Decrease In Fetal Body Weight Research Articles

Maternal GLP-1 receptor activation inhibits fetal growth.

Glucagon-like peptide 1 (GLP-1) regulates food intake, insulin production, and metabolism. Our recent study demonstrated that pancreatic α-cells-secreted (intraislet) GLP-1 effectively promotes maternal insulin secretion and metabolic adaptation during pregnancy. However, the role of circulating GLP-1 in maternal energy metabolism remains largely unknown. Our study aims to investigate systemic GLP-1 response to pregnancy and its regulatory effect on fetal growth. Using C57BL/6 mice, we observed a gradual decline in maternal blood GLP-1 concentrations. Subsequent administration of the GLP-1 receptor agonist semaglutide (Sem) to dams in late pregnancy revealed a modest decrease in maternal food intake during initial treatment. At the same time, no significant alterations were observed in maternal body weight or fat mass. Notably, Sem-treated dams exhibited a significant decrease in fetal body weight, which persisted even following the restoration of maternal blood glucose levels. Despite no observable change in placental weight, a marked reduction in the placenta labyrinth area from Sem-treated dams was evident. Our investigation further demonstrated a substantial decrease in the expression levels of various pivotal nutrient transporters within the placenta, including glucose transporter one and sodium-neutral amino acid transporter one, after Sem treatment. In addition, Sem injection led to a notable reduction in the capillary area, number, and surface densities within the labyrinth. These findings underscore the crucial role of modulating circulating GLP-1 levels in maternal adaptation, emphasizing the inhibitory effects of excessive GLP-1 receptor activation on both placental development and fetal growth.NEW & NOTEWORTHY Our study reveals a progressive decline in maternal blood glucagon-like peptide 1 (GLP-1) concentration. GLP-1 receptor agonist injection in late pregnancy significantly reduced fetal body weight, even after restoration of maternal blood glucose concentration. GLP-1 receptor activation significantly reduced the placental labyrinth area, expression of some nutrient transporters, and capillary development. Our study indicates that reducing maternal blood GLP-1 levels is a physiological adaptation process that benefits placental development and fetal growth.

Influence of doxycycline administration on rat embryonic development during organogenesis.

This experiment was performed to evaluate the possible embryotoxic and teratogenic effects of doxycycline during rat development. Twenty-one female rats were used and distributed into three groups equally (seven animals/group). The low dose group received doxycycline ata dose of 5 mg/kg bw/day orally from the 6th to 14th day of gestation. The high dose group received 10 mg/kg bw/day orally for the same period, the Control group received 1 mL distilled water orally for the same period. The dams were dissected on the 20th day of gestation and their fetuses were subjected to morphological, skeletal, and histological examination. Moreover, DNA damage analysis of liver cells of pregnant rats and their fetuses or fetal skull was assessed by Comet assay. The obtained results showed a significant decrease in fetal body weight, several morphological anomalies, and severe lack of ossification on the skull bones, phalanges, and sternum bone as well as shortness in the ulna and radius bones. Histological studies of pregnant rats revealed congestion and dilatation of the central vein of the liver lobules and fatty degeneration of the hepatocytes. In addition, 20 day-fetuses showed a marked increase of necrotic hepatocytes associated with an increased average of megakaryocytes and periportal leukocytic infiltration. Moreover, doxycycline induced a significant increase in the percentage ofDNA damage and tail length of examined samples. Conclusively, doxycycline caused certainfetal abnormalities, so it is advisable to avoid using this drug during pregnancy.

Toxic effects of maternal exposure to silver nanoparticles on mice fetal development during pregnancy.

