Evidence for luteotrophic and antiluteolytic actions of prolactin in rats with 5-day oestrous cycles

1988 ◽  
Vol 117 (3) ◽  
pp. 455-460 ◽  
Author(s):  
J. E. Sánchez-Criado ◽  
P. van der Schoot ◽  
J. Th. J. Uilenbroek

ABSTRACT Injection of 1 mg bromocriptine at either 08.00 or 16.00 h on the day of oestrus in rats with 5-day oestrous cycles caused a reduction in the duration of progesterone secretion by the corpus luteum during dioestrous, and a shortening of the ovarian cycle by 1 day. These effects were not present when bromocriptine was injected at 08.00 h on the day of metoestrus. The effect of bromocriptine on progesterone secretion by the corpus luteum was reversed by neutralization of the biological activity of LH at dioestrus by injection of 0·5 ml anti-LH serum at 08.00 h at metoestrus. Injection of the antiserum alone prolonged progesterone secretion by the corpus luteum, but had no effect on the length of dioestrus. These results are interpreted as suggesting (1) that prolactin secretion on the afternoon of oestrus protects the corpus luteum of the rat ovarian cycle against the luteolytic effects of LH secretion during early dioestrus and (2) that prolactin stimulates progesterone secretion in the absence of such a luteolytic action. This response of the corpus luteum of the rat ovarian reproductive cycle to prolactin results in 5-day oestrous cycles. J. Endocr. (1988) 117, 455–460

1992 ◽  
Vol 132 (1) ◽  
pp. 115-122 ◽  
Author(s):  
J. E. Sánchez-Criado ◽  
J. Th. J. Uilenbroek ◽  
B. Karels

ABSTRACT Administration of the antiprogesterone RU486 (2 mg/day) for 14 days to rats with a 5-day reproductive cycle resulted in an increase in both ovarian and pituitary weight in contrast with rats with a 4-day oestrous cycle. Luteal progesterone production decreased earlier in 4-day than in 5-day cyclic rats. Treatment of 5-day cyclic rats with antiprogesterone from the day of metoestrus onwards resulted in the advancement of the preovulatory prolactin surge by 24 h. Progesterone production by the corpus luteum was, however, not affected, indicating that in 5-day cyclic rats the corpora lutea are still functionally active at the time of the preovulatory surge of prolactin. They become, therefore, stimulated both in size and progesterone production. In contrast, the corpora lutea in 4-day cyclic rats are functionally inactive at the time of the preovulatory surge of prolactin, and prolactin acts luteolytically. In conclusion, the advancement of the preovulatory surge of prolactin by 24 h accounts, at least in part, for the increase in ovarian weight in 5-day cyclic rats after treatment with antiprogesterone. The results of these experiments do not agree with a direct effect of the antiprogesterone RU486 on progesterone secretion by the corpus luteum. Journal of Endocrinology (1992) 132, 115–122


2021 ◽  
pp. 89-97
Author(s):  
I. A. Ivanov

It is well known that corpus luteum normal functioning is crucial for the luteal phase, which determines the embryo implantation and the progression of pregnancy. Luteal phase deficiency (LPD), associated with impaired progesterone secretion by the corpus luteum, is considered as a significant factor of infertility and early pregnancy loss, both in the natural cycle and in assisted reproductive technology (ART) programs. The LPD formation is associated with hypothalamic-pituitary-ovarian axis dysregulation, which leads to abnormal secretion of FSH, LH, ovulation and luteinization disorders, premature luteolysis. The most significant problem in the study of LPD is the lack of reliable and reproducible methods of its verification. This review summarizes the available data on the methods and issues of LPD diagnosing, including the duration of the luteal phase, the level of progesterone secretion, and endometrial biopsy. LPD is an important factor in reproductive failures during IVF, which is caused by suppression of the physiological FSH, LH secretion and requires mandatory progesterone support in the luteal phase of the cycle. It’s hard to define the contribution of LPD to miscarriage, however, empirical progestogen therapy may increase the live births rate in women with recurrent pregnancy loss. Currently, there is no evidence of the LPD role and progesterone support effectiveness in infertility management, so the diagnosis and therapy of LPD among these patients should not be considered.


1967 ◽  
Vol 55 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Benno Runnebaum ◽  
Josef Zander

ABSTRACT Progesterone was determined and identified in human peripheral blood during the preovulatory period of the menstrual cycle, by combined isotope derivative and recrystallization analysis. The mean concentration of progesterone in 1.095 ml of plasma obtained 9 days before ovulation was 0.084 μg/100 ml. However, the mean concentration of progesterone in 1.122 ml of plasma obtained 4 days before ovulation was 0.279 μg/100 ml. These data demonstrate a source of progesterone secretion other than the corpus luteum. The higher plasma-progesterone concentration 4 days before ovulation may indicate progesterone secretion of the ripening Graafian follicle of the ovary.


