Developement, function and regression of the corpus luteum in the marsupial Trichosurus vulpecula

1973 ◽  
Vol 21 (4) ◽  
pp. 477 ◽  
Author(s):  
CD Shorey ◽  
RL Hughes
Keyword(s):  
Corpus Luteum ◽  
Luteal Phase ◽  
Secretory Activity ◽  
Oestrous Cycle ◽  
Secretion Rate ◽  
Trichosurus Vulpecula ◽  
Progesterone Concentration ◽  
Apparent Increase ◽  
Pregnant Females ◽  
Secretion Rates

Following ovulation, which usually takes place on day 1 of the 26-day oestrous cycle in T. culpecula, a single corpus luteum begins to develop. During the period before the uterine luteal phase begins on day 8 of the cycle, the granulosa lutein cells are active in the synthesis of what appears to be a cholesterol-like substance at a time when the ovarian secretion rates of progesterone are re!atively low. The uterine luteal phase extends from day 8 to day 15 of the cycle. During this phase the ovarian secretion rates of progesterone are relatively high, and reach maximal levels on days 12-1 3. This high secretory activity is manifested in the granulosa lutein cells by an apparent increase in the number of mitochondria, thought to be involved with the conversion of intracellularly stored cholesterol to pregnenolone, and the development of whorl-like configurations of agranular reticulum which are reported to be concerned with the conversion of pregnenolone to progesterone. A drop in progesterone concentration commences in pregnant and non-pregnant females on day 17 of the cycle, when early involution of the corpus luteunl is apparent. By day 20, the corpus luteum regresses to an early corpus albicans, and the ovarian secretion rate of progesterone falls progressively to levels similar to those in anoestrous females.

REPRODUCTION IN THE MARSUPIAL TRICHOSURUS VULPECULA

1962 ◽  
Vol 25 (1) ◽  
pp. 119-NP ◽  
Author(s):  
PHYLLIS E. PILTON ◽  
G. B. SHARMAN
Keyword(s):  
Corpus Luteum ◽  
Luteal Phase ◽  
Oestrous Cycle ◽  
Gestation Period ◽  
Gravid Uterus ◽  
Corpora Lutea ◽  
Trichosurus Vulpecula ◽  
Vaginal Smears ◽  
Pregnant Females

SUMMARY Most, or all, wild females of Trichosurus vulpecula bred during the first 6 months of the year and some bred again during the second half of the year. In captive females the oestrous cycle varied in length from 22 to 58 days but all cycles longer than 32 days began between 20 April and 16 June. During two periods of each year, from early February until 20 April and from 16 June until late September, the cycle varied in length from 22 to 32 days (mean: 25·69±0·31 days). The females were polyoestrous and monovular and the gestation period was about 17·5 days. Vaginal smears from mated and non-mated females were alike except that spermatozoa were usually found in smears from mated females on the first or second day after copulation. After oestrus, ovulation and corpus luteum formation occurred alike in mated and non-mated females. There were no differences between corpora lutea of pregnant and non-pregnant females. After parturition oestrus was inhibited by the onset of lactation except in one female which produced two successive young separated in age by approximately the length of one oestrous cycle. Females came into oestrus an average of 8·02±0·18 days after removal of suckling young from the pouch. In pregnant females the gravid uterus was much larger than the non-gravid uterus from 12 days after oestrus until after parturition. The sub-epithelial capillary layer was better developed in the gravid than in the non-gravid uterus during the closing stages of pregnancy. The uterine luteal phase was present 7–8 days after oestrus and began to disappear at about 15 days after oestrus in both pregnant and non-pregnant females. There was no evidence that the luteal phase was longer in pregnant than in non-pregnant females and the occurrence of pregnancy did not extend the normal interval between successive oestrous periods if the young were removed at birth.