Silver nanoparticles (SNPs) are being increasingly used in medical and industrial products. The aim of the present study was to evaluate the toxic effect of maternal exposure to SNP (1 mg/kg/day, 70 nm) on fetal development during the first and second weeks of pregnancy. Twenty-four pregnant mice were divided into four groups. SNP was administered by oral gavage on gestational days (GD) 1-7, GD8-14, or GD1-14. Phosphate buffered saline was administered by oral gavage to a control group. On GD15, the uteri were excised, and fetal bodies and placentas were weighed. Head and placental circumferences and fetal crown-rump length were measured, and fetuses were evaluated for external malformation. TUNEL assay was performed to assess apoptosis in the fetal midbrain. Hematoxylin-eosin staining was carried out to determine changes in fetal histomorphology. Fetal liver cells were used for karyotype analysis. Significant decreases in fetal body weight, and crown-rump length were observed in SNP-treated groups. Exencephaly, small head, scoliosis, lordosis, short thorax and trunk, also fused digits were detected in SNPs-treated groups. Fibrosis, necrosis, and apoptotic cells in fetal midbrains increased significantly in the GD8-14 and GD1-14 groups compared to the control group. Chromosomal features were not different in fetuses between groups. Exposure to 1 mg/kg/day SNP during pregnancy in mice adversely affected on fetal development. The results do suggest a potential risk for humans that needs to be followed up with more definitive investigations.

Exposure of pregnant mice to triclosan impairs placental development and nutrient transport

Triclosan (TCS) is associated with spontaneous abortions and fetal growth restriction. Here, we showed that when pregnant mice were treated with 8 mg/kg TCS (8-TCS mice) on gestational days (GD) 6–18 fetal body weights were lower than controls. Placental weights and volumes were reduced in 8-TCS mice. The placental proliferative cells and expression of PCNA and Cyclin D3 on GD13 were remarkably decreased in 8-TCS mice. The decreases in activities and expression of placental System A amino acid or glucose transporters on GD14 and GD17 were observed in 8-TCS mice. Levels of serum thyroxine (T4) and triiodothyronine (T3) were lower in 8-TCS mice than those in controls. Declines of placental Akt, mTOR and P70S6K phosphorylation in 8-TCS mice were corrected by L-thyroxinein (T4). Treating 8-TCS mice with T4 rescued the placental cell proliferation and recovered the activity and expression of amino acid and glucose transporters, which were sensitive to mTOR inhibition by rapamycin. Furthermore, the replacement of T4 could rescue the decrease in fetal body weight, which was blocked by rapamycin. These findings indicate that TCS-induced hypothyroxinemia in gestation mice through reducing Akt-mTOR signaling may impair placental development and nutrient transfer leading to decreases in fetal body weight.

Effects of intrauterine retention and postmortem interval on body weight following intrauterine death: implications for assessment of fetal growth restriction at autopsy.

According to the classification system used, 15-60% of stillbirths remain unexplained, despite undergoing recommended autopsy examination, with variable attribution of fetal growth restriction (FGR) as a cause of death. Distinguishing small-for-gestational age (SGA) from pathological FGR is a challenge at postmortem examination. This study uses data from a large, well-characterized series of intrauterine death autopsies to investigate the effects of secondary changes such as fetal maceration, intrauterine retention and postmortem interval on body weight. Autopsy findings from intrauterine death investigations (2005-2013 inclusive, from Great Ormond Street Hospital and St George's Hospital, London) were collated into a research database. Growth charts published by the World Health Organization were used to determine normal expected weight centiles for fetuses born ≥ 24 weeks' gestation, and the effects of intrauterine retention (maceration) and postmortem interval were calculated. There were 1064 intrauterine deaths, including 533 stillbirths ≥ 24 weeks' gestation with a recorded birth weight. Of these, 192 (36%) had an unadjusted birth weight below the 10th centile and were defined as SGA. The majority (86%) of stillborn SGA fetuses demonstrated some degree of maceration, indicating a significant period of intrauterine retention after death. A significantly greater proportion of macerated fetuses were present in the SGA population compared with the non-SGA population (P = 0.01). There was a significant relationship between increasing intrauterine retention interval and both more severe maceration and reduction in birth weight (P < 0.0001 for both), with an average artifactual reduction in birth weight of around -0.8 SD of expected weight. There was an average 12% reduction in fetal weight between delivery and autopsy and, as postmortem interval increased, fetal weight loss increased (P = 0.0001). Based on birth weight alone, 36% of stillbirths are classified as SGA. However, fetuses lose weight in utero with increasing intrauterine retention and continue to lose weight between delivery and autopsy, resulting in erroneous overestimation of FGR. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Aluminium induced Intrauterine Growth Retardation - an experimental study

