[Pregnancies following kidney transplantation and in immunosuppression with cyclosporin A]

From 1984 to 1987, offspring from six renal transplant-patients were delivered in the Department of Obstetrics and Gynaecology of the Medical School of Hannover. The patients received cyclosporine and cortisone as an immunosuppressive therapy during the pregnancies. All pregnancies ended with live births; in two cases, a caesarean section was performed. Serious congenital malformations of the newborns were not observed, only two newborns being small. In the blood of the newborns, the cyclosporine concentrations were between 85 and 65% of the maternal blood levels. In two patients, the kidney functions deteriorated significantly during and after pregnancy. An increase in blood pressure or a hypertonic crisis, however, did not occur.

Effect of ethanol on human placental transport of model amino acids and glucose

Prior studies in rodents, sheep, and subhuman primates have shown that ethanol, especially after chronic exposure, inhibits the transport of amino acids by the placenta. A small decrease in glucose transport by rat placenta chronically exposed to ethanol has also been noted. With human placental slices, however, only pharmacological (high) concentrations of ethanol impaired uptake of amino acids, and there are no data on glucose transport. In the present study, the effect of brief exposure to ethanol on human placental transport of model amino acids and glucose was studied by two techniques not previously jointly employed for this--the perfused human placental cotyledon and human placental vesicle systems. The nonmetabolizable amino acids, alpha-aminoisobutyric (AIB) acid and cycloleucine (CLEU), as well as D-glucose, and nonmetabolized glucose (3-O-methyl-D-glucose), were used as probes. AIB and CLEU are transferred normally by active transport and D-glucose by facilitated transport from maternal to fetal compartments. The perfused placental system was exposed to ethanol (300-500 mg%) for 2-4 hr and the vesicles to 200-400 mg% ethanol for times varying from 10 min to 48 hr. There was no impairment of AIB, D-glucose, or 3-O-methyl-D-glucose transfer by ethanol using these techniques. Normally, about 60% of AIB transport by human placenta is sodium dependent. This component (using the vesicle system) was also not impaired by ethanol. Ethanol caused a very small decrease of CLEU clearance by the perfused human placenta (p = 0.05) but not using vesicles.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell cycle alterations and cell death in cyclophosphamide teratogenesis

Litters of pregnant mice treated with cyclophosphamide (CP) exhibit malformations of the limbs ranging from oligodactyly to amelia. Previous studies have indicated that cell death occurs in limb buds shortly after maternal exposure. We have investigated the relationship of cell death, cell cycle perturbation, and embryo/fetal toxicity in the mouse using vital staining and flow cytometry (FCM). CP (20, 30, and 40 mg/kg) was investigated via intraperitoneal administration to Swiss-Webster mice on day 10 of gestation. At 4, 8, or 28 hours later, embryos were removed. Cell death was identified with Nile blue sulphate (NBS). Two embryos per litter were stained with NBS, and the remaining embryos were frozen at -70 degrees C prior to FCM analysis. After thawing, the forelimb buds were removed for the isolation of nuclei. Tissues were dissociated through a wire mesh followed by cytolysis with 0.1% nonidet P-40 in PBS with 0.5 mg/ml RNase. Nuclei were stained with the fluorescent nucleic acid probe propidium iodide and analyzed (10,000 nuclei per sample) for propidium iodide fluorescence by FCM. NBS revealed a dose-related increase in cell death by 8 hours after dosing. CP-induced cell death was greatest in areas of rapid cell proliferation (DNA synthesis). FCM analysis revealed retardation of progression through the S-phase of the cell cycle by 4 hours post-exposure at all doses. This retardation occurred earlier in S-phase with increasing dose and persisted through 8 hours. At 28 hours, cell cycle histograms were normal in the low-dose embryos, but remained perturbed in the intermediate- and high-dose embryos. On day 17 of gestation, the last group of dams was killed. A high incidence of fetal malformations, including limb defects, occurred at the 20 mg/kg dose, and fetal mortality was observed at 30 and 40 mg/kg. The pattern and magnitude of cell death correlated with cell cycle perturbation and fetal toxicity at term, suggesting a relationship between cell cycle perturbation, cell death, and malformations produced by CP.