Source of ovarian inhibin secretion during the oestrous cycle of the sheep

1989 ◽  
Vol 123 (2) ◽  
pp. 181-188 ◽  
Author(s):  
G. E. Mann ◽  
A. S. McNeilly ◽  
D. T. Baird
Keyword(s):  
Corpus Luteum ◽  
Luteal Phase ◽  
Venous Blood ◽  
Contralateral Side ◽  
Follicular Phase ◽  
Oestrous Cycle ◽  
Secretion Rate ◽  
Antral Follicles ◽  
Luteal Tissue

ABSTRACT The source of inhibin secretion by the ovary in the sheep at different stages of the oestrous cycle was investigated by in-vivo cannulation of the ovarian veins. Twenty-four Scottish Blackface ewes were allocated to four groups of six ewes, i.e. those operated on during the luteal phase (day 10), and those operated on during the follicular phase 24–30, 36 and 60 h following an injection of 125 μg cloprostenol on day 10 of the luteal phase. Samples of jugular and timed ovarian venous blood were collected under anaesthesia before and after enucleation of the corpus luteum. Ovaries were then removed and follicles dissected out. Following injection of cloprostenol, luteal regression occurred as indicated by a fall in the secretion of progesterone. The concentration of inhibin in jugular venous plasma and its ovarian secretion rate were similar at all stages of the follicular phase and during the luteal phase. In contrast, the secretion rate of oestradiol rose from 2·68 ±0·73 pmol/min during the luteal phase to 8·70± 2·24 pmol/min 24 h after injection of cloprostenol (P<0·05). Following enucleation of the corpus luteum the secretion rate of progesterone fell from 809 ± 270 pmol/min to 86 ± 30 pmol/min (P<0·001). There was also a smaller, artifactual fall in the secretion rate of oestradiol following enucleation of the corpus luteum, which was of similar size to a fall seen in the secretion rate of inhibin. This resulted in a significant (P<0·001) fall in the ratio of progesterone to inhibin, while the oestradiol to inhibin ratio remained unchanged. The secretion rate of inhibin from ovaries containing luteal tissue was similar to that from the contralateral side without luteal tissue (1·41±0·30 compared with 1·32±0·30 ng/min), while ovaries with large antral follicles secreted significantly (P< 0·001) more inhibin than those with no follicles ≥3 mm (2·28 ± 0·36 compared with 0·25 ±0·06 ng/min). From these results we conclude that, in the sheep, large antral follicles are responsible for most, if not all, the secretion of inhibin by the ovary at all stages of the oestrous cycle, and that the corpus luteum secretes little or no immunoactive or bioactive inhibin. Due to the fact that, unlike inhibin, the secretion rate of oestradiol rises during the follicular phase of the cycle, when the concentration of FSH is suppressed, it seems likely that oestradiol rather than inhibin is the major ovarian factor modulating the change in FSH secretion seen at this stage of the oestrous cycle. Journal of Endocrinology (1989) 123, 181–188

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.

scholarly journals Hubungan Kadar Progesteron pada Fase Awal Luteal dengan Kematian Embrio pada Sapi Aceh

2019 ◽  
Vol 19 (2) ◽  
pp. 107-112
Author(s):  
Budianto Panjaitan ◽  
Citra Chyntia Helwana ◽  
Nellita Meutia ◽  
Yusmadi Yusmadi ◽  
Tongku Nizwan Siregar ◽  
...  
Keyword(s):  
Body Weight ◽  
Corpus Luteum ◽  
Adult Female ◽  
Artificial Insemination ◽  
Luteal Phase ◽  
Embryonic Mortality ◽  
Progesterone Concentration ◽  
Double Injection ◽  
Progesterone Secretion ◽  
Embryonic Death