Present study was carried out to determine the effect of aluminum containing antacid on the intrauterine growth and development of fetus. The duration of exposure was also correlated with the effects on fetal morphology and their weights. Seventy-two pregnant mice were given a daily i.e., dose of 0.7mg/100g of aluminum sulphate for various periods according to the grouping of experimental design. This dose was equivalent to maximum therapeutic dose of aluminum salt for a 70 kg man i.e. 5000mg aluminum/day. Fetal examination was performed on day 20 of gestation. The number of live and dead fetuses in the treated animals was not significantly different from the control groups. Therefore embryo lethality of aluminum cannot be induced. However there was a decrease in fetal body weight that was directly related to the duration of exposure to aluminum sulphate solution. Dissecting microscopic examination showed, the development was arrested in the groups exposed to drugs for longer periods. These results revealed that aluminum is a type of heavy metal, which is teratogenic for mammals even in doses, which are nontoxic for adults.

Effects of maternal subtotal nephrectomy on the development of the fetal kidney: A morphometric study.

The present study was designed to explore if maternal subtotal (5/6) nephrectomy affects the development of fetal rat kidneys using morphometric methods and examining whether there are any apoptotic changes in the fetal kidney. To generate 5/6 nephrectomized model rats, animals underwent 2/3 left nephrectomy on gestation day (GD) 5 and total right nephrectomy on GD 12. The fetal kidneys were examined on GDs 16 and 22. A significant decrease in fetal body weight resulting from maternal 5/6 nephrectomy was observed on GD 16, and a significant decrease in fetal renal weight and fetal body weight caused by maternal nephrectomy was observed on GD 22. Maternal 5/6 nephrectomy induced a significant increase in glomerular number, proximal tubular length, and total proximal tubular volume of fetuses on GD 22. Maternal 5/6 nephrectomy resulted in an increase in the number of apoptotic cells in the metanephric mesenchyme of the kidney on GD 16, and in the collecting tubules on GD 22. These findings suggest that maternal 5/6 nephrectomy stimulates the development of the fetal kidney while suppressing fetal growth.

Protective Effect of Olive Oil against Teratogenecity Induced by Mancozeb in Albino Rats

Aim: this study aimed to investigate the protective effect of extra-virgin olive oil (EVOO) against teratogenicity of the fungicide mancozeb. Methods: after pregnancy confirmation, 32 pregnant rats were divided into 4-groups (n=8). The 1st group orally administered tap water (-ve control), the 2nd group (+ve control) was administered EVOO (0.5ml/dam) from the1st to 20th day of pregnancy. The 3rd and the 4th groups were administered 200 mg/kg mancozeb during the period of organogenesis, from the 6th to 15th day of pregnancy. The 4th group received the mentioned dose of EVOO prior to the pesticide administration. Cesarean section was performed on day 20 of pregnancy and the maternal and fetal parameters were recorded. Results: mancozeb induced maternal toxicity manifested as lower body weight gain of dams, increased number of late resorption sites/litter in comparison with the control group and mancozeb group pretreated with EVOO. Mancozeb evoked a decrease in fetal body weight, altered sex ratio (M/F) as well as increased incidence of fetal external, visceral and skeletal abnormalities. Treatment with virgin oil reduced the congenital malformations. Conclusively, the present study elucidates the protective role of EVOO as a result of antioxidant activity which scavenges the reactive oxygen species which induced cytotoxicity and increased prenatal mortalities.

Influence of mefloquine administration during early pregnancy on rat embryonic development

Mefloquine (MQ) is a potent effective antimalarial drug against multiple drug-resistant Plasmodium falciparum. It has been proved that MQ can be given safely during the second and third trimesters. However, there is very limited information on the drug safety during the first trimester. The aim of the present work was to investigate the embryotoxicity and teratogenicity of MQ during critical periods of early development. Wistar rats were orally administered with a single dose of MQ (45 mg/kg bwt or 187 mg/kg bwt) on the 1st, 6th or 13th days of pregnancy. Cyclophosphamide (CPA) was chosen as a positive control. On the 21st day of gestation, standard parameters of reproductive performance and fetal examination were estimated. Malondialdehyde (MDA) level, glutathione reductase activity and glutathione (GSH) content were evaluated in placenta and liver homogenates of mothers and fetuses. The results indicated that MQ did not adversely affect the number of implantation, resorption, litter size and fetal body weight and length. Only groups treated with MQ on the 1st day of gestation exhibited significant decrease in fetal body weight. Examination of fetuses for external, visceral and skeletal changes showed minimal variations involving extension of lateral brain ventricles and renal pelvis and signs of delayed ossification. These variations were accompanied with significant elevation of MDA level and reduction of GSH content of fetal liver. Prenatal exposure to MQ at early pregnancy did not cause any embryolethal or teratogenic effect. It could slightly exacerbate minor variations.