1987 ◽  
Vol 116 (3_Suppl) ◽  
pp. S111-S112 ◽  
Author(s):  
G.E. WEBLEY ◽  
J.P. HEARN ◽  
M.R. LUCK

1985 ◽  
Vol 107 (1) ◽  
pp. 31-39 ◽  
Author(s):  
L. Martinet ◽  
D. Allain ◽  
Y. Chabi

ABSTRACT In mink, termination of the delayed implantation period, following reactivation of the corpora lutea, and onset of the spring moult are associated with a rise in prolactin secretion triggered by increasing daylength, while decreasing daylength induces the autumn moult. To establish whether suppression of the function of the pineal rendered the mink unresponsive to daylength changes, the superior cervical ganglion was removed bilaterally 2–4 weeks before mating. Intact and operated females were then left outdoors or were put under a lighting regime of either 15 h light: 9 h darkness (15L: 9D) or 8L: 16D. In July, at the end of the spring moult, the 15L: 9D lighting regime was changed to one of 8L: 16D. Under artificial photoperiods ganglionectomy suppressed the stimulatory role of long days and the inhibitory role of short days on prolactin secretion, and consequently on progesterone secretion and spring moult. Neither was the autumn moult, induced early in intact females by the change to a short photoperiod, advanced in ganglionectomized females, showing that the latter were unresponsive to the artificial modification of the photoperiod. However, in animals kept outdoors, prolactin and progesterone secretion and spring moult were not changed by ganglionectomy. Increase in body weight and autumn moult were only slightly delayed by the operation suggesting that other environmental factors had replaced the synchronizing effect of the daylength changes. Alternatively the desynchronization between intact females responsive to photoperiodism and those rendered unresponsive may be too slow to be observed soon after ganglionectomy. J. Endocr. (1985) 107, 31–39


1986 ◽  
Vol 111 (4) ◽  
pp. 553-557 ◽  
Author(s):  
Inese Z. Beitins ◽  
Maria L. Dufau

Abstract. Having previously established that biologically active luteinizing hormone (LH) is secreted in episodic pulsations that vary in relation to the menstrual cycle, we investigated the possibility that a temporal relationship could exist between the bioactive LH pulses and progesterone secretion from the late corpus luteum. In 4 young women blood was withdrawn every 15 min for 8 h. Serum progesterone concentrations fluctuated at a mean frequency of 0.9 h with a wide range of amplitudes (13.8 to 1.7 ng/ml). Serum bioactive LH pulse frequency in contrast was 0.25 pulses/h in all subjects. The pulse amplitude was 18.2 to 12.4 mIU/ml (2nd IRP-hMG). These data reveal that within the 8 h-period studied, progesterone secretory pulses occurred four times more frequently as those for bioactive LH. Therefore it is unlikely that a temporal relationship exists between individual bioactive LH and pulses of progesterone secreted by the late corpus luteum.


1987 ◽  
Vol 112 (2) ◽  
pp. 317-322 ◽  
Author(s):  
J. E. Sánchez-Criado ◽  
K. Ochiai ◽  
I. Rothchild

ABSTRACT Adult female rats were hypophysectomized and their pituitary glands autotransplanted beneath the left kidney capsule on day 2 (day 1 was the day of ovulation). In such rats the pituitary secretes prolactin fairly constantly and the corpora lutea secrete progesterone for several months. To induce the luteolytic effect of prolactin the rats were first injected s.c. with 2-bromo-α-ergocryptine (CB-154) on cycle days 12, 13 and 14 (i.e. 10, 11 and 12 days after operation) to depress prolactin secretion, and then with CB-154 vehicle (70% ethanol) daily until cycle day 21, to allow prolactin secretion to resume. One ovary was removed from each rat on day 15 and the remaining one on day 22. The mean (± s.e.m.) weight of the corpora lutea on day 15 was 1·46±0·06 mg and 0·98±0·07 mg on day 22 (n = 17). In contrast, rats in which the CB-154 treatment was maintained to day 21 had corpora lutea which weighed 1·31 ±0·09 on day 15 and 1·47 ±0·08 mg on day 22 (n = 15). To investigate whether indomethacin, a prostaglandin synthesis inhibitor, affected the luteolytic action of prolactin, the experiment was repeated, but on day 15 (after the removal of one ovary) the groups in which CB-154 treatment was stopped, as well as the group in which CB-154 treatment was maintained, were each divided into two groups. In one, indomethacin-containing silicone elastomer wafers and, in the other, blank silicone elastomer wafers, were placed within the bursa of the remaining ovary. There were no differences in corpus luteum weight on day 15 among any of these groups and the two groups of the first experiment. There was no significant difference in corpus luteum weight between day 15 and day 22 in any of the six groups except for the two groups treated with the CB-154 vehicle and not with indomethacin. Thus, treatment with indomethacin prevented the fall in corpus luteum weight associated with the discontinuation of CB-154 treatment. Serum prolactin levels fell until day 15 in all rats and remained low in those in which the CB-154 treatment was maintained to day 21, but returned to control values in those treated with vehicle after day 14. Serum progesterone levels fell and remained low in all groups. Indomethacin treatment had no effect on the levels of either serum prolactin or progesterone. We conclude that some of the pharmacological effects of indomethacin are to prevent prolactin-induced luteolysis, and we suggest that prolactin induces rapid regression of the corpus luteum by stimulating intraluteal prostaglandin production or by being necessary for the effect of luteolytic prostaglandins. J. Endocr. (1987) 112, 317–322


2019 ◽  
Vol 19 (2) ◽  
pp. 107-112
Author(s):  
Budianto Panjaitan ◽  
Citra Chyntia Helwana ◽  
Nellita Meutia ◽  
Yusmadi Yusmadi ◽  
Tongku Nizwan Siregar ◽  
...  

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.


Reproduction ◽  
2001 ◽  
pp. 643-648 ◽  
Author(s):  
A Shaham-Albalancy ◽  
Y Folman ◽  
M Kaim ◽  
M Rosenberg ◽  
D Wolfenson

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.


2002 ◽  
Vol 55 (1-2) ◽  
pp. 11-20 ◽  
Author(s):  
Luigi Devoto ◽  
Margarita Vega ◽  
Paulina Kohen ◽  
Olga Castro ◽  
Pilar Carvallo ◽  
...  

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