ABSTRAK.  Progesteron merupakan hormon yang berperan penting dalam proses pemeliharaan kebuntingan dan dihasilkan oleh corpus luteum. Penelitian ini bertujuan mengetahui hubungan antara kadar hormon progesteron pada fase awal luteal dengan kematian embrio pada sapi Aceh. Dalam penelitian ini digunakan empat ekor sapi betina dewasa berumur 3-5 tahun, bobot badan 150-250 kg, sehat secara klinis, dan memiliki reproduksi normal. Sapi disinkronisasi menggunakan 5 ml prostaglandin F2 alfa (PGF2α) dengan pola penyuntikan ganda berinterval 11 hari. Koleksi sampel darah untuk pengukuran konsentrasi progesteron dilakukan pada hari ke-5, 6, dan 7 pasca inseminasi. Pengukuran konsentrasi progesteron dilakukan menggunakan metode enzymelinked-immunoassay (ELISA), pemeriksaan kebuntingan dan kematian embrio menggunakan metode transrektal ultrasonografi pada hari ke-25 pasca inseminasi. Pemeriksaan diulang setiap 10 hari sampai hari ke-55 pasca inseminasi. Puncak sekresi progesteron pada sapi bunting dengan embrio yang bertahan hidup terdapat pada hari ke-7 (2,082 ng/ml), pada sapi Late Embryonic Mortality (LEM) di hari ke-5 (8,209 ng/ml) dan pada sapi tidak bunting di hari ke-7 (3,051±1,157 ng/ml). Sekresi progesteron sapi LEM pada hari ke-5 sampai dengan ke-7 cenderung menurun sedangkan pada sapi yang bertahan hidup cenderung meningkat.  (Correlation between progesterone levels in early luteal phase and embryonic death  in Aceh cattle) ABSTRACT. Progesterone is an important hormone that functions to maintain pregnancy and is produced by the corpus luteum. The aim of this study was to see a correlation between progesterone and the incidence of embryonic death in Aceh cattle. This study used four adult female cows, 3-5 years old, 150-250 kg body weight, clinically healthy, and have a normal reproduction. The synchronized with 5 ml prostaglandin F2 alfa hormone, and double injection pattern with 11-day intervals. The blood was collected for progesterone measurements on 5th, 6th, 7th day post artificial insemination. Measurement of progesterone concentration was carried out using an enzymelinked-immunoassay (ELISA), while pregnancy and embryo mortality was performed using the trans-rectal ultrasonography method on the 25th day after insemination. The examination was repeated every 10 days until day 55th after insemination. Progesterone secretion peaks in pregnant cows were on day 7th (2.082 ng/ml), in cattle Late Embryonic Mortality (LEM) on day 5th (8.209 ng/ml) and in cattle not pregnant on day 7th (3.051±1.157 ng/ml). The pattern of LEM progesterone secretion on days 5th to 7th tends to decrease while those that survive tend to increase.

A comparative study of the corpus luteum

1995 ◽  
Vol 7 (3) ◽  
pp. 303 ◽  
Author(s):  
RT Gemmell
Keyword(s):  
Corpus Luteum ◽  
Luteal Phase ◽  
Secretory Granules ◽  
Hormonal Control ◽  
Egg Laying ◽  
Oestrous Cycle ◽  
Corpora Lutea ◽  
Embryonic Diapause ◽  
Alternative Reproductive Strategy ◽  
Uterine Development

The corpus luteum (CL) is a transitory organ which has a regulatory role in reproduction. Sharks, amphibians and reptiles have corpora lutea that produce progesterone which influences the rate of embryonic development. The egg-laying monotremes and the two major mammalian groups, eutherian and marsupial, have a CL that secretes progesterone. Most eutherians have allowed for the uterine development of their young by extending the length of the oestrous cycle and the CL or placenta actively secretes progesterone until birth. Gestation in the marsupial does not extend beyond the length of an oestrous cycle and the major part of fetal development takes place in the pouch. Where the extension of the post-luteal phase in the eutherian has allowed for the uterine development of young, the marsupial has extended the pre-luteal phase of the oestrous cycle and has evolved an alternative reproductive strategy, embryonic diapause. The mechanism for the secretion of hormones from the CL has been controversial for many years. Densely-staining secretory granules have been observed in the CL of sharks, marsupials and eutherians. These granules have been reported to contain relaxin, oxytocin or mesotocin, and progesterone. A hypothesis to suit all available data is that all hormones secreted by the CL are transported within such granules. In conclusion, although there are obvious differences in the mode of reproduction in the two main mammalian groups, it is apparent that there is a great deal of similarity in the hormonal control of regression of the CL and parturition.

scholarly journals Delayed effect of low progesterone concentrations on bovine uterine PGF(2alpha) secretion in the subsequent oestrous cycle

Reproduction ◽  
2001 ◽  
pp. 643-648 ◽  
Author(s):  
A Shaham-Albalancy ◽  
Y Folman ◽  
M Kaim ◽  
M Rosenberg ◽  
D Wolfenson
Keyword(s):  
Corpus Luteum ◽  
Luteal Phase ◽  
Oestrous Cycle ◽  
Delayed Effect ◽  
Plasma Progesterone ◽  
Progesterone Secretion ◽  
Progesterone Treatment ◽  
Late Luteal Phase ◽  
Subsequent Cycle ◽  
Concentration Curves

