Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study determined the effects of intrauterine injections of recombinant ovine interferon-tau; (roIFN-tau; 2 x 10(7) antiviral units/day) or control proteins (6 mg/day) from day 11 to day 14 post-oestrus = day 0) on endometrial expression of receptors fro oestrogen, progesterone and oxytocin in cyclic ewes. Plasma concentrations of progesterone were greater on day 15 in ewes receiving roIFN-tau compared with control proteins (P < 0.02, treatment x day). Ewes injected with roIFN-tau had lower endometrial levels or oestrogen receptor mRNA (P > 0.10) and protein (P < 0.01) on day 15 compared with ewes receiving control proteins. In situ hybridization analysis indicated that oestrogen receptor mRNA was more abundant in the luminal and glandular epithelium of control ewes compared with roIFN-tau-treated ewes. Immunoreactive oestrogen receptor was also present in the luminal and glandular epithelium of control, but not roIFN-tau-treated ewes. Endometrial levels of progesterone receptor mRNA and protein were not different (P > 0.10) between control and roIFN-tau-treated ewes. In situ hybridization analyses indicated that progesterone receptor mRNA abundance was low in endometrial epithelium and stroma of both control and roIFN-tau-injected ewes. Immunoreactive progesterone receptors were present in the endometrial stroma and epithelium of control ewes, but confined to the stroma of roIFN-tau-treated ewes. Oxytocin receptor density was lower (P < 0.01) in the endometrium of ewes injected with roIFN-tau than control proteins; however, oxytocin receptor affinity was not affected (P > 0.10) by treatment. Concentrations of 13,14-dihydro-15-ketoprostaglandin F2a (PGFM) were not increased by exogenous oxytocin administration in control and roIFN-tau-treated ewes on days 10 or 12 post-oestrus. However, on day 14, control ewes responded to oxytocin with increased plasma concentrations of PGFM, whereas ewes receiving roIFN-tau remained unresponsive to oxytocin. These results indicate that the an tiluteolytic effects of IFN-tau are to prevent increases in endometrial oestrogen receptor MRNA and protein and oxytocin receptor density which abrogates uterine release of prostaglandin F2a during maternal recognition of pregnancy. IFN-tau may inhibit the synthesis of oestrogen receptor mRNA by a transcriptional or post-transcriptional regulatory mechanism to suppress oxytocin receptor formation during early pregnancy in ewes.
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PMID:Intrauterine injection of ovine interferon-tau alters oestrogen receptor and oxytocin receptor expression in the endometrium of cyclic ewes. 880 Jun 45

The effects of recombinant ovine interferon-tau (IFN-tau) and progesterone on oestrogen-stimulated expression of endometrial receptors for oestrogen (ER), progesterone (PR) and oxytocin (OTR) were determined in ovariectomized ewes. Cyclic ewes (n = 16) were ovariectomized and fitted with uterine catheters on Day 4 of the oestrous cycle (Day O, oestrous) and assigned randomly in 2 x 2-factorial arrangement to receive daily intrauterine injections of either recombinant ovine IFN-tau (roIFN-tau; 2 x 10(7) anti-viral units) or control proteins from Day 11 to Day 15 and 50 mg progesterone from either Day 4 to Day 10 (E-P) or Day 4 to Day 15 (E+P). All ewes received 50 micrograms oestradiol-17 beta on Days 13, 14 and 15 and were hysterectomized on Day 16. In control ewes, endometrial ER mRNA, PR protein and OTR density were greater in E-P- than E+P- treated ewes. In E-P ewes, roIFN-tau decreased oestrogen-stimulated increases in ER and OTR, but not PR expression compared with control ewes. In E+P ewes, endometrial ER mRNA and protein, PR mRNA and protein, and OTR levels were lower in roIFN-tau-treated ewes than control ewes. Immunoreactive ER and PR were absent in the endometrial luminal and superficial glandular epithelium of roIFN-tau compared with control ewes, but were present in the deep glandular epithelium and stroma regardless of steroid or protein treatment. These results indicate that progesterone affects oestrogen-induced increases in endometrial ER, PR and OTR expression in the PR+ deep glandular epithelium and stroma, whereas IFN-tau suppresses oestrogen-induced increases ER, PR and OTR expression in the PR- luminal and superficial glandular epithelium. These combined actions of IFN-tau and progesterone to suppress oestrogen-induced increases in endometrial OTR formation would prevent pulsatile production of luteolytic prostaglandin F2 alpha by the endometrium during early pregnancy.
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PMID:Effects of interferon-tau and progesterone on oestrogen-stimulated expression of receptors for oestrogen, progesterone and oxytocin in the endometrium of ovariectomized ewes. 887 43