The role of Pectin in controlling the changes induced by Mercuric Chloride in albino rats fetuses

The present work was planned to investigate the role of Pectin in ameliorating the morphometric, morphological and skeletal changes induced by mercury in albino rat's fetuses. 50 Wistar wistar virgin female rats were used in the present study and 25 males for mating. The results of the present work showed that the exposure of the pregnant rats to mercury chloride at a dose 5mg/kg body weight lead to significant decrease in fetal body weights as well as body and tail lengths. Also, mercury chloride administration of the pregnant rats resulted in some changes in experimental morphology of the fetuses. In addition, the fetal skeletal system was affected as follows; increase of the number of non ossified bones in the axial and peripheral systems. Pectin treatment of the pregnant rats improved the fetuses’ morphometric, morphological and skeletal changes.:

The role of Pectin in controlling the changes induced by Mercuric Chloride in albino rats fetuses

The present work was planned to investigate the role of Pectin in ameliorating the morphometric, morphological and skeletal changes induced by mercury in albino rat's fetuses. 50 Wistar wistar virgin female rats were used in the present study and 25 males for mating. The results of the present work showed that the exposure of the pregnant rats to mercury chloride at a dose 5mg/kg body weight lead to significant decrease in fetal body weights as well as body and tail lengths. Also, mercury chloride administration of the pregnant rats resulted in some changes in experimental morphology of the fetuses. In addition, the fetal skeletal system was affected as follows; increase of the number of non ossified bones in the axial and peripheral systems. Pectin treatment of the pregnant rats improved the fetuses’ morphometric, morphological and skeletal changes.:

Fetal adrenal development: Comparing effects of combined exposures to PCB 118 and PCB 153 in a sheep model

This study investigated the effects of exposure to the ubiquitous contaminants polychlorinated biphenyls (PCBs) on the fetal adrenal cortex and on plasma cortisol using the domestic sheep (Ovis aries) as a model. Pregnant ewes were intendedly subjected to oral treatment with PCB 153 (98 μg/kg bw/day), PCB 118 (49 μg/kg bw/day) or the vehicle corn oil from mating until euthanasia on gestation day 134 (±0.25 SE). However, because of accidental cross-contamination occurring twice causing a mixed exposure scenario in all three groups, the focus of this paper is to compare three distinct groups of fetuses with different adipose tissue PCB levels (PCB 153high, PCB 118high and low, combined groups) rather than comparing animals exposed to single PCB congeners to those of a control group. When comparing endocrine and anatomical parameters from fetuses in the PCB 153high (n = 13) or PCB 118high (n = 14) groups with the low, combined group (n = 14), there was a significant decrease in fetal body weight (P < 0.05), plasma cortisol concentration (P < 0.001) and adrenal cortex thickness (P < 0.001). Furthermore, adrenal weight was decreased and plasma ACTH was increased only in the PCB 118high group. Expression of several genes encoding enzymes and receptors related to steroid hormone synthesis was also affected and mostly down-regulated in fetuses with high PCB tissue levels. In conclusion, we suggest that mono-and di-ortho PCBs were able to interfere with growth, adrenal development and cortisol production in the fetal sheep model. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.

Prenatal developmental toxicity studies of inhaled methyl iodide vapor in rabbits reveal a susceptible window of exposure inducing late gestational fetotoxicity