Low progesterone concentrations during the bovine oestrous cycle induce enhanced responsiveness to oxytocin challenge late in the luteal phase of the same cycle. The delayed effect of low progesterone concentrations during one oestrous cycle on uterine PGF(2alpha) secretion after oxytocin challenge on day 15 or 16 of the subsequent cycle was studied by measuring the concentrations of the major PGF(2alpha) metabolite (13,14-dihydro-15-keto PGF(2alpha); PGFM) in plasma. Two experiments were conducted, differing in the type of progesterone treatment and in the shape of the low progesterone concentration curves. In Expt 1, progesterone supplementation with intravaginal progesterone inserts, with or without an active corpus luteum, was used to obtain high, or low and constant plasma progesterone concentrations, respectively. In Expt 2, untreated cows, representing high progesterone treatment, were compared with cows that had low but increasing plasma progesterone concentrations that were achieved by manipulating endogenous progesterone secretion of the corpus luteum. Neither experiment revealed any differences in plasma progesterone concentrations between the high and low progesterone groups in the subsequent oestrous cycle. In both experiments, both groups had similar basal concentrations of PGFM on day 15 (Expt 1) or 16 (Expt 2) of the subsequent oestrous cycle, 18 days after progesterone treatments had ended. In both experiments, the increases in PGFM concentrations in the low progesterone groups after an oxytocin challenge were markedly higher than in the high progesterone groups. These results indicate that low progesterone concentrations during an oestrous cycle have a delayed stimulatory effect on uterine responsiveness to oxytocin during the late luteal phase of the subsequent cycle. This resulting increase in PGF(2alpha) secretion may interfere with luteal maintenance during the early stages of pregnancy.

Cyclical changes in the uterine endometrium and peripheral plasma concentrations of progesterone in the marsupial Trichosurus vulepcula

1973 ◽  
Vol 21 (1) ◽  
pp. 1 ◽  
Author(s):  
CD Shorey ◽  
RL Hughes
Keyword(s):  
Blood Plasma ◽  
Peripheral Blood ◽  
Plasma Concentrations ◽  
Secretory Activity ◽  
Oestrous Cycle ◽  
Uterine Endometrium ◽  
Pregnant Females ◽  
Peripheral Plasma ◽  
Functional Differences ◽  
Peripheral Blood Plasma

The proliferation and secretory activity of the uterine endometrium in the marsupial T. vulpecula is examined at the cellular and subcellular levels throughout the 26-day oestrous cycle. The observations described are correlated with measured concentrations of progesterone in the peripheral blood plasma. Evidence cited indicates that there are no significant functional differences in the uterine endometrial secretory activity during the 17.5-day gestation period in pregnant females, compared with those in a normal oestrous cycle. Progesterone assays carried out on blood plasma taken from 20 staged animals throughout the oestrous cycle, five of which were at known stages of gestation, also supports the view that pregnancy does not significantly alter the physiological pattern of the reproductive cycle in this marsupial.

Ovarian secretion rates and peripheral concentrations of inhibin in normal and androstenedione-immune ewes with an autotransplanted ovary

1990 ◽  
Vol 127 (2) ◽  
pp. 285-296 ◽  
Author(s):  
B. K. Campbell ◽  
D. T. Baird ◽  
A. S. McNeilly ◽  
R. J. Scaramuzzi
Keyword(s):  
Luteal Phase ◽  
Venous Blood ◽  
Plasma Concentrations ◽  
Active Immunization ◽  
Follicular Phase ◽  
Secretion Rate ◽  
Luteal Function ◽  
Prostaglandin F ◽  
Ovarian Inhibin ◽  
Secretion Rates

