Arachidonate metabolism in human placenta, fetal membranes, decidua and myometrium: lipoxygenase and cytochrome P450 metabolites as main products in HPLC profiles.

Eicosanoids play a key role in pregnancy maintenance and parturition. We investigated the metabolism of arachidonic acid (AA) in short-term tissue cultures of placenta, fetal membranes, decidua and myometrium. Tissues were obtained from caesarean sections before the onset of labour after uncomplicated pregnancies. The released metabolites were analysed by high performance liquid chromatography (HPLC) and specific immunoassays. In radiotracer experiments tissues were labelled with [3H]-AA and metabolites released after incubation with calcium ionophore A23187 were profiled by HPLC. Decidua was more active in metabolizing AA (turnover 34 per cent) than myometrium (28 per cent), placenta (21 per cent) and fetal membranes (17 per cent). Main product in placenta, decidua and myometrium was 12-hydroxyeicosatetraeinoic (12-HETE) (decidua: 19 per cent of released radioactivity, myometrium 14 per cent, placenta 7 per cent). Fetal membranes formed 5-HETE as main product. Another major metabolite in placenta, fetal membranes and decidua was characterized by HPLC as 5(6)-epoxyeicosatrienoic acid. Only myometrium released appreciable amounts of prostaglandins in form of 6-keto-prostaglandin F1 alpha. In non-radioactive experiments formation of eicosanoids from endogenous AA was investigated by HPLC (fluorescence- and UV-detection) and immunoassays. These experiments confirmed the high production of 12-HETE and the low formation of prostaglandins. Our results suggest that the biological role of AA-metabolites, other than prostaglandins, have as yet been underestimated.

[Pregnancy by micromanipulation in a case of excretory azoospermia associated with a natural spermatocele]. / Grossesse obtenue par micromanipulation dans un cas d'azoospermie excrétoire associée à la présence d'une spermatocèle naturelle.

Microinjection of capacitated sperm into the perivitelline space of oocytes has been performed in a case of male infertility attributed to excretory azoospermia. In this particular case, a spermatocele detected five years ago was observed, which provide motile spermatozoa. These sperm collected by direct puncture into the cyst, were capacitated using discontinuous Percoll gradient. After ovarian stimulation, seventeen oocytes were collected. Nine of them were used for classical IVF whereas the other eight were submitted to microinjection. Only one oocyte of the second group fertilized and cleaved 48 hours later. A clinical pregnancy was achieved after embryo transfer and a normal, healthy boy delivered at term.

[Intraperitoneal insemination. A new method of treatment of various types of sterility. Technic and results]. / Insémination intrapéritonéale. Une nouvelle méthode de traitement de certaines stérilités. Technique et résultats.

The results of direct intraperitoneal insemination (DIPI) with treated sperm after ovarian stimulation have been reported in this study. 21 pregnancies have been obtained during 171 cycles in 105 patients. DIPI was used for couples with long standing primary infertility not improved with classics treatments.

Alterations of intrauterine eicosanoid production in pregnancy-induced hypertension: decreased production of 12-hydroxyeicosatetraenoic acid in the placenta.

The important role of eicosanoids in pregnancy-induced hypertension is generally accepted. Because of the lack of innervation of the uteroplacental vessels, humoral vasoactive factors are important for the regulation of vascular tone. Until now, mainly the balance of vasodilatative and vasoconstrictive prostaglandins has been studied. We were able to confirm their intrauterine imbalance in hypertensive pregnancies. In addition, the placental production of less known lipoxygenase metabolites has been analyzed in this study. Intrauterine tissues (30-100mg wet weight) were examined for their release of eicosanoids. Short term tissue cultures were performed in Hanks balanced salts solution (HBSS) at 37 degrees C in an atmosphere of 95% air/5% CO2 with and without incorporation of tritiated arachidonic acid. The arachidonate metabolites in culture media were analyzed by High Performance Liquid Chromatography (HPLC) with radioactivity detection or by enzyme immunoassays or radioimmunoassays, respectively. All intrauterine tissues released more lipoxygenase metabolites than cyclooxygenase metabolites with 12-hydroxy-eicosatetraenic acid (12-HETE) as their main metabolite. The placental release of 12-HETE was significantly decreased in hypertensive pregnancies. In hypertensive pregnancies the ratio TXB2/6-keto-PGF1 alpha synthesis was increased. Lipoxygenase metabolites, especially 12-HETE, seem to have important physiological and pathophysiological functions in the intrauterine compartment. Their biological role in this context needs further investigation.

