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PubMed2004

Clinical and pathogenetic characteristics of pregnancy rhinitis.

Pregnancy rhinitis is a very common condition. Defined as "nasal congestion present during the last 6 or more weeks of pregnancy without other signs of respiratory tract infection, and with no known allergic cause, disappearing completely within 2 wk after delivery," it strikes one in five pregnant women, and it starts in almost any gestational week. The pathogenesis is not clear, but placental growth hormone is suggested to be involved. Smoking and sensitization to house dust mites are probable risk factors. It is often difficult to make a differential diagnosis from sinusitis, which may in pregnancy present with nasal congestion as the only symptom. Antral irrigation is diagnostic for purulent sinusitis and often needs to be repeated, as it should be treated intensively. Because of changes in pharmacokinetics, increased dosage of betalactam antibiotics is needed during pregnancy. As pregnancy rhinitis reduces quality of life and possibly also affects the fetus, there is often need for treatment. Nasal corticosteroid shave not been shown to be effective. Systemic administration should be avoided,but nasal corticosteroids could be used in pregnancy when indicated for other sorts of rhinitis. Nasal decongestants give good temporary relief, so pregnancy rhinitics tend to overuse them, giving an additional rhinitis medicamentosa. Therefore, use of nasal decongestants should be restricted to a few days. Invasive methods of turbinate reduction may be effective but are not recommendable in this self-limiting condition because of side effects. Nasal saline washings, exercise, and mechanical alar dilators are safe general means to relieve nasal congestion, but the ultimate treatment remains to be found.

Estrogens↗
PubMed1978

Effect of polypeptide hormones on stimulation of casein secretion by mouse mammary epithelial cells grown on floating collagen gels.

The in vitro effects of protein hormones on the stimulation of casein secretion by mouse mammary epithelial cells were studied. Mouse mammary glands were enzymatically dissociated and used immediately or were stored frozen and thawed just before use. Cells were cultured on floating collagen gels in the presence of insulin, cortisol and a pituitary or placental polypeptide hormone. Casein, released into the medium, was assayed by a radioimmunoassay against one of the components of mouse casein. Mammary cells released casein into the medium in the presence of as little as 10 ng of ovine prolactin per ml of medium. Human growth hormone stimulated the casein secretion to the same extent as prolactin. Human placental lactogen, ovine and bovine growth hormones were less stimulatory. Luteinizing hormone, follicle-stimulating hormone and thyroid-stimulating hormone had no effect on the stimulation of casein secretion.

Animals↗
PubMed1993

Isolation and characterization of phosphorylated bovine prolactin.

Quantitative isolation of bovine prolactin was accomplished by immunoaffinity chromatography using clonal antibody as the stationary ligand. The phosphorylated and non-phosphorylated (native) prolactins contained in the immunopurified preparations were separated by chromatofocusing. Isolates from individual pituitaries revealed that phosphorylated prolactin represented between 20 and 80% of the total prolactin. The stoichiometry of phosphate in phosphorylated prolactin was 1.4:1 when determined by amino acid analysis after preparation of the S-ethylcysteine derivative. One major phosphorylation site, serine-90, and two minor sites, serine-26 and -34, were determined by mapping and sequencing studies. Serine-90 was conserved in prolactins, growth hormones and placental lactogens. Serine-26 and -34 were conserved in prolactins, but were not found in growth hormones or placental lactogens. Absorption spectroscopy of the aromatic amino acid residues indicated that phosphorylation of prolactin was associated with a unique structural conformation.

Amino Acid Sequence↗
PubMedDate not supplied

Human placental gonadotrophin-releasing hormone (GnRH) binding sites: II. Comparison of binding and inactivation of 125I-labelled GnRH agonist to subcellular fractions following density gradient centrifugation.

Human placental homogenates and membrane fractions were centrifuged on continuous sucrose density gradients, with or without buoyant density perturbation of plasma-membranes by digitonin, and aliquots of each gradient fraction were assayed for a range of plasma-membrane and intracellular organelle markers, and for specific binding and inactivation of radiolabelled GnRH agonist (GnRHA), Buserelin ([D-Ser(tBu)6] GnRH 1-9 ethylamide). GnRH agonist (GnRHA) binding equilibrated in the same regions of control gradients as the plasma-membrane markers, EGF-receptor and alkaline phosphatase. Moreover, binding of 125I-labelled GnRHA and 125I-labelled chicken GnRH II (ch GnRH II) was enriched in the same regions of the gradients, indicating that both bound to the same membrane fractions. Digitonin pretreatment increased the buoyant density of all three placental plasma-membrane markers to a similar degree. Intracellular organelle markers (and hCG content) equilibrated in different regions of the gradient to placental surface-membranes, and were not perturbed appreciably by digitonin. In contrast, inactivation of 125I-labelled GnRHA was associated largely with the soluble (cytosol) fraction which failed to enter the gradient, and little tracer inactivation was observed in fractions enriched in GnRHA binding activity. Similar results were obtained with fractionated rat pituitary membranes. We conclude that: (a) placental GnRH binding sites do not represent binding of radiolabelled ligand to GnRH-degrading enzymes, (b) degradation of radiolabelled ligand is associated largely with placental cytosol fractions, and (c) GnRH binding activity appears to be associated largely with placental plasma-membranes.

