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This study was designed to determine precisely the radiosensitive period in the development of ICR mouse embryos during which external malformations and growth retardation tend to occur. Female and male mice were placed together for only three hours to allow fairly precise identification of the time of conception. The pregnant mice were divided into 31 groups, which were irradiated in turn with 1.5 Gy gamma radiation at 6-hour intervals during the period of organogenesis. They were then observed on day 18 of gestation. Items recorded were intrauterine death, external malformations, sex ratio and fetal body weight. Death of the embryo/fetus, especially death in the early period of organogenesis, was most frequent in mice irradiated between days 6.75 and 8.25 of gestation, but there was no statistically significant difference in the frequency of early- and late-period deaths between irradiated and control groups. The types and frequencies of external malformations observed differed according to the exposure period. The most highly sensitive period for each malformation lasted no more than 12 hours. Reduction of fetal body weight was a good indicator of radiation effects, and was observed mostly in the groups irradiated between days 9.75 and 11.00 of gestation. The sex ratio was not affected by the period in which irradiation was performed.

The effects of multiple maternal subcutaneous injections of uranyl acetate dihydrate (0.5, 1, and 2 mg/kg/d) from d 6 to d 15 of gestation were evaluated in Swiss mice. External, internal soft-tissue and skeletal examinations of fetuses were performed on gestation d 18. Maternal toxicity occurred in all uranium-treated groups as evidenced primarily by deaths as well as significant decreases in weight gain and in body weight at termination. Although it was not dose-related, embryotoxicity also occurred in all uranium-treated groups (significant increases in the number of nonviable implantations and in the percentage of postimplantation loss). Fetal body weight was significantly decreased at 1 and 2 mg/kg/d, whereas the number of total internal and total skeletal defects showed dose-dependent increases at 0.5, 1, and 2 mg/kg/d. Most morphological defects were developmental variations, whereas malformations were only detected at 1 and 2 mg/kg/d. On the basis of these data, both the maternal no-observable-adverse-effect level (NOAEL) and the NOAEL for embryotoxicity of uranyl acetate dihydrate were below 0.5 mg/kg/d, whereas the NOAEL for teratogenicity was 0.5 mg/kg/d.

The aim of the study was to investigate the toxic effects of hyperbaric oxygen (HBO) on rat embryos. Two groups of Fischer pregnant rats were exposed to oxygen at pressures of 324 and 426 kPa for 90 min per day for 5 consecutive days (8–12 days of gestation). The third group was exposed to normobaric oxygen for 12 h on the eighth day of gestation. Two control groups were used; the first was comprised of intact and the second of sham-treated animals. The HBO treatment did not significantly affect maternal weight gain or reduce litter size, nor did it induce any embryonic abnormalities. However, the fetal body weight was reduced and the placental weight increased in the groups exposed to HBO at pressures of 324 and 426 kPa. When female fetuses which had been exposed to oxygen at 324 or 426 kPa were compared to the intact control group, a reduction in wet weights of 9.2 (p < 0.05) and 12.1 % (p < 0.01), respectively, was noted. Male fetuses exposed to oxygen at 324 and 426 kPa displayed a reduced body weight of 11.7 (p < 0.01) and 16.6% (p < 0.01), respectively. Placental weight was increased by 18.9 (p < 0.01) and 23.6% (p < 0.01) in the groups exposed to oxygen at 324 and 426 kPa, respectively. These data suggest that HBO, either at 324 or 426 kPa, is not potent at inducing malformations and that the largest embryotoxic effects are upon fetal body weight and placental weight. However, the histological examination of placentas revealed alterations in labyrinthine blood vessels and a statistically significant thickening of the placental barrier. In conclusion, this study suggests that transient interference with normal placentation is probably sufficient to cause permanent maldevelopment of the placenta and embryo.