Methyl iodide (MeI), an intermediate used in the manufacture of some insecticides and pharmaceuticals, is under review for U.S. registration as a non-ozone-depleting alternative to methyl bromide in the pre-plant soil fumigation market. Guideline (OPPTS 870.3700) developmental toxicity studies in New Zealand White (NZW) rabbits showed dose-dependent increases in the litter proportions of late fetal deaths and postimplantation loss and/or decreased fetal body weight following inhalation exposure of pregnant rabbits to MeI during gestation days (GD) 6–28. A subsequent phased-exposure study was performed to pinpoint the critical window of gestational exposure that produced the rabbit fetotoxicity. Artificially inseminated NZW female rabbits were exposed to 20 ppm MeI vapors by whole-body inhalation (6 h/day) throughout major organogenesis and fetal development (GD 6–28), during early gestation (GD 6–14) or mid-gestation (GD 15–22) only, or during 2-day intervals late in gestation (GD 23–24, 25–26, or 27–28). No maternal or developmental toxicity was elicited from maternal exposure during GD 6–14, 15–22, or 27–28. However, MeI-related fetotoxicity, including increased litter proportions of late fetal deaths with or without corresponding decreases in fetal body weight, were observed for females exposed during GD 6–28 (p < .01), 23–24 and 25–26. Although the increase in late-stage fetal death for each of the 2-day exposures on GD 23–24 and GD 25–26 was not statistically significant, as noted for the combined total of fetal deaths during the GD 6–28 exposure, it can be deduced that the gestational window of GD 23–26 was the most susceptible window of exposure for eliciting developmental toxicity in rabbits exposed to MeI vapors.

Developmental toxic potential of 1,3-dichloro-2-propanol in Sprague–Dawley rats

This study investigated the potential adverse effects of 1,3-dichloro-2-propanol (1,3-DCP) on pregnant dams and the embryo-fetal development after maternal exposure on gestational days (GD) 6 through 19 in Sprague–Dawley rats. The test chemical was administered to pregnant rats by gavage at dose levels of 0, 10, 30, and 90 mg/kg per day ( n = 10 for each group). All dams underwent Caesarean sections on GD 20, and their fetuses were examined for morphological abnormalities. Maternal toxicity was noted at 90 mg/kg/day. Manifestations of toxicity included clinical signs of illness, lower body weight gain, decreased food intake, and increases in the weight of the adrenal glands and the liver. Developmental toxic effects including decreases in fetal body weight and increases in visceral and skeletal variations also occurred at the highest dose. At 30 mg/kg, only a minimal maternal toxicity, including a decrease in maternal food intake and an increase in the liver weight, was observed. No adverse maternal or developmental effects were observed at 10 mg/kg/day. These results revealed that a 14-day repeated oral dose of 1,3-DCP was minimally embryotoxic but not teratogenic at a maternal toxic dose (90 mg/kg/day), and was not embryotoxic at a minimally maternal toxic dose (30 mg/kg/day) in rats. Because the developmental toxicity of 1,3-DCP was observed only in the presence of maternal toxicity, it is concluded that the developmental findings observed in the present study are secondary effects to maternal toxicity. Under these experimental conditions, the no-observed-adverse-effect level of 1,3-DCP is considered to be 10 mg/kg/day for dams and 30 mg/kg/day for embryo-fetal development.

The Herbal Medicine Tokishakuyakusan Increases Fetal Blood Glucose Concentrations and Growth Hormone Levels and Improves Intrauterine Growth Retardation Induced by Nω-Nitro-L-arginine Methyl Ester

Nω-Nitro-L-arginine methyl ester (L-NAME) induces a pre-eclampsia-like syndrome in pregnant rats. We have previously reported the anti-hypertensive effects of several Japanese traditional (Kampo) medicines in this model, and one of these, Tokishakuyakusan (TS), also improved intrauterine growth retardation (IUGR). In the present study, we characterized the effect of TS on IUGR. TS administration reversed the decrease in fetal body weight and fetal blood glucose concentration induced by the infusion of L-NAME. Growth hormone (GH) levels in the fetal blood, which were decreased by L-NAME infusion, were also significantly elevated by TS; however, levels of GH releasing hormone (GHRH) and insulin-like growth factor I (IGF-I) were unchanged and only slightly changed, respectively. Treatment with L-NAME with or without TS had no apparent effect on GH, GHRH, and IGF-I levels of dams. In an immunocytochemical study, the number of GH-positive cells in the fetal pituitary gland was significantly increased in TS-treated rats. These data suggest that enhanced proliferation of somatotrope cells of the pituitary gland and the resultant increase in GH secretion in the fetus may be involved in the improvement of IUGR by TS.