Animals↗
PubMed1983

Differential effects of ornithine on placental lactogen and growth hormone secretion in the pregnant ewe and fetus.

The intravenous infusion of ornithine (0.5-0.9 g/kg) into five fetal sheep of 116-141 days gestation caused no significant change in concentrations of fetal plasma placental lactogen (PL) or GH as determined by specific homologous radioimmunoassays. In contrast, the intravenous infusion of ornithine (0.3-0.5 g/kg) into three of the ewes caused a 144.5 +/- 74.7 (S.E.M.)% increase in maternal plasma PL concentrations and a 255.2 +/- 55.0% increase in maternal GH concentrations. Fetal PL concentrations remained unchanged depsite the large increase in maternal PL concentrations. This study, which indicates a differential effect of ornithine on PL and GH secretion in the mother and fetus, suggests that the factors regulating PL and GH secretion in the mother and fetus are distinct.

Animals↗
PubMedDate not supplied

Maternal plasma, human placental lactogen, alpha-fetoprotein, prolactin and growth hormone in early pregnancy.

Human placental lactogen (HPL), alpha-fetoprotein, prolactin and growth hormones were assayed simultaneously twice weekly in 21 women from 4--16 weeks' gestation. Mean levels were established from 15 of the women for comparison with one woman with a twin pregnancy, two who aborted and three who received progestogen supplements. There was wide interpatient variation in all hormone levels excepting HPL. The mean levels of all except growth hormone showed an upward trend. Mean growth hormone levels were higher initially but remained within a 2--4 ng/ml range throughout. In the twin pregnancy, only HPL and alpha-fetoprotein levels were significantly raised. HPL was detected in one of the two women who aborted, whereas growth hormone was initially extremely high, falling precipitously prior to abortion in both women. Treatment with progestogen supplements did not appear to influence any of the hormones measured. This study suggests that serial estimations of HPL appear to be the most cost-effective guide to early fetal well-being of the four hormones measured.

Abortion, Spontaneous↗
PubMed2004

Large variability of trophoblast gene expression within and between human normal term placentae.

Human placenta extracts are widely used in clinical and fundamental research, particularly to study the hormonal and exchange functions of the placenta. However, very little is known about the distribution of the main hormone mRNAs in the placenta as a whole. Total placenta extracts are heterogeneous in their cellular components, as they contain material of both fetal and maternal origin, and in their structure. Results vary greatly depending upon the location of the biopsy and the number of biopsies performed. We used real-time quantitative RT-PCR to determine whether transcripts corresponding to the main hormones secreted by the human placenta (e.g. hCG, HPL and PGH) are equally distributed within and between term placentae. We also measured cytokeratin 7 transcripts, which are specifically expressed in the trophoblast, and transcripts corresponding to nuclear receptors PPARgamma and RXRalpha. A comparison of the results obtained with 12 different samples from each of four normal term placentae revealed that the amounts of transcripts differ considerably within and between each placenta. This emphasizes the need to study large numbers of samples when looking for significant differences in gene expression.

Analysis of Variance↗
PubMed1987

Effects of human placental lactogen and growth hormone on the production of insulin and somatomedin C/insulin-like growth factor I by human fetal pancreas in tissue culture.

We have investigated the ability of glucose, human GH and human placental lactogen (hPL) to alter the content and release of somatomedin C/insulin-like growth factor I (SM-C/IGF-I), and the biosynthesis, content and release of insulin from cultured human fetal pancreas. Fetal pancreatic explants obtained from glands following prostaglandin-induced abortion between 12 and 21 weeks of gestation were maintained in free-floating culture for 3-5 days before the experiments. The explants were then cultured for 3 days in medium containing either 2.7 or 16.7 mmol glucose/l with or without GH (4.5 or 45.5 nmol/l) or hPL (4.6 or 46.5 nmol/l). Serum-free medium from the final 24 h of culture was collected and SM-C/IGF-I and insulin were measured radioimmunologically in both conditioned medium and tissue explants extracted with acid ethanol. Insulin biosynthesis, determined by immunoprecipitation of [3H]leucine incorporated into insulin, was not significantly altered by any experimental variable. Incubation in the presence of 16.7 mmol glucose/l caused an increase of insulin release from explants, but had no consistent action on insulin content, compared with medium containing 2.7 mmol glucose/l. The pancreatic content and release of SM-C/IGF-I were independent of these glucose concentrations. Neither GH nor hPL altered insulin or SM-C/IGF-I content or release in the presence of the lower glucose concentration. At the higher glucose concentration, 45.5 nmol GH/l did not alter insulin release but caused a significant increase in SM-C/IGF-I content.(ABSTRACT TRUNCATED AT 250 WORDS)

Culture Techniques↗
PubMed1988

Effect of pyrimidine deoxynucleosides and sodium butyrate on expression of the glycoprotein hormone alpha-subunit and placental alkaline phosphatase in HeLa cells.