The oleoresin of the copaiba tree (Copaifera sp., Fabaceae) is traditionally used in Brazilian herbal medicine to treat a variety of illnesses and symptoms. This study, conducted according to the OECD Guideline 414, provides data on the developmental toxicity of oleoresin from C. reticulata (COPA-R) in rats. Pregnant Wistar rats (25 per dose group) were treated by gavage with COPA-R (0, 500, 1000 and 1250 mg/kg bw/day) on gestation days (GD) 6-19 and Caesarean sections performed on GD20. Implantations, living and dead fetuses and resorptions were recorded. Half of the fetuses from each litter were examined for visceral abnormalities and the remaining were cleared and stained for skeleton evaluation. COPA-R was maternally toxic (reduced food intake and weight gain) and embryotoxic (lower fetal body weight and increased occurrence of fetal skeleton variations) at the two highest doses, but did not cause embryo deaths or fetal malformations at any dose level. The study derived an oral no-observed-adverse-effect-level (NOAEL) for maternal and developmental toxicity induced by COPA-R of 500 mg/kg bw/day. The results suggest that copaiba oleoresin does not pose a health risk to pregnant women when used according to the recommended doses (up to five drops, three times a day).

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.

In our study, we investigated the influence of plasma levels ghrelin, leptin and other metabolic hormones (ILGF-1 and ILGF-2) in pregnants in regulating fetal body weight and mode of delivery. A total of 36 appropriately healthy pregnants 19–36-year-old were involved in the study. Demographic chracteristics, serum ghrelin, leptin, IGF-1 and IGF-2 levels of the pregnants were studied. Plasma ghrelin and leptin levels did not differ significantly among trimesters and delivery, in contrast to IGF-I and IGF-II concentrations were significantly higher in the first half of the pregnancy (P

BACKGROUND: Insulin-like growth factor (IGF) signaling has been linked to tumor cell survival and tumorigenesis. The anti-IGF-1 receptor monoclonal antibody, figitumumab, has been developed as an anti-cancer therapeutic. As part of the safety evaluation, an embryo-fetal developmental toxicity study was conducted in the cynomolgus monkey. METHODS: Figitumumab was administered once weekly intravenously at a dose of 5, 15, or 100 mg/kg during the period of major organogenesis (gestation days [GD] 20–48) with scheduled cesarean section around GD100. Maternal endpoints included clinical observations, food consumption, body weights, hematology, placental weights, toxicokinetics, and immunogenicity. Fetal evaluations included viability; body weights; external, visceral, and skeletal examination (and measurements); drug exposure; and immunogenicity. RESULTS: There was a dose-dependent increase in embryo-fetal loss in the presence of decreased maternal food consumption and slight reduction in body weight. Figitumumab-related embryo-fetal developmental toxicity was observed as growth retardation exhibited by reduced fetal body weights at all doses with corresponding developmental delays in morphology. Treatment-related fetal structural malformations were also observed in the mid- and high-dose groups. CONCLUSIONS: Maternal figitumumab dosing only during the period of organogenesis was associated with pregnancy loss and fetal growth deficits; both considered consistent with inhibition of IGF signaling. Fetal malformations were also observed, and were considered secondary to altered placental function and/or reduced fetal growth; however, direct inhibition of IGF signaling in the conceptus cannot be ruled out. This appears to be the first report of treatment-related fetal anomalies with a monoclonal antibody when administered only during the period of major organogenesis. Birth Defects Res (Part B) 89:326–338, 2010.© 2010 Wiley-Liss, Inc.