Effect of vaginal douching with povidone-iodine during early pregnancy on the iodine supply to mother and fetus

Vaginal douching with polyvinylpyrrolidone iodine (PVP-I) during pregnancy results in maternal iodine overload and increases the iodine content of amniotic fluid. We evaluated the possible effects of this therapy on the thyroid of the fetus by investigating 62 women with a mean duration of amenorrhea of 20 weeks who solicited controlled abortion. Nineteen of them douched daily with PVP-I for 7 consecutive days before abortion (treated group). The other 43 women were not treated (control group). In both groups the iodine content was determined in the fetal thyroid and in amniotic fluid and maternal urine at the time of abortion. In addition, in the treated group the concentrations of iodine were also determined in amniotic fluid and urine before therapy and in urine after 4 days of therapy. There were no differences in the concentrations of iodine in urine and amniotic fluid in the control group and in the treated group before therapy. In the treated group urinary iodine increased from 6.1 +/- (SEM) 0.8 micrograms/dl before therapy to 91 +/- 20 micrograms/dl after 4 days and to 153 +/- 60 micrograms/dl after 7 days of therapy (p less than 0.001). In parallel, iodine in amniotic fluid increased from 1.2 +/- 0.2 micrograms/dl before therapy to 3.7 +/- 1.3 micrograms/dl after 7 days (p less than 0.05). In both groups the iodine content of the fetal thyroid increased with gestational age. However, it increased more rapidly in the treated group (from 1 to 7.7 micrograms) than in the control group (from 1 to 2.5 micrograms), p less than 0.05.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiovascular responses to forskolin in the ovine fetus

Six near-term ewes were instrumented to measure regional blood flows in the maternal and fetal subthoracic structures and allowed to recover for 5 days. Control blood flows were measured and 10(-3) molar forskolin was infused in the fetal hindlimb vein at 1 ml/min. After 10 min of infusion, maternal and fetal regional blood flows were measured. The fetal blood pressure was 44 +/- 3 mmHg in the control state and 40 +/- 4 mmHg after forskolin, P less than 0.056. The fetal renal vascular resistance changed from 24.4 +/- 2.4 to 17.5 +/- 1.7 mmHg.ml-1.min.g, P less than 0.005. The placenta had a control resistance of 27.7 +/- 5.0 and 25.6 +/- 5.1 mmHg.ml-1.min.g after forskolin, P less than 0.05. The placental membranes showed vasodilation: control resistance was 261 +/- 49 and 168 +/- 39 mmHg.ml-1.min.g after forskolin, P less than 0.02. The generalized vasodilation of the fetal circulation was paralleled in the maternal circulation. Forskolin, a lipid soluble diterpene, apparently had a placental clearance close to the theoretical maximum. Vasodilation was seen in the maternal renal, placental and uterine vasculatures. Maternal blood pressure was unchanged. Maternal placental vascular resistance was 47.4 +/- 3.0 mmHg.ml-1.min.g in the control state and 40.6 +/- 3.3 mmHg.ml-1.min.g after forskolin, P less than 0.02. Forskolin is a vasodilator in both the fetal and maternal circulations. The maintenance of a relatively normal blood pressure in the face of regional vasodilation shows that forskolin may have a positive inotropic effect on the fetal heart. These results indicate that neither the fetal nor the maternal ovine placental vasculature is maximally dilated in the control state.

Relationship of embryotoxicity to genotoxicity of lead nitrate in mice

Frequency of sister chromatid exchanges (SCEs), nucleolar organizing regions (NORs) and chromosomal aberrations were analysed, in maternal bone marrow and fetal liver and/or lung cells of ICR Swiss Webster mice, following maternal exposure to lead nitrate on gestational day 9. The number of implantations and morphological changes in day 18 fetuses, following the treatment, were also noted. Chemical analysis of lead in maternal and fetal tissues showed that it is readily transferred across the placenta. Lead caused a moderate, but statistically significant, increase in the frequency of SCEs in maternal bone marrow cells and significant reduction in NORs at the 2 highest dose levels (150 and 200 mg/kg b.w.). Lead treated animals showed several specific chromosomal aberrations, mostly deletions in maternal bone marrow and fetal cells. Aneuploidy was found to be frequently associated with the lowest dose levels of lead nitrate (100 mg/kg). Maternal treatment with lead nitrate also significantly increased embryonic resorptions and reduced placental weights. The results suggest that the embryotoxic effects of lead might be associated with the chromosomal changes.