Production of the glycoprotein hormone common alpha-subunit and placental alkaline phosphatase activity can be modulated in HeLa cells by a variety of deoxynucleosides. Dose response curves for thymidine (Thd), fluorodeoxyuridine (FdUrd), bromodeoxyuridine (BrdUrd) and iododeoxyuridine (IdUrd) demonstrate that, in general, alkaline phosphatase was increased by lower concentrations of inducer than was alpha-subunit. The deoxynucleosides were not as effective as sodium butyrate as inducers of either protein. Whereas Thd and the halogenated dUrd derivatives enhanced protein expression, deoxycytidine (dCyd) had negative effects. Induction by deoxynucleosides of both alkaline phosphatase and alpha-subunit was inhibited by dCyd, but induction of alkaline phosphatase by butyrate was more sensitive to dCyd inhibition than was the butyrate-mediated induction of alpha-subunit. These results suggest that the two proteins are not regulated in a coordinate manner. Reversal of alkaline phosphatase induction by dCyd was not observed in cells preincubated with sodium butyrate for 6-24 h before the addition of dCyd, indicating that the deoxynucleoside interferes with an early event in the butyrate-mediated response. Combinations of butyrate with Thd, BrdUrd or IdUrd were synergistic with respect to the induction of HeLa-alpha. It is concluded that incorporation of the deoxynucleosides into DNA may not be required for the synergistic response since 2',5'-dideoxythymidine was an effective as Thd. Cytoplasmic dot hybridizations demonstrate that a primary effect of the various effectors is to increase the steady-state levels of alpha-subunit mRNA. There was a good correlation between alpha-subunit accumulation and corresponding levels of alpha-mRNA, suggesting that regulation occurs at a pretranslational site. Although the mechanism(s) is not understood, these data provide evidence that nucleosides or their derivatives can significantly affect gene expression.

Alkaline Phosphatase↗
PubMed1976

[The determination of human placental lactogen (HPL) for hormonal supervision in late pregnancy].

In the serum of 145 women between the 34th and 42nd weeks of pregnancy, 209 radioimmunological determinations of human placental lactogen were made, using the Pharmacia, Uppsala, Sweden, HCS Phadebas Test. Following the determination of normal HPL levels in late pregnancy, the HPL values of high-risk pregnancies were investigated in relation to normal values and compared with the clinical pattern. A satisfactory relation was found between low HPL levels and fetal growth retardation. To some extent the HPL data can also be used in monitoring severe EPH-gestosis and postmaturity. Light cases of gestosis and pregnancies involving Rh-incompatibility do not affect HPL production. The clinical findings regarding HPL levels should not be overestimated in attempting to diagnose placental insufficiency.

Erythroblastosis, Fetal↗
PubMedDate not supplied

Gonadotropin-releasing hormone and chorionic gonadotropin gene expression in human placental development.

Control of human chorionic gonadotropin (hCG) synthesis during pregnancy is poorly understood, although in vitro data suggest a role for placental gonadotropin releasing hormone (GnRH) in its regulation. To study GnRH regulation during placental development, placental tissue of different gestational ages was analyzed for GnRH and beta hCG mRNA content. cRNA probes to exonic/intronic sequences of GnRH and beta hCG transcripts were constructed and used to perform solution hybridization/nuclease protection and in situ hybridization assays. The levels of GnRH mRNA were approximately 0.1-1% of that of beta hCG mRNA, in agreement with its suggested paracrine, rather than endocrine, role. While beta hCG mRNA content decreased significantly from first trimester to term (643 to 21.6 pg/microgram RNA), there was no significant change in GnRH mRNA (0.179 to 0.155 pg/microgram RNA). While beta hCG mRNA was localized almost exclusively in syncytiotrophoblasts, GnRH mRNA was present in all cell types of the placenta, including the stroma. In the course of performing sense-strand controls in the in situ hybridization, we noted that the placenta appeared to express more antisense GnRH than sense GnRH mRNA, again, in all cell types. Solution hybridization/nuclease protection analysis with exon 1 and exon 3 probes confirmed this observation, showing that there is two to three times more antisense GnRH RNA than sense GnRH mRNA. These studies suggest that GnRH gene expression and its role in regulating hCG production in human placenta is complex and does not fit a simple model for paracrine regulation of hCG.

Chorionic Gonadotropin↗