Effect of the conceptus on uterine prostaglandin-F2α and prostaglandin-E2 release and synthesis during the periimplantation period in the pig

2009 ◽  
Vol 21 (5) ◽  
pp. 709 ◽  
Author(s):  
Marta Wasielak ◽  
Katarzyna Kamińska ◽  
Marek Bogacki

The present study was conducted to evaluate the effect of the conceptus on uterine prostaglandin-F2α (PGF2α) and prostaglandin-E2 (PGE2) release and the expression of prostaglandin synthase enzymes during the periimplantation period in the pig. A surgically generated model with conceptuses developing in only one of the uterine horns was created. The highest concentration of PGF2α and PGE2 was found in the gravid uterine horn, compared with the non-gravid horn and the intact horn of cyclic gilts. Endometrial concentration of both PGs in pregnant gilts was elevated regardless of the conceptus in the uterine horn, whereas only myometrial PGE2 concentration increased during pregnancy. Expression of prostaglandin-E2 synthase (mPGES-1) mRNA in the endometrium was upregulated during the oestrous cycle, while protein expression presented a similar pattern to that of PGE2 concentration in the uterine flushings. Prostaglandin-F2α synthase (PGFS) mRNA and protein expression in the endometrium did not differ between pregnancy and oestrous cycle but PGFS mRNA in the myometrium increased during pregnancy both in the gravid and the non-gravid uterine horns. We suggest a local effect of the conceptus on PG release pathways but also a more systemic effect within the whole uterus with regard to PG synthesis and accumulation in uterine tissues.

2006 ◽  
Vol 188 (3) ◽  
pp. 569-577 ◽  
Author(s):  
A L Griffiths ◽  
K M Marshall ◽  
J Senior ◽  
C Fleming ◽  
D F Woodward

Previous studies in this laboratory have suggested that the isolated uterus from non-pregnant mice has a prostaglandin F and a thromboxane receptor population similar to that found in human myometrium. The aim of this study was to investigate any regional variation in myogenic activity ) and the and responsiveness to prostaglandin F2α (PGF2α thromboxane mimetic U46619 in the mouse uterus taken during different stages of the oestrous cycle and during pregnancy. Uterine samples from BKW mice were taken from different anatomical segments along the length of each uterine horn and set up for superfusion at 2 ml/min with Krebs solution (containing 1 μM indometacin) at 37 °C, and gassed with 95%O2/5%CO2. Responses (area under the curve) are expressed as a percentage of the final contraction induced by hypotonic shock. Data are expressed as the means ± s.e.m. of n=5–12 and were analysed using Student’s paired t-test or two-way ANOVA with a Bonferroni post hoc test. Regional variation in myogenic activity was observed in all tissues studied except those taken during labour. These tissues displayed significantly greater myogenic activity than tissues taken at late gestation and at all stages of the oestrous cycle. Tissues from pregnant animals were generally more responsive to U46619 and PGF2α than tissues taken from non-pregnant animals. Tissues taken from the upper segment of the uterine horn were more responsive to both agonists during the oestrous cycle. The findings demonstrated that the hormonal milieu and site of excision are important for myogenic activity and responsiveness.


Reproduction ◽  
2005 ◽  
Vol 130 (1) ◽  
pp. 105-112 ◽  
Author(s):  
Agnieszka Blitek ◽  
Adam J Ziecik

LH appears to be a potent stimulator of the release of endometrial prostaglandins (PGs) in the pig. The aim of the present studies was to examine the effect of LH on PGF2αand PGE2secretion by cultured porcine endometrial cells on days 10–12 and 14–16 of the oestrous cycle and to compare its action with oxytocin. A time-dependent effect of LH (10 ng/ml) on PGF2αrelease from luminal epithelial and stromal cells on days 10–12 was observed (experiment 1). The highest increase in PGF2αsecretion in response to LH was detected in stromal cells after 6 h of incubation (P< 0.001). Epithelial cells responded to LH after a longer exposure time (P< 0.01). A concentration-dependent effect of LH (0.1–100 ng/ml) on PGF2αrelease from stromal cells was examined after 6 h and from epithelial cells after 12 h (experiment 2). Effective concentrations of LH were 10 and 100 ng/ml. LH (10 ng/ml) and oxytocin (100 nmol/l) affected PGF2αand PGE2secretion from endometrial cells on days 10–12 and 14–16 of the oestrous cycle (experiment 3). LH stimulated PGF2αsecretion from both cell types and its action was more potent on days 10–12. LH induced PGE2release, especially in epithelial cells on days 14–16. A stimulatory effect of oxytocin on PGF2αwas confirmed in stromal cells, but this hormone was also shown to enhance PGE2output. These results indicated that LH, like oxytocin, a very effective stimulator of PGF2αrelease, could play an important role in the induction of luteolysis.


Author(s):  
Fabiana Fernandes Bressan ◽  
Claudia Maria Bertan Membrive ◽  
Marcelo Demarchi Goissis ◽  
Vanessa Belentani Marques ◽  
Pauline Martins da Cunha ◽  
...  

Prostaglandin F2α (PGF2α) determines luteolysis in cattle, and the ability to manipulate its endogenous synthesis is indispensible for large-scale animal breeding. Estradiol (E2) and progesterone (P4) modulate several molecular pathways in endometrial cells, including the synthesis of PGF2α; however, its specific mechanisms are still not totally known. This study investigated the production in vitro and possible modulation of endometrial PGF2α due to a local effect of endogenous E2 in the ipsilateral uterine horn (UH) containing the dominant follicle (DF) or from P4 in ipsilateral horn containing the corpus luteum (CL). The PGF2α stimulators oxytocin (OT) and phorbol 12,13-dibutyrate (PDBu) were incubated with endometrial explants, and PGF2α content was measured. For that, cycling cows were synchronized, the development of DF and CL was examined by ultrasonography and on the seventh day of the estrous cycle, endometrial explants were collected and cultured in medium supplemented with 10-6 M PDBu or 10-6 M OT or non-supplemented. Media samples were collected immediately after treatment and 60 min later. Radioimmunoassay showed that the PGF2α content of the UH ipsilateral to the DF was 49% less than that of the contralateral UH (8.22 ± 0.95 vs. 12.24 ± 0.95 pg/mL/mg tissue, respectively; P < 0.01). However, the PGF2α levels did not differ between the UHs as a function of the CL position (9.46 ± 0.95 vs. 11 ± 0.95 pg/mL/mg; P > 0.05). The cellular stimulators promoted an increase in PGF2α synthesis (P < 0.02), and the effects differed among the animals (P < 0.04). The PGF2a production was higher in the explants treated with PDBu rather than OT (13.68 ± 1.16 vs. 10.01 ± 1.16 pg/mL/mg tissue, respectively; P < 0.05). In conclusion, PGF2α synthesis is modulated by the presence of the DF (local E2) but not the CL (local P4), and both PDBu and OT stimulated PGF2a synthesis.


Reproduction ◽  
2015 ◽  
Vol 149 (4) ◽  
pp. 317-327 ◽  
Author(s):  
Martyna Łupicka ◽  
Gabriel Bodek ◽  
Nahum Shpigel ◽  
Ehud Elnekave ◽  
Anna J Korzekwa

The aim of this study was to identify uterine pluripotent cells both in bovine uterine tissues as well in epithelial, stromal, and myometrial uterine cell populations. Moreover, the relationship of pluripotent markers expression with age and the uterine horn side was considered. Uterine tissue was collected from ipsilateral and contralateral horns (days 8–10 of the estrous cycle). Immunohistostaining for C-KIT, OCT3/4, NANOG, and SOX2 in uterine tissue was determined. mRNA expression of C-KIT, OCT3/4, NANOG and SOX2 was evaluated in uterine tissue relative to the age of the cow and uterine horn side. Gene and protein expression of these markers in the uterine luminal epithelial, stromal, and myometrial cells was evaluated by real-time PCR and western blotting respectively. The expression of pluripotent cell markers OCT3/4, NANOG, and SOX2 was identified by flow cytometry assay in epithelial, stromal, and myometrial cells. Multilineage differentiation of the bovine uterine cells was performed. mRNA expression of OCT3/4, NANOG, and SOX2 in uterine tissue was higher in the ipsilateral horn than in the contralateral horn. Flow cytometry assay revealed positive fluorescence for OCT3/4, NANOG, and SOX2 in all uterine cell types. Results showed the age-dependent expression of pluripotent markers in uterine tissue. Beside, the different expression of pluripotent cells in each horn of uterus suggests the influence of ovarian hormones on these characteristics. The highest mRNA and protein expression for pluripotent markers was observed in stromal cells among uterine cells, which indicates this population of cells as the main site of pluripotent cells in the cow uterus.


2004 ◽  
Vol 82 (6) ◽  
pp. 363-371 ◽  
Author(s):  
R M Narayansingh ◽  
M Senchyna ◽  
M M Vijayan ◽  
J C Carlson

In this study we examined the mechanism of corpus luteum (CL) regression by measuring changes in expression of prostaglandin G/H synthase-1 (PGHS-1) and -2 (PGHS-2) in day 4 CL and inducible heat shock protein 70 (HSP-70) in day 4 and day 9 CL of immature superovulated rats. The rats were superovulated and treated with 500 µg of prostaglandin F2α (PGF2α) on day 4 or day 9 after CL formation. Ovaries and serial blood samples were removed during the 24-hour period following treatment. Plasma progesterone was determined by radioimmunoassay while mRNA abundance and protein expression were assessed by semiquantitative RT-PCR and immunoblot analysis, respectively. One hour after PGF2α, both day 4 and day 9 rats exhibited a significant decrease in progesterone secretion; however, there was a greater decrease in day 9 rats. In ovarian samples removed on day 4, there was a significant increase in mRNA for PGHS-2 at 1 hour after PGF2α. PGHS-1 mRNA content remained unchanged. Immunoblot analyses showed an increase in PGHS-2 protein expression only at 8 h. There were no changes in PGHS-1 protein expression. In day 9 rats, ovarian HSP-70 protein levels increased by 50% after PGF2α injection; however, on day 4 there was no change in expression of this protein over the sampling period. These results suggest that expression of PGHS-2 may be involved in inhibiting progesterone production and that expression of HSP-70 may be required for complete CL regression in the rat.Key words: rat, prostaglandin F2α, corpus luteum, prostaglandin G/H synthase, heat shock protein-70.


1991 ◽  
Vol 62 (2) ◽  
pp. 60-61
Author(s):  
T. L. Taljaard ◽  
S. J. Terblanche ◽  
H. J. Bertschinger ◽  
L. J. Van Vuuren

This investigation was designed to determine whether or not the technique of intrauterine insemination affects the length of the subsequent oestrous cycle. Dorper ewes (n=31) were divided into treatment and control groups. All the ewes were synchronised using 40 mg fluorogestone acetate intravaginal sponges for 14 d and 300 IU pregnant mare serum gonadotrophin on the day of sponge removal. A standard semen diluent was deposited laparoscopically in each uterine horn of ewes in the treatment, group. Teaser rams were used to detect oestrus. Progesterone profiles were used to confirm oestrus. The mean oestrous cycle length of 17,83 ± 0,69 d for the group in which the diluent was deposited by laparoscopy did not differ significantly (P0,l) from the 18,36±2,11 d of the control group. The technique of laparoscopic insemination did not influence the length of subsequent oestrous cycles.


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