BACKGROUND: Ginseng has been used for a long time and is well tolerated in humans. However, recent studies have shown that ginsenosides Rb1, Rg1, and Re exert embryotoxicity in in vitro culture systems. We investigated the effects of Korean red ginseng extract (KRGE) on embryonic implantation and fetal development in mice. METHODS: Mice were orally administered KRGE (20, 200, or 2,000 mg/kg/day) from 2 weeks before mating to gestational day (GD) 18, and implantation rate, fetal mortality, body weights, as well as external, visceral, and skeletal abnormalities were determined by Caesarean section on GD18. Ginsenosides in KRGE and in the blood of dams were identified and quantified by HPLC analysis. RESULTS: KRGE did not affect embryonic implantation and mortality as well as fetal body weights up to 2,000 mg/kg/day (≈200 times clinical doses), the upper-limit dose recommended by the Korea Food and Drug Administration (KFDA). Although the prevalence of supernumerary ribs increased at the medium dose (200 mg/kg/day), no dose-dependent increases in external, visceral, and skeletal abnormalities were observed. Major ginsenosides such as Rb1, Rg1, and Re were not detected in the blood of dams based on their chromatographic profiles. CONCLUSIONS: Considerable developmental toxicities of KRGE, even at the upper-limit dose, were not observed in mice. These results might be due to the negligible blood concentrations of ginsenosides in their original forms following oral administration, suggesting that in vitro experiments to assess the effects of ginsenosides on embryotoxicity may not reliably explain the risks of ginsenosides to in vivo embryo-fetal development. Birth Defects Res (Part B) 89:78–85, 2010. © 2010 Wiley-Liss, Inc.

The search for a carnivore as an addition to a multilevel test system for determining developmental toxicity has been extended to include the ferret. The following discussion is an effort to simplify the procedures which should be used with this species when conducting a typical Segment II - Teratology Study and to reduce the uncertainties which always accompany the introduction of a different animal model. It is recommended that developmental toxicity studies in ferrets include a positive control group. All-trans retinoic acid (15 mg/kg on day 14 of gestation) had minimal effects on the dam and her pregnancy and maximal effects on the fetus. Administration of retinoic acid did not alter maternal weight or weight gain nor affect the average numbers of corpora lutea, implantations, resorptions or litter sizes. It did, however, reduce fetal body weight, produce gross external alterations in 90.6% of the fetuses and increase the skeletal alterations (particularly of the skull) in the exposed fetuses as compared with controls. Timed pregnant ferrets may be received from a supplier within a day or two after mating without interfering with implantation which occurs on day 12. Intubation with the test article is conducted throughout organogenesis from day 12 to day 30 with sacrifice on day 35 of gestation. Examination of the ferret fetuses is similar to that conducted with rat fetuses.

To determine the potential developmental toxicity of hydroquinone (HQ), pregnant rats (COBS-CD-BR) were given 0, 30, 100, or 300 mg/kg HQ by gavage on the 6th through the 15th days of gestation. Maternal effects included a slight, but significant (p ≤ 0.05), reduction in body weight gain and feed consumption for the 300 mg/kg HQ dams. Reproductive indices, i.e., pregnancy rate, numbers of corpora lutea, implantation sites, viable fetuses, and early and late resorptions, fetal sex ratio, pre- and postimplantation losses, and gravid uterine weights, were not affected by treatment with HQ. A slightly reduced (p ≤ 0.05) mean fetal body weight seen at the 300 mg/kg dose level was associated with the slightly reduced body weight gain seen for the dams at this dose level. Gross external, internal soft tissue, and skeletal examinations of the fetuses revealed no HQ-related malformations. The incidences of gross external variations (small hematomas) and internal soft tissue variations (dilated renal pelvis, hydronephrosis, and hydroureter) in the HQ-treated litters were not statistically different from the control incidences. Skeletal variations (delayed ossification of membranous skull bones, hyoid bone, thoracic centra 1–3, sacral arches 3 and 4, and bilobed thoracic centra 9–13) were seen with similar frequency in the control and HQ-treated groups. A statistically significant increase in the incidence of total common vertebral variations seen at the 300 mg/kg HQ dose level was not considered toxicologically significant. The incidences of total skeletal variations were not statistically different between the control and the HQ-treated groups. It is concluded that HQ was not selectively toxic to the developing rat conceptus and, thus, appears not to have the properties of a developmental toxicant. The no-observable-effect level for both maternal and developmental toxicity was 100 mg/kg, whereas 300 mg/kg was the no-observable-adverse-effect level.

Boric acid (BORA), an ingredient of many cosmetics, pharmaceuticals, and pesticides, was tested for developmental toxicity in timed-pregnant Swiss mice and Sprague-Dawley rats