Cytochrome P450 metabolites of arachidonic acid in human placenta.

Little is known about the epoxygenase pathway of the arachidonic acid cascade in uterine tissues. In this paper, we describe the formation of epoxyeicosatrienoic acids (EETs) and dihydroxyeicosatrienoic acids (DHETs) in human term placenta after uncomplicated pregnancies. Metabolism of [3H]-arachidonic acid was analyzed in short term tissue cultures of placenta by reverse phase HPLC. Major metabolites coeluted with authentic EETs and DHETs. The formation of EETs was inhibited by carbon monoxide. In non-radioactive incubations with biopsies from seven different placentas, sufficient material for GC/MS analysis was obtained. The combined media were purified by solid phase extraction and reverse phase HPLC. The fraction coeluting with DHETs was derivatized with pentafluorobenzylbromide (PFB) and bis-(trimethylsilyl)-trifluoroacetylacetamide (BSTFA) and analyzed by GC/NICI/MS/MS. 11, 12-DHET and 14, 15-DHET were identified by their mass spectra displaying specific fragments at m/z 149 and m/z 189, respectively. Our results suggest that the epoxygenase pathway is active in human term placenta.

Predictive value of transvaginal uterine Doppler assessment in an in vitro fertilization program.

This study evaluates the prognostic value of uterine Doppler performed on the day of embryo transfer in an in vitro fertilization program. Patients were divided into two groups according to the type of ovarian stimulation. The Doppler investigation was carried out using vaginal sonography. The pulsatility index was used to evaluate the uterine blood flow pattern. The hormonal profile (estradiol, luteinizing hormone (LH) and progesterone) was correlated to Doppler results and to the pregnancy rate. The comparison between patients treated with analogs and those who were not shows a significant difference in their hormonal profile. In the first group, we found a higher estradiol and progesterone serum concentration. The LH level and the pulsatility index were statistically lower. The endometrium was thicker in patients treated with gonadotropin releasing hormone agonists. In the group of patients treated with analogs, the statistical analysis showed no significant difference in the mean pulsatility index value in women who achieved a pregnancy and in those who failed. In the group of patients who received no agonists, only one variable was significantly different: the mean age was lower in women who became pregnant. We observed no ongoing pregnancy in women who had a pulsatility index value higher than two standard deviations (pulsatility index = 3.55). We therefore suggest the use of this value as a threshold. Thus, if a patient has a high uterine artery impedance, cryopreservation should be used and embryo transfer should be postponed to a subsequent cycle, or embryo transfer delayed for a few days using co-culture. This study clearly shows the impact of hormonal response on the Doppler value and on the pregnancy rate. However, the use of a threshold value for uterine artery pulsatility index might have a clinical impact in the future management of patients attending an in vitro fertilization program.

How to deal with a rare entity: the coexistence of a complete mole and a healthy egg in a twin pregnancy?

The association of a normal and a molar egg within a twin pregnancy is extremely rare. The key to diagnosis is the fetal karyotype, thus allowing elimination of its principal differential diagnosis: partial triploid mole. We report a case where the evolution of the pregnancy was complicated by severe toxemia. Interruption of pregnancy was then necessary, even though a conservative attitude had first been considered. Throughout this case, we discuss the means of diagnosis and the clinical handling of this rare entity.