Control of pregnancy, parturition and luteolysis in marsupials

1990 ◽  
Vol 2 (5) ◽  
pp. 535 ◽  
Author(s):  
LA Hinds
Keyword(s):  
Life Span ◽  
Corpus Luteum ◽  
Post Partum ◽  
Secretory Activity ◽  
Extrinsic Factors ◽  
Pituitary Prolactin

In most eutherian species the function of the corpus luteum (CL) is influenced by extrinsic factors and it is subordinate to the pituitary, placenta, or uterus. In contrast, in marsupials the CL is relatively autonomous. Although the pituitary is essential for the formation of the CL, thereafter the secretory activity of the CL is independent of luteotrophic support, and the uterus is not luteolytic. Furthermore, the life span of the CL is unaffected by pregnancy, except in the Macropodidae (kangaroos and wallabies), in which the secretory activity of the CL is shortened under the influence of the fetus. At parturition the macropodid fetus, possibly via a release of glucocorticoids, causes the release of prostaglandins, presumed to be of uterine origin. The effect of the prostaglandin is to induce the release of prolactin from the maternal pituitary. Prolactin, and not prostaglandin, induces luteolysis and advances the events of post-partum oestrus. In the non-pregnant cycle, the mechanism of luteolysis is different; it does not involve prolactin, and the luteolytic signal is of non-uterine, possibly intrinsic, origin.

scholarly journals Uterine Notch2 facilitates pregnancy recognition and corpus luteum maintenance via upregulating decidual Prl8a2

PLoS Genetics ◽  
2021 ◽  
Vol 17 (8) ◽  
pp. e1009786
Author(s):  
Haili Bao ◽  
Yang Sun ◽  
Ningjie Yang ◽  
Na Deng ◽  
Zhangli Ni ◽  
...  
Keyword(s):  
Notch Signaling ◽  
Corpus Luteum ◽  
Convincing Evidence ◽  
Progesterone Level ◽  
Dopamine Receptor Agonist ◽  
Serum Progesterone ◽  
Pregnancy Recognition ◽  
Pituitary Prolactin ◽  
In Pregnancy

The maternal recognition of pregnancy is a necessary prerequisite for gestation maintenance through prolonging the corpus luteum lifespan and ensuring progesterone production. In addition to pituitary prolactin and placental lactogens, decidual derived prolactin family members have been presumed to possess luteotropic effect. However, there was a lack of convincing evidence to support this hypothesis. Here, we unveiled an essential role of uterine Notch2 in pregnancy recognition and corpus luteum maintenance. Uterine-specific deletion of Notch2 did not affect female fertility. Nevertheless, the expression of decidual Prl8a2, a member of the prolactin family, was downregulated due to Notch2 ablation. Subsequently, we interrupted pituitary prolactin function to determine the luteotropic role of the decidua by employing the lipopolysaccharide-induced prolactin resistance model, or blocking the prolactin signaling by prolactin receptor-Fc fusion protein, or repressing pituitary prolactin release by dopamine receptor agonist bromocriptine, and found that Notch2-deficient females were more sensitive to these stresses and ended up in pregnancy loss resulting from abnormal corpus luteum function and insufficient serum progesterone level. Overexpression of Prl8a2 in Notch2 knockout mice rescued lipopolysaccharide-induced abortion, highlighting its luteotropic function. Further investigation adopting Rbpj knockout and DNMAML overexpression mouse models along with chromatin immunoprecipitation assay and luciferase analysis confirmed that Prl8a2 was regulated by the canonical Notch signaling. Collectively, our findings demonstrated that decidual prolactin members, under the control of uterine Notch signaling, assisted pituitary prolactin to sustain corpus luteum function and serum progesterone level during post-implantation phase, which was conducive to pregnancy recognition and maintenance.