Three groups of intact hinds (n = 10-18) and one group of ovariectomized hinds were treated with progesterone by mean, of Controlled Internal Drug Releasing (CIDR) devices for 13 days (device removal = Day 0). Group 1 served as controls; group 2 received injections of 4 mg recombinant bovine interferon-alpha,1 twice daily from Days 13 to 21; group 3 was run with a stag from Days 0 to 3, and all hinds were subsequently diagnosed pregnant; group 4 (ovariectomized) was treated with CIDR devices and estradiol to mimic steroid secretion during the estrous cycle. Progesterone profiles were determined from thrice-weekly plasma samples from Days -13 to 28. Rectal temperature was measured in a subset of groups 1 and 2 from Days 9 to 21. Oxytocin-induced prostaglandin F2 alpha release was measured in a subset of groups 1, 2, and 4 on Days 2, 4, 10, 16, and 18. Data are presented as means +/- SEM. Exogenous interferon delayed luteolysis (> or = 28 vs. 21.2 +/- 0.55 days, P < 0.0005) and induced transient pyrexia after the first injection (39.89 +/- 0.11 vs. 38.88 +/- 0.19 degrees C, p < 0.0005). Incidence of oxytocin-induced PGF2 alpha release in control hinds was greater on Days 2 and 18 than on Days 4 and 10 (8/8 and 7/8 vs. 3/8 and 0/8, respectively; p < 0.05) and was greater in control than in interferon-treated hinds on Days 16 and 18 (5/8 and 7/8 vs. 1/8 and 1/8, respectively; p < 0.05). Profiles of plasma progesterone concentration and oxytocin sensitivity in steroid-treated ovariectomized hinds did not differ from those in control hinds. These results suggest that steroid-controlled uterine oxytocin sensitivity is important in luteolysis and is suppressed by the administration of interferon, the putative embryonic pregnancy recognition signal in red deer.
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PMID:Exogenous interferon delays luteal regression in red deer hinds (Cervus elaphus) by suppressing steroid-induced endometrial oxytocin sensitivity. 887 4

Endometrial oxytocin receptors and total production of PGF by endometrial epithelial cells were measured in 10 cyclic cows after intrauterine injections of recombinant bovine interferon-tau plus BSA or BSA alone. Cows received twice daily injections (via intrauterine catheters) of 200 micrograms of recombinant bovine interferon-tau plus 1.3 mg of BSA (n = 5) or 1.5 mg of BSA (n = 5) from d 14 to 17 after estrus. On d 17, the reproductive tracts of each cow was removed at slaughter, and endometrial epithelial cells were cultured with 0, 2, or 50 ng/ml of recombinant bovine interferon-tau. After 24 h, oxytocin (2 x 10(-7) M) was added to one-half of the culture wells, and the medium was sampled at 0, 30, and 90 min for analysis of total PGF (PGF plus 13, 14-dihydro-15-keto-PGF2 alpha). In vivo treatment with recombinant bovine interferon-tau + BSA reduced total secretion of PGF in culture (1.49 +/- 0.06 vs. 2.80 +/- 0.07 ng/micrograms of DNA), but did not block the oxytocin-induced stimulation in total secretion of PGF. In vitro treatment of cells with recombinant-bovine interferon-tau did not decrease basal secretion of total PGF. Oxytocin receptor binding at d 17 was low in both treatments but slightly attenuated in the group treated with recombinant bovine interferon-tau.
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PMID:Treatment with recombinant bovine interferon-tau in utero attenuates secretion of prostaglandin F from cultured endometrial epithelial cells. 888 Apr 61

Previous studies in the endometrium of ruminants showed that type I interferon (IFN) prevents oxytocin receptor (OTR) formation. We studied the effect of IFN-alpha on human myometrial cells in culture expressing a high density of biologically active OTR. We found that IFN-alpha induced a 35-50% decrease in OTR mRNA and protein and that this inhibition was time and dose dependent. Maximal inhibition of OTR mRNA was obtained after 2-3 days, whereas 1-(beta-mercapto-beta, beta-cyclopentamethyl-enepropionic acid,2-O-Me-Tyr,Thr4,Orn8,Tyr9-amide)-[125I]vasotocin ([125I]OTA) binding reached a nadir after 3-4 days, with half-maximal inhibitory concentration (IC50) = 1,100 U/ml. Mathematical analysis of multiple homologous competition curves for [125I]OTA indicated that IFN-alpha treatment (5,000 U/ml x 3 days) reduced just the binding capacity (Bmax) without changing the binding affinity. Accordingly, the same treatment with IFN-alpha did not affect the half-maximally effective concentration (EC50) for the oxytocin-induced increase in intracellular calcium but significantly decreased maximal responsiveness (Emax) of myometrial cells to OT stimulation. In conclusion, our data demonstrate, for the first time, a negative regulation by IFN-alpha of the steady-state expression of OTR mRNA in cultured human myometrial cells obtained from nonpregnant uteri. This inhibition was followed by a parallel decrease in both the Bmax for [125I]OTA and Emax for oxytocin, suggesting a decreased OTR protein availability.
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PMID:Interferon-alpha downregulates expression of the oxytocin receptor in cultured human myometrial cells. 894 70