Skeletal muscle glucose transporter protein responses to antenatal glucocorticoids in the ovine fetus

We investigated the effects of maternal antenatal dexamethasone (Dex) treatment given as a single course (4 doses) or multiple courses (20 doses) on fetal skeletal muscle glucose transporter (GLUT) protein concentrations at 70% of gestation (106 to 107 days with term being 145 to 150 days) in the ovine fetus. Antenatal corticosteroid administration was associated with a decrease in endogenous fetal plasma cortisol concentrations (P < 0.05), fetal hyperglycemia (P < 0.02) and hyperinsulinemia (P < 0.05). These metabolic/hormonal changes were associated with a decrease in fetal body weight (P < 0.05) in the multiple course Dex group compared with the multiple course placebo group. These perturbations were associated with an increase in fetal skeletal muscle GLUT 1 concentrations that mediate basal glucose transport in the extensor digitorum lateralis and extensor digitorum longus muscles (P < 0.05) 18 h after the last dose of Dex was given in the single course group. However, in the multiple course Dex group, a small increase in GLUT 1 was observed only in the biceps femoris. In contrast, both single and multiple courses of antenatal Dex were associated with an increase in the extensor digitorum lateralis and biceps femoris muscle GLUT 4 (insulin-responsive) concentrations (P < 0.05). We conclude that antenatal corticosteroids perturb fetal glucose/insulin homeostasis, which is associated with increases in fetal skeletal muscle glucose transporters to compensate for and attenuate the associated catabolic fetal state. These changes consist of an increase in proteins that mediate basal glucose transport (GLUT 1) to meet immediate energy requirements of the fetal skeletal muscle with an increase in basal insulin sensitivity (GLUT 4) to compensate for the Dex-induced catabolic state after exposure to multiple courses of Dex.

Effects of an antisense oligonucleotide inhibitor of human ICAM‐1 on fetal development in rabbits

The potential for reproductive toxicity of an antisense oligonucleotide designed to inhibit ICAM-1 was evaluated as part of the safety assessment for this compound. The human active ICAM-1 inhibitor (ISIS 2302) is not pharmacologically active in rabbits. Female rabbits were treated once daily on Day 6 through 18 of gestation. Rabbits were treated with 0, 1, 3, and 9 mg/kg ISIS 2302 by daily i.v. injection. Reproductive indices evaluated included estrus cycling, litter parameters, fetal development, and fetal body weight. Concentrations of oligonucleotide in plasma following the last dose, and in selected maternal target organs, placenta, and fetal tissues at scheduled necropsy were also measured. Maternal toxicity was evident as a decreased maternal body weight gain, decreased food consumption, and scant feces at doses > or =3 mg/kg. Increased spleen to body weight ratio and increased mononuclear cell infiltrates were indicative of a proinflammatory effect of ISIS 2302 at the 9 mg/kg dose level. Despite the maternal toxicity, there were no changes in litter parameters or fetal development in rabbits treated with ISIS 2302. The only change was a decrease in fetal body weight at the 9 mg/kg dose level, which was attributed to the maternal toxicity observed. Maternal liver and kidney contained dose-dependent concentrations of oligonucleotide, but there was relatively little or no oligonucleotide measured in placenta or fetal tissues. Thus, there was no dose-dependent exposure and maternal toxicity to ISIS 2302, but no reproductive toxicity in rabbits, and exposure of fetus or pups is negligible.

The herbal medicine Toki-shakuyaku-san improves the hypertension and intrauterine growth retardation in preeclampsia rats induced by Nomega-nitro-L-arginine methyl ester.

The chronic inhibition of nitric oxide (NO) synthesis with Nomega-nitro-L-arginine methyl ester (L-NAME) induces a preeclampsia-like syndrome including hypertension and intrauterine growth retardation (IUGR) in pregnant rats. We tested the traditional herbal medicine Toki-shakuyaku-san (TS) for beneficial effects in this model. L-NAME was infused subcutaneously into pregnant rats from day 14 of gestation. TS (1 g/kg, 2 g/kg) was administered by gavage from day 14 to 20. Systolic blood pressure was measured on day 19. On day 20, rats were sacrificed and serum NO levels, placental weight, fetal body weight, fetal cerebrum weight and the thickness of the cerebral cortex were analyzed. TS (1 g/kg, 2 g/kg) inhibited L-NAME-induced hypertension. The decrease in fetal body weight, cerebrum weight and thickness of the cerebral cortex was abrogated by TS (2 g/kg). The effect of TS on blood pressure was found only in the rats that were both pregnant and infused with L-NAME. L-arginine, at the amount equivalent to that contained in TS, showed no effect. Further, the change in serum NO levels induced by TS was only marginal. TS thus improved the hypertension and IUGR in preeclampsia rats induced by L-NAME in a NO-independent manner. These data suggested that TS may be beneficial for the treatment and prevention of preeclampsia.