Histological changes in the placenta induced by maternal alcohol consumption in the rat

To investigate the placental enlargement which accompanies maternal alcohol consumption during pregnancy, Sprague-Dawley rats were given 20% ethanol for 4 weeks prior to mating and 30% ethanol throughout gestation. Pair-fed controls received an isocaloric amount of corn starch and chow, with water ad libitum, and ad libitum controls received rat chow and water. On days 17, 18, 19 and 20 of gestation, placentas were removed for histological observation. On days 18-20, the placentas of alcohol-fed rats weighted significantly more than did those of controls, although there was no difference in weight on day 17. Giant cells in the basal zone were significantly increased in number and size in alcohol-fed rats compared to controls. Trophoblastic cells in the basal zone were significantly larger in the alcohol group than in the control groups except on day 17. The maternal blood channels in the labyrinth were wider and more filled with blood corpuscles in the alcohol group than in either control group. It is concluded that the increased weight of the placenta may be largely due to stagnated maternal blood cells in the labyrinthine blood channels and also to the increased number and size of giant cells and the enlarged trophoblastic cells in the basal zone.

Transplacental passage and hemodynamic effects of esmolol in the gravid ewe

Using a chronic maternal-fetal sheep preparation, the authors determined the transplacental passage and the hemodynamic changes consequent to maternal administration of esmolol. Fifteen experiments were performed in six chronically instrumented pregnant ewes near term. Each animal received esmolol iv, 500 micrograms.kg-1.min-1, for 4 min and then 300 micrograms.kg-1.min-1 for 6 min. Maternal and fetal blood esmolol concentrations (mean +/- SEM) were 1.2 +/- 0.28 and 0.1 +/- 0.03 micrograms/ml, respectively, at the completion of the infusion, and 0.03 +/- 0.01 microgram/ml in the mother and not detectable in the fetus 10 min after stopping the infusion. Despite the relatively low blood esmolol concentration in the fetus compared to the mother, the hemodynamic effects in the fetus were similar to those in the mother. The maximal decrease of maternal mean arterial pressure (MAP) and heart rate (HR) were 7 +/- 2 and 14 +/- 3% (mean +/- SEM), respectively (P less than .05). The maximal decrease of fetal MAP and HR were 7 +/- 2 and 12 +/- 3%, respectively (P less than .05). No changes were seen in maternal or fetal acid-base variables, and intra-amniotic pressure was not affected. The authors conclude that esmolol has a rapid but relatively small transplacental passage, and it is eliminated rapidly from both maternal and fetal plasma.

Perinatal growth retardation caused by triethyl lead chloride treatment of mice during late gestation

Female mice were injected intraperitoneally daily from day 18 of gestation and throughout lactation with triethyl lead chloride (TEL; 0.0, 0.5 and 1.0 mg/kg body wt). Off-spring of treated mothers displayed a slight perinatal growth retardation. Male off-spring appeared to be more sensitive to TEL, as indicated by their lower body weights. During the latter half of the lactation period the treated sucklings grew faster than controls, thereby compensating for their initially retarded growth, by the time of weaning. The hepatic cytochrome P-450 content of 9 to 10-day old sucklings of treated mothers was lower than in corresponding controls. We suggest that perinatal growth retardation is initiated by a disturbance in the uterus, e.g. reduced nutrient transport across the placenta.

[Regulation of the fetoplacental unit. 3. Suppression of the fetoplacental unit by cortisol in relation to the maturity of the fetus]