A STUDY OF PROLACTIN-LIKE ACTIVITY IN INDIVIDUAL HUMAN PITUITARY GLANDS

1970 ◽  
Vol 48 (4) ◽  
pp. 639-647 ◽  
Author(s):  
PATRICIA M. NICHOLSON
Keyword(s):  
Growth Hormone ◽  
Gel Electrophoresis ◽  
Anterior Pituitary ◽  
Post Partum ◽  
Human Pituitary ◽  
Lactating Women ◽  
Pituitary Glands ◽  
Human Anterior Pituitary ◽  
Pituitary Prolactin ◽  
Individual Human

SUMMARY Polyacrylamide disc gel electrophoresis of aqueous extracts of individual human anterior pituitary glands failed to identify a protein with lactogenic activity which was characteristic of pregnancy and the post-partum period. Lactogenic activity, determined by a semi-quantitative rabbit mammary gland organ culture assay, was largely associated with the growth hormone fraction. The total prolactin activity of individual anterior pituitary glands was determined by a 'local' intradermal pigeon crop sac method. The glands from pregnant and parturient women did not contain a higher concentration of prolactin than those of men or non-pregnant non-lactating women. These results do not provide any evidence for the existence of a human pituitary prolactin distinct from growth hormone. Reasons for this are discussed.

Breeding Biology of Brushtail Possums Trichosurus vulpecula (Marsupialia, Phalangeridae) in Captivity.

1995 ◽  
Vol 18 (1) ◽  
pp. 1
Author(s):  
R.T. Gemmell
Keyword(s):  
Body Weight ◽  
Life Span ◽  
Post Partum ◽  
Young Female ◽  
Brushtail Possum ◽  
Lactation Period ◽  
In Captivity ◽  
In The Wild ◽  
The Mean ◽  
Reproductive Capability

The brushtail possum is a common arboreal marsupial that is well adapted to the Australian urban environment and to rearing in captivity. Data obtained from 100 female possums housed in a semi-captive colony over a 7 year period demonstrate the reproductive capability of this marsupial. The main breeding season is from March to June with a declining number of births occurring from July to October. The possums gave birth to 259 single young and one set of twins. The range of the lactation period was from 177 to 200 days with the birth of the subsequent young occurring at 188.4 ± 4.1 days post partum (SD, n = 5). The growth rate of the young female possum varied greatly after day 100 post partum, the mean body weight of possums at day 172, being 753.0 ± 76.2g (SD, n = 5) with a range of 685 to 851 g. Female possums, with a mean body weight of 2171 ± 388g, gave birth to their first litter on day 345.9 ± 69.3 days postpartum (mean, SD, n = 7). Although two female possums trapped in the wild were held in captivity for 64 and 63.4 months and one possum bred in captivity had a life span of 51.5 months, the mean life span was 21.0 ± 12.5 months (SD, n =3D 8), with a range of 14.3 to 51.5 months. This life span is very variable and it is of interest to determine if this is an artefact of captivity or is also observed in the wild.

Reproduction of the Red-Bellied Pademelon Thylogale billardierii (Marsupialia)

1982 ◽  
Vol 9 (1) ◽  
pp. 27 ◽  
Author(s):  
RW Rose ◽  
DJ McCatney
Keyword(s):  
Corpus Luteum ◽  
Post Partum ◽  
Oestrous Cycle ◽  
Seasonal Breeder ◽  
The Mean ◽  
Duration Of Gestation

'Thylogale billardierii, which is abundant in Tasmania, is a seasonal breeder with most births in the months April, May and June. Parturition is followed by mating, and the zygote so produced remains dormant until either sucking becomes intermittent near the end of pouch life or the young is lost. The mean length of the oestrous cycle was determined at 30.3 days, not significantly longer than the duration of gestation (30.2 days). Removal of pouch young results in the birth of a new young 28.7 days later. Removal of the corpus luteum results in oestrus 11 days later. Pouch life is 202 days, and vacation of the pouch by the young coincides precisely with parturition and post-partum mating. The young mature at about 14-15 months.