Developmental toxicities of ethylbenzene, ortho-, meta-, para-xylene and technical xylene in rats following inhalation exposure

The developmental toxicities of ethylbenzene, o-, m-, p-xylene and technical xylene were studied in Sprague–Dawley rats after inhalation exposure. Animals were exposed to either of these agents at 100, 500, 1000 or 2000 ppm, for 6 h/day, during days 6–20 of gestation. All the agents tested caused maternal toxicity expressed as a reduction in maternal body weight gain at 1000 and 2000 ppm. Decreased corrected weight gain and food consumption were observed at 1000 and 2000 ppm ethylbenzene, o-, m- or p-xylene, and at 2000 ppm technical xylene. No evidence of teratogenic effects was found after exposure to any of these agents up to 2000 ppm. Fetal toxicity evidenced by significant decreases in fetal body weights occurred at concentrations of 500 ppm or greater of o-xylene or technical xylene, and 1000 ppm or greater of ethylbenzene, m- or p-xylene. A significant increase in the mean percentage of fetuses per litter with skeletal variations was also noted at 2000 ppm ethylbenzene, o- and p-xylene. In summary, all tested agents produced developmental toxicity at 1000 and 2000 ppm, concentrations that also produced significant maternal toxicity. With o-xylene and technical xylene, developmental toxicity also occurred at 500 ppm, in the absence of maternal toxic effects. However, the only indication of a treatment-related effect was a slight decrease in fetal weight.

Effects of maternal ethanol consumption on hematopoietic cells in the rat fetal liver

During development, there are many factors to be considered in studying the efficacy of the hematopoietic system to provide the immune system with adequate numbers of functional cells within the immune repertoire. Hematopoietic cells must be able to develop, proliferate, and emigrate from the hematopoietic fetal liver to other tissues of the body, such as the thymus and bone marrow. There is evidence that ethanol consumption causes immune deficiencies in adults and that maternal ethanol consumption causes immune deficiencies in children, both with correlative effects on cells and cytokinetic regulators. Therefore, the ability of the hematopoietic system to seed the immune system may be jeopardized by maternal ethanol consumption. In this study, test groups included female rats (1) fed a Lieber–DeCarli ethanol liquid diet, (2) pair-fed a control liquid diet, or (3) fed standard laboratory chow. Livers were removed from fetuses 18 and 21 days postconception (dpc) and analyzed by immunophenotyping and flow cytometry. There was a 22% and 38% decrease in fetal body weight and a 25% and 30% decrease in fetal liver weights between ethanol-fed and pair-fed groups at 18 and 21 dpc, respectively. At 18 dpc, fetal body and liver weights of the pair-fed animals were also significantly reduced to those of the chow-fed group. However, by 21 dpc, both body and liver weights of the two control groups were not statistically different. The effects of maternal ethanol consumption on the distribution of hematopoietic cells were characterized by using monoclonal antibodies (mAbs) anti-CD43 (a progenitor hematopoietic cell marker) versus labeling with anti-Vβ8.2 (pre-T cells), anti-B220 (pre-B cells), and anti-NKR-P1A (pre-natural killer cells). With the use of flow cytometric analysis, at 18 dpc ethanol-exposed fetuses showed 40% and 62% decreases in B220 + and Vβ8.2 + cells, respectively, versus findings for pair-fed controls, with no significant change in NKR-P1A + cells. At 21 dpc, ethanol-exposed fetuses showed a 46% decrease in B220 + cells among the CD43 + cells, with a 50% increase in Vβ8.2 + cells. Observed alterations in gross fetal body and liver weights, together with modifications in the percentage of hematopoietic cells in the fetal liver after maternal ethanol consumption, strongly support the suggestion that the ability of the hematopoietic system to impart a repertoire of cells that are functional in the regulatory and effector mechanisms of the immune process may be compromised.