The present study investigates the suppression of free plasma oestriol by cortisol in mature and immature foetuses. 6 patients in the 32nd week of gestation and 6 patients in the 38th week received an infusion of 100 mg cortisol (Hydrocortison Hoechst) from 10 a.m. to 12 a.m. Blood specimens (5 ml) were drawn from 8 a.m. to 5 p.m. in 60 or 30 minutes intervals, respectively. Free plasma oestriol was measured by radioimmunoassay, total plasma cortisol by the protein binding method. In the 32nd week of gestation plasma oestriol rose from 501 +/- 240 ng/ml to 1035 +/- 301 ng/ml, whereas oestriol decreased from 5.2 +/- 1.0 ng/ml to 3.9 +/- 1.5 ng/ml (p less than 0.001). After an analogous rise of cortisol, oestriol levels in the 38th week were suppressed from 12.5 +/- 3.3 ng/ml to 4.0 +/- 1.6 ng/ml (p less than 0.001). The degree of oestriol suppression of 68 percent in the 38th week markedly exceeded that of the 32nd week (25%). According to these results, the hypothalamic-hypophyseal system of mature foetuses exhibits a higher sensitivity to the feed back action of cortisol than immature foetuses.

Fluid transport across human fetal membranes affected by human amniotic fluid prolactin: an in vitro study

The aim of the study was to investigate the effects of human amniotic fluid (AF) prolactin (PRL) on the transfer of fluids across human fetal membranes, detected in vitro by weight change. We have developed a system, consisting of an inner compartment (4 ml), suspended in an outer compartment (40 ml), and separated from it by a 2 cm2 circular piece of fresh human fetal membrane (amnion, chorion and adhering decidua). The weight of the inner compartment was continuously registered with an electronic precision balance. Osmolality changes or hydrostatic pressure differences did not affect the rate of mass transfer through the membranes. Potassium cyanide significantly influenced the mass transfer in favour of the applied hydrostatic pressure difference (+2 cm H2O to the amniotic side) or osmotic pressure difference (amniotic side 265 mosm/kg/decidual side 285 mosm/kg). The PRL preparations used were human and ovine pituitary PRL, as well as three fractions isolated from human AF by fractionated ammonium sulphate and ethanol precipitations, followed by Sephacryl chromatography. All PRL preparations were tested in physiologic concentrations (0.5 to 5 micrograms/ml). Only the two largest AF-PRL variants significantly disturbed the balance of fluid transfer across the membranes when added to the fetal (amniotic) side of the membrane. This resulted in a net increase in fetomaternal transfer of 120 to 180 microliters. This effect could be repeated and lasted for at least 25 minutes. Using an antibody against hPRL the effect was completely blocked. Neither AF-PRL added to the maternal (decidual) side of the membrane nor oPRL or human pituitary PRL added to the amniotic or decidual side changed the rate of mass transfer across the membranes.

[Medicamentous obstetric analgesia with pentazocine in comparison with an untreated control group]

In order to establish whether a powerful analgesic such as pentazocine administered during birth may damage the child or have negative influence on the course of birth, the course of delivery was studied in 40 patients, 20 of whom were given a single dose of 30 mg pentazocine administered intramuscularly. There were no differences in duration of birth, CTG, blood gases post partum, or Apgar scores as compared to the untreated control group. As regards the pharmacokinetics, the serum pentazocine levels of the gravidae corresponded to those found in non-pregnant subjects; the levels found in blood from umbilical cords and new-borns were at the lower limit of detectability. Almost all of the gravidae described the obstetric analgesia as good or adequate. The principal side effect, mentioned by one-third of the pentazocine group, was slight fatigue. As regards the newborns, the fetal outcome in the two groups was the same.

Placental transfer of beta-adrenergic antagonists studied in an in vitro perfusion system of human placental tissue

Maternofetal transfer of five beta-blockers differing in molecular weight, solubility, and binding to albumin was studied using a dual in vitro perfusion system of an isolated cotyledon of human placenta. At steady state the diffusion rate of the lipid-soluble propranolol, timolol, and labetalol was three to four times higher than that of the hydrophilic atenolol and celiprolol. Albumin binding had no significant effect on diffusion when equal concentrations were used in the two perfusion circuits. With increased albumin concentration on the fetal side an acceleration of the diffusion of propranolol could be shown. Propranolol and labetalol showed considerable binding to placental tissue. After bolus injection transfer was clearly suppressed, as a result of tissue binding, and there was a delay until a steady state of diffusion was reached when constant concentrations were maintained in the maternal compartment. With recirculation of the fetal and maternal compartments propranolol rapidly equilibrated in the two perfusion circuits at 35% of the initial level in the maternal circuit. Atenolol after 4 hours of recirculation had not reached full equilibration between the two compartments, and the fetal concentration was at 55% of the initial level on the maternal side.