Comparison of reproductive responses after PGF2α and GnRH-PGF2α oestrous synchronisation schemes in Holstein cows

2001 ◽  
Vol 26 (2) ◽  
pp. 467-470
Author(s):  
J.F. Cox ◽  
F. Saravia ◽  
O. Torrealba ◽  
A. Zavala ◽  
A. Lobos
Keyword(s):  
Dairy Cows ◽  
Corpus Luteum ◽  
Detection Efficiency ◽  
Post Partum ◽  
Conception Rate ◽  
Milk Samples ◽  
Reproductive Response ◽  
Holstein Friesian ◽  
Breeding Schemes ◽  
Friesian Cows

AbstractControlled breeding schemes for oestrous detection constitutes a proactive technical response that balances the infrastructural requirement for a profitable dairy operation and the demands for optimal animal performance. The present study compared (a) the reproductive response of a treatment based on a short vs longer-acting PGF2α analogue (tiaprost vs luprostiol), and (b) the reproductive response after a treatment of GnRH-PGF2α vs PGF2α alone for synchronizing dairy cows. Holstein-Friesian cows averaging 9000 kg milk/lactation and fed according to their requirements were used in the study. Cows were cyclic, at least 60 days post partum and were clinically sound before being considered for the experiments. In Experiment 1, animals were synchronised using an i.m. injection of either 15 mg of luprostiol or 0.75 mg of tiaprost, based on ultrasonic diagnosis of a corpus luteum. Animals were inseminated at observed oestrus. In Experiment 2, cows were synchronised, at random, by either an injection of 10pg ofbuserelin (day 0) followed by 0.75 mg of tiaprost at day 7 (GnRH-PGF2α) orjust 0.75 mg of tiaprost (PGF2α). For both treatments only cows with an ultrasonically detected corpus luteum were treated. Animals were inseminated at oestrus. At the time of treatment and again 3 days later, milk samples were collected and assayed for progesterone by RIA. Cows with progesterone concentrations >1 ng/ml were considered to have corpus luteum. Luteolysis was considered to have occurred when concentrations of progesterone were > 1 ng/ml at day 0 and <0.8 ng/ml at day 3. In Experiment 1, both analogues gave similar results in terms of induced luteolysis [luprostiol: 36/39 (92.3%) vs tiaprost: 36/41 (87.8%)], oestrous detection efficiency [luprostiol: 26/36 (72.2%) vs tiaprost: 30/36 (83.3%], oestrous distribution [day 2, 3 and 4, respectively: luprostiol: 26.9%, 50.0%, 19.2% vs tiaprost: 36.7%, 50.0%, 13.3%], and conception rates [luprostiol: 12/25 (48.0%) vs tiaprost: 14/28 (50.0%); P>0.05]. In Experiment 2, oestrous detection efficiency, interval to oestrus and conception rate were similar between treatments [97/149 (65.1%), 71.1 h, 43/95 (45.3%) for PGF2α vs 130/188 (69.1%), 68.2h, 65/126 (51.6%) for GnRH-PGF2α, respectively]. However the oestrous distribution was more concentrated in GnRH-PGF2α treated animals (P<0.01).

scholarly journals The development and morphology of the gonads of the mouse.— Part I. The morphogenesis of the indifferent gonad and of the ovary

1927 ◽  
Vol 101 (711) ◽  
pp. 391-409 ◽  
Keyword(s):  
Corpus Luteum ◽  
Sexual Maturity ◽  
Post Partum ◽  
Subsequent Paper ◽  
Adult Ovary

The work described in this series of papers was carried out with a view to furnishing controls of the experiments on the mouse undertaken in collaboration with Dr. A. S. Parkes and others. This paper deals with the development of the indifferent gonad of the mouse, up to the stage at which it differentiates into an ovary or a testis. This takes place on the 12th day post coitum , when the testis can first be distinguished. The ovaries remain in the indifferent stage for some time longer, but can be identified by a process of elimination. The present paper is concerned also with the development of the ovary from the time when sex can be distinguished until sexual maturity (8 weeks post partum ). It is not proposed to consider here the structure of the maturing follicle, the process of atresia, or the formation of the corpus luteum. These problems will be reserved for a subsequent paper on the adult ovary of the mouse.

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