ABSTRACT Active immunization of sheep against androstenedione results in an increase in ovulation rate that is associated with increased plasma levels of LH and progesterone, but not FSH. Although immunized ewes have more activated follicles the secretion rate of oestradiol is not increased. An experiment was conducted to examine the effect of androstenedione immunity on the ovarian secretion and peripheral plasma concentrations of inhibin. Merino ewes in which the left ovary had been autotransplanted to a site in the neck were divided into control (n = 5) and androstenedione-immune (n = 6) groups. Ovarian and jugular venous blood was collected every 10 min at two stages of the follicular phase, 21–27 h and 38–42 h after a luteolytic dose of an analogue of prostaglandin F2α (PG), and every 15 min for 6 h on day 10 of the subsequent luteal phase. The ewes were monitored regularly for luteal function by measurement of the concentration of progesterone and preovulatory LH surges. The concentration of inhibin in jugular and ovarian venous plasma was determined by radioimmunoassay and ovarian secretion rates and peripheral concentrations are expressed as pg of 1–26 peptide fragment of the α chain. The ovarian secretion rate of inhibin tended to be greater in androstenedione-immune ewes at all stages of the oestrous cycle measured, with this difference being statistically significant (P <0·05) during the luteal phase (100±40 and 260±80 (s.e.m.) pg/min for control and immune groups respectively). The pattern of ovarian inhibin secretion exhibited pulsatile-like fluctuations which were not associated with LH pulses. Peripheral concentrations of inhibin were generally higher in immunized than in control ewes with this difference being significant (P < 0·01) from day 4 to 14 of the luteal phase (59±5 and 110±7 ng/1 for control and immune respectively). The ovarian secretion rate of immunoactive inhibin was greater (P <0·01) during the follicular phase than during the luteal phase in both groups of ewes, and peripheral concentrations of inhibin increased (P < 0·001) following injection of PG in ewes from both treatment groups. We concluded that androstenedione immunity results in an increase in ovarian inhibin secretion, an effect that can probably be attributed to the greater number of large oestrogenic follicles present in the ovaries of these ewes. Furthermore, this increase in the concentration of inhibin may override any decrease in the negative feedback effects of ovarian steroid produced by immunization and, hence, explain the paradoxical findings of normal concentrations of FSH and raised concentrations of LH in ewes which are immunized against androstenedione. Journal of Endocrinology (1990) 127, 285–296

EFFECTS OF HUMAN CHORIONIC GONADOTROPHIN ON THE RELEASE OF CYCLIC AMP AND PROGESTERONE FROM THE SHEEP OVARY AT DIFFERENT STAGES OF THE OESTROUS CYCLE

1978 ◽  
Vol 89 (1) ◽  
pp. 158-165 ◽  
Author(s):  
T. J. Weiss ◽  
P. O. Janson ◽  
K. J. Porter ◽  
R. F. Seamark
Keyword(s):  
Cyclic Amp ◽  
Corpus Luteum ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Oestrous Cycle ◽  
Secretion Rate ◽  
Arterial Plasma ◽  
Venous Plasma

ABSTRACT The rate of release of cyclic AMP by sheep ovaries containing a corpus luteum was determined at different stages of the cycle before and up to 60 min after an intra-arterial (ia) injection of 500 IU human chorionic gonadotrophin (hCG). The median cyclic AMP concentration in arterial plasma and of ovarian venous plasma following hCG stimulation was 93.2 and 98.0 pmol/ml, respectively. The ovaries of ewes examined at Days 1 and 2 of the cycle showed no response to hCG, whereas in 2 sheep at Day 3, hCG caused a slight response, and in 13 sheep examined between Days 5–18, hCG caused a marked increase in cAMP release. In 5 of the sheep in which both ovarian veins were cannulated, only the ovary with a corpus luteum responded to hCG with an increased secretion rate of cyclic AMP and progesterone. The results indicate a lack of responsiveness in the newly formed corpus luteum to hCG.

CONCENTRATION OF PROSTAGLANDIN F2α AND STEROIDS IN THE HUMAN CORPUS LUTEUM

1977 ◽  
Vol 73 (1) ◽  
pp. 115-122 ◽  
Author(s):  
I. A. SWANSTON ◽  
K. P. McNATTY ◽  
D. T. BAIRD
Keyword(s):  
Menstrual Cycle ◽  
Corpus Luteum ◽  
Luteal Phase ◽  
Prostaglandin F2α ◽  
Corpora Lutea ◽  
Progesterone Concentration ◽  
Late Luteal Phase ◽  
Prostaglandin F ◽  
Human Corpus Luteum

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.

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