stages of the menstrual cycle with the most elevated amid luteal stage and least amid menstrualo stage. There was no critical contrast in impact test amid menstrual stage, follicular stage and luteal stage of menstrual cycle among three bunches of people. Conclusion: We have watched noteworthy increment in cardiac and respiratory proficiency within the luteal stage of the menstrual cycle in ordinary weight people. Lower wellness levels were watched in overweight and stout females. In this manner hone of customary work out and admissions of solid slim down which offer assistance in lessening the weight and in turn the BMI will offer assistance in improving the physical wellness of the people. Keywords: Cardiorespiratory, Menstrual cycle, expiratory blast test


Author(s):  
Hannah N. Willett ◽  
Kristen J. Koltun ◽  
Anthony C. Hackney

This study examined the effect of estradiol-β-17 across the menstrual cycle (MC) during aerobic exercise on energy substrate utilization and oxidation. Thirty-two eumenorrheic (age = 22.4 ± 3.8 y (mean ± SD)), physically active women participated in two steady-state running sessions at 65% of VO2max, one during the early follicular and one during the luteal phase of the MC. Blood samples were collected at rest before each exercise session and analyzed for Estradiol-β-17 to confirm the MC phase. Carbohydrate (CHO) utilization and oxidation values were significantly lower (p < 0.05) in the luteal (utilization: 51.6 ± 16.7%; oxidation: 1.22 ± 0.56 g/min; effect size (ES) = 0.45, 0.27) than follicular phase (utilization: 58.2 ± 15.1%; oxidation: 1.38 ± 0.60 g/min) exercise sessions. Conversely, fat utilization and oxidation values were significantly (p < 0.05) higher in the luteal (utilization: 48.4 ± 16.7%; oxidation: 0.49 ± 0.19 g/min; ES = 0.45,0.28) than follicular phase (utilization: 41.8 ± 15.1%; oxidation: 0.41 ± 0.14 g/min). Estradiol-β-17 concentrations were significantly (p < 0.01) greater during the luteal (518.5 ± 285.4 pmol/L; ES = 0.75) than follicular phase (243.8 ± 143.2 pmol/L). Results suggest a greater use of fat and reduced amount of CHO usage during the luteal versus follicular phase, directly related to the change in resting estradiol-β-17. Future research should investigate the role these changes may play in female athletic performance.


1987 ◽  
Vol 116 (1) ◽  
pp. 145-149 ◽  
Author(s):  
Jocelyne Brun ◽  
Bruno Claustrat ◽  
Michel David

Abstract. Nocturnal urinary excretion of melatonin, LH, progesterone and oestradiol was measured by radioimmunoassay in nine normal women during a complete cycle. In addition, these hormonal excretions were studied in two women taking an oral contraceptive. A high within-subject coefficient of variation was observed for melatonin excretion in the two groups. In the nine normal cycling women, melatonin excretion was not decreased at the time of ovulation, but was significantly increased during the luteal phase compared with that of the follicular phase (P < 0.01). These data are consistent with a positive relationship between melatonin and progesterone during the luteal phase. In the two women under an oral contraceptive, melatonin excretion was found within the same range as for the other nine. The results are discussed in terms of pineal investigation in human.


1975 ◽  
Vol 64 (3) ◽  
pp. 555-571 ◽  
Author(s):  
K. P. McNATTY ◽  
W. M. HUNTER ◽  
A. S. McNEILLY ◽  
R. S. SAWERS

SUMMARY The concentrations of FSH, LH, prolactin, oestradiol and progesterone were measured in peripheral plasma and follicular fluid of women throughout the menstrual cycle. With the exception of prolactin, concentrations of pituitary and steroid hormones in follicular fluid correlated with those in peripheral plasma. Follicle-stimulating hormone was present in a greater number of small follicles ( < 8 mm) during or just after the peaks of FSH in peripheral plasma. During the mid-follicular phase the concentration of both FSH and oestradiol in fluid from large follicles ( ≥ 8 mm) was high. During the late follicular phase the large follicles ( ≥ 8 mm) contained high amounts of progesterone in addition to oestradiol, low physiological levels of prolactin, and concentrations of LH and FSH about 30 and 60% respectively of those found in plasma. By contrast no large 'active' follicles ( ≥ 8 mm) were found during the luteal phase although many contained both LH and FSH. Luteinizing hormone was present in a proportion of small follicles ( < 8 mm) during the late follicular and early luteal but not at other stages of the menstrual cycle. It is suggested that a precise sequence of hormonal changes occur within the microenvironment of the developing Graafian follicle; the order in which they occur may be of considerable importance for the growth of that follicle and secretory activity of the granulosa cells both before and after ovulation.


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