Transplacental passage of a progesterone antagonist in monkeys

The progesterone antagonist RU 486 dramatically increases myometrial contractility of the pregnant uterus, making it a potential adjunctive therapy for labor induction or therapeutic pregnancy termination. Sixteen female cynomolgus monkeys were studied during the second or third trimester of pregnancy. Hysterotomies were performed with the animals under anesthesia, providing access to the intact placental vasculature. RU 486 (25 mg) was injected intravenously into the mothers. Serial blood samples were drawn from the maternal and fetal-placental compartments for a period of 2 hours. RU 486 achieved a gradient equilibrium between the maternal and fetal-placental circulation within 5 minutes, suggesting free passage by simple diffusion. The clearance kinetics of immunoreactive RU 486 are consistent with an open three-compartment system in mother and fetus. The fetal-placental index decreased from 31.2% to 17.8% between the second and the third trimester of pregnancy. There was no acute toxicity of the RU 486 noticed during the experimental course.

Influence of ethanol consumption on maternal-fetal transfer of zinc in pregnant rats on day 14 of pregnancy

The hypothesis that a biochemical lesion underlying the development of fetal alcohol syndrome is an ethanol-induced reduction in placental zinc transfer was tested. Placental zinc transfer was assessed in control and ethanol-fed dams on d 14-15 of pregnancy. Litters from ethanol-fed dams were characterized by a high resorption frequency and fewer live fetuses per litter than litters from control dams. In addition, fetuses from the ethanol-fed dams weighed less than control fetuses. However, despite the negative effects of ethanol intake on litter outcome, placental and fetal retention of 65Zn was similar in the two groups. Therefore, an ethanol-induced fetal zinc deficiency does not seem to have a role in the production of the gross structural malformations associated with fetal alcohol syndrome when adequate zinc is provided in the diet.

The effect of toxic doses of lanthanum and cerium on the placental barrier and the blood/organ barrier in mice after intravenous injection of these elements

In earlier studies the toxicity of the lanthanides was determined on the basis of the LD50/30 value, increase of serum ornithine carbamoyltransferase activity, and the degree of passage of the lanthanides to the fetuses and milk. The purpose of the present work was to investigate the effects of toxic doses of lanthanum and cerium on the function of the placental barrier and the blood/organ barrier in mice using substances of known molecular weight labelled with radionuclides (14C-aminoisobutyric acid--AIB, 3H-thymidine and 125I-albumin). Increased uptake of 14C-AIB and 3H-thymidine was demonstrated in the liver, spleen and placenta of mice after toxic doses of La and Ce indicating disturbances in the function of the blood/organ barrier (liver, spleen, placenta) due to damage to the vascular endothelium or cell membranes. No disturbances were shown in the function of the placental barrier (which would have caused increased passage of these markers to the fetus), and rupture of the cell membranes in the studied tissues was not demonstrated (it would have caused increased passage of 125I-albumin, a macromolecular compound) in any of the studied organs in mice.

The effect of epostane, a 3-beta hydroxy steroid dehydrogenase inhibitor, on maternal and fetal steroid levels during mid-gestation

A double-blind, placebo-controlled trial was conducted to assess the maternal and fetal endocrine effects of epostane, an inhibitor of progesterone synthesis, in mid-pregnancy. Although present in the maternal circulation, epostane was not detected in cord blood or amniotic fluid. Maternal and fetal progesterone levels fell by 80% and 95% respectively with maintenance of the fetal arterio-venous difference while oestradiol and aldosterone levels were affected to a lesser extent. The mechanism of 3-beta hydroxy steroid dehydrogenase suppression and the relation between fetal and maternal progesterone levels are discussed.

[Influence of pindolol on maternal cardiovascular parameters and contractility of the puerperal uterus]

In the present study the influence of beta-receptor blockers on uterine activity was examined. In the postpartum period of 16 enrollees blood pressure, heart frequency, contraction frequency, basal tone, contraction intensity as well as the Montevideo Units were recorded at intervals of 10 minutes during and after infusion of 0.8 resp. 1.6 mg pindolol. Pindolol with its inherent intrinsic sympathomimetic activity led to the well known decrease of blood pressure but did not increase uterine activity.