At the time of recognition of pregnancy, the bovine conceptus (embryo and associated membranes) must produce a signal that will prevent luteolysis otherwise induced by pulsatile release of prostaglandin (PG) F2alpha from the uterus in response to oxytocin (OT). In ruminants, trophoblastic interferon tau (IFN-tau) released by the conceptus appears to be the most likely candidate to trigger the establishment of pregnancy. We have compared the effect of recombinant (r) ovine (o) and bovine (b) IFN-tau on PG production, using a fully characterized model of cultured endometrial cells. In uterine epithelial cells, the production of PGF2alpha was stimulated 7.1-fold (p < 0.0001) and that of PGE2 89.0-fold (p < 0.0001) by rbIFN-tau, and 3.6-fold and 29-fold, respectively, by roIFN-tau. The stimulation resulted in a net increase in the PGE2:PGF2alpha ratio of 7.7 with rbIFN-tau and 5.1 with roIFN-tau at the optimal concentration of 1 microg/ml (p < 0.0001). By contrast, addition of OT (100 nM) alone resulted in a decrease of the PGE2:PGF2alpha ratio. The level of stimulation of PGE2 by IFN-tau was reduced in the presence of OT, showing that there was some interaction between OT and IFN-tau at the cellular level in the regulation of PG production. In uterine stromal cells, roIFN-tau and rbIFN-tau stimulated PGE2 and PGF2alpha production 12-fold (p < 0.0001). The ratio of PGE2:PGF2alpha was not affected in a dose-dependent manner, but was increased (p < 0.001) at a single dose of rbIFN-tau (0.001 microg/ml) and roIFN-tau (0.01 microg/ml). The results indicate that 1) bovine endometrial cells are more responsive to rbIFN-tau than to roIFN-tau, 2) rIFN-tau regulates PGs by stimulating PGE2 preferentially, and 3) rIFN-tau transforms the response to OT from stimulation of PGF2alpha to stimulation of PGE2.
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PMID:Recombinant ovine and bovine interferons tau regulate prostaglandin production and oxytocin response in cultured bovine endometrial cells. 911 39

An analysis of results of treatment of 100 patients with postinjectional abscesses (PA) has shown their tendency to continuous inflammation in (23.9 +/- 5.4)% of the cases. Under condition of long duration of PA microorganisms of Staphylococcus aureus species have been isolated which possess 2-6 times greater capacity for inactivating the natural antiinfectious resistance factors: lysozyme, complement, immunoglobulins, bacterial component of the interferon. The inclusion of oxytocin preparation into the scheme of treatment which inhibits manifestations of antilysozymal activity of staphylococci allowed the frequency of prolonged unfavourable periods of PA to be reduced to 10.9%.
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PMID:[The connection between the duration of the course of postinjection abscesses and the biological characteristics of the causative microorganisms]. 916 56

Skewing of the sex ratio at birth occurs in red deer in response to dominance status, with dominant hinds giving birth to a higher proportion of male calves than subordinates. To investigate the physiological basis for this phenomenon, reproductive tracts were collected from red deer during a cull for management purposes carried out on the Island of Rum, Scotland. Blastocysts were flushed from the uterus and sexed by polymerase chain reaction using Y chromosome-specific primers. Concentrations of interferon (measured as antiviral activity) in uterine flushings, of oxytocin receptors in endometrium, and of progesterone in jugular venous blood were measured, and ovarian morphology was recorded. Times of mating were determined retrospectively from calving dates observed during the following spring. Changes in uterine and fetal weights and sizes confirmed the degree of reproductive synchrony. Intervals between stages of blastocyst development (spherical, tubular, filamentous, and attached) derived from the observed incidence of each form showed that approximate times of blastocyst elongation and attachment were 13 and 30 days after conception, respectively. Hinds carrying male blastocysts were in better body condition (higher kidney fat weights, P = 0.025) than those carrying females. Interferon was detectable in uterine flushings from 1 of 7 hinds carrying early filamentous blastocysts and 5 of 12 hinds carrying late filamentous blastocysts, but in no case where the blastocysts were male (P = 0.035). Oxytocin receptor concentrations in caruncular endometrium (but not in intercaruncular endometrium) were lower in pregnant than in nonpregnant hinds (P < 0.05), but there was no correlation with interferon concentrations in flushings. Corpora luteal concentrations of oxytocin ranged from 1.8 to 51.2 micrograms/g tissue and declined with advancing blastocyst development. The data are consistent with the hypothesis that sexual dimorphism in trophoblast interferon production leads to differential blastocyst loss and hence to sex ratio skewing on the basis of dominance status.
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PMID:Blastocyst development and conceptus sex selection in red deer Cervus elaphus: studies of a free-living population on the Isle of Rum. 920 71

PGs are important regulators of reproductive processes. At the time ofluteolysis in vivo, PGF2alpha is produced by endometrial cells, in response to oxytocin (OT). The mechanism by which OT induces the release of PGF2alpha remains to be defined. We have used 13 different cultures of bovine epithelial endometrial cells to study the effect of OT on the regulation of PGF2alpha and to identify the possible involvement of cyclooxygenases (COXs). OT induced a dose-dependent increase of both inositol phosphates (IPs) and [Ca2+]i concentration in epithelial cells labeled with [3H]-myoinositol or loaded with fura-2 (using a fluorescent microscope imaging system), respectively. OT induced a dose-dependent increase of both PGF2alpha production and COX-2 gene expression (as demonstrated by RT-PCR and Northern blots). PGF2alpha production was increased from 13.3 +/- 2.0 to 166.8 +/- 22.5 ng/ml (P < 0.0001). On the other hand, COX-2/beta-actin mRNA gene expression (as determined by densitometric analysis) was increased 5.1 +/- 0.7-fold (P < 0.001) with OT (10[-7] M) treatment, compared with control. Addition of indomethacin (1 microM) and a specific COX-2 inhibitor (NS-398, 1 microM) blocked the OT-induced PGF2alpha production. COX-1 and phospholipase A2 mRNA were expressed at steady-state levels, but no effect of OT was detected on their regulation. Combined to OT, 10 microq/ml of recombinant ovine interferon-tau (roIFN-tau) was able to decrease significantly (P < 0.0001) the dose-dependent increase of PGF2alpha production. Furthermore, partial bovine COX-1 (777 pb) and COX-2 (449 bp) cDNAs were cloned and sequenced. An homology of 83% and 97% was found in relation with rat and sheep, for COX-1, respectively. COX-2 was found to bear 84%, 86%, and 87% of homology in relation to rat, guinea pig, and human, respectively. Collectively, these results demonstrate, for the first time, that COX-2 is involved in the mechanism by which OT regulates PGF2alpha production in the endometrium.
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PMID:Cellular mechanisms involved during oxytocin-induced prostaglandin F2alpha production in endometrial epithelial cells in vitro: role of cyclooxygenase-2. 934 8

Three experiments were carried out to investigate the secretion of luteolytic hormones in red deer hinds during the oestrous cycle, early pregnancy and after administration of interferon, the putative pregnancy recognition signal. Three groups of hinds (n = 8-9 per group) were treated with progesterone-impregnated intravaginal controlled internal drug releasing (CIDR) devices for 13 days (device withdrawal = day 0). Group 1 (n = 9) served as controls; Group 2 (n = 8) received injections of 4 mg recombinant bovine interferon-alpha 1 l twice a day on days 13-18; Group 3 (n = 9) were run with a fertile stag on days 0-3. Plasma samples collected each day on days 16-23 were analysed for progesterone. Plasma samples collected each hour for 16 h on days 4, 10, 16, 18 were analysed for oxytocin and the prostaglandin F2 alpha (PGF2 alpha) metabolite (PGFM). Plasma progesterone concentrations declined to < 1 ng ml-1 between days 18 and 25 in control hinds indicating that luteolysis had occurred, whereas there was no endocrine evidence of luteolysis in interferon-treated or pregnant hinds. Control hinds (6/9) exhibited synchronous pulses of oxytocin and PGF2 alpha secretion on day 18, a greater proportion than on any other day in these hinds or on any day in the interferon-treated or mated hinds (P < 0.05). In a second experiment, close synchrony in secretion of oxytocin and PGF2 alpha pulses was evident in an unmated hind when samples were collected every 12 min on day 18. In a third experiment, oxytocin-induced PGF2 alpha secretion was potentiated by oxytocin administration at an interval of 1 h and inhibited by administration at a 6 h interval (P < 0.05). These results suggest that synchronous pulsatile secretion of oxytocin and PGF2 alpha induces luteolysis and is suppressed by pregnancy or administration of interferon. Oxytocin-induced alterations in uterine oxytocin sensitivity may underlie the pulsatile nature of luteolytic hormone secretion in red deer.
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PMID:Effect of pregnancy and exogenous interferon on synchronous pulsatile release of oxytocin and luteolytic prostaglandin F2 alpha in red deer (Cervus elaphus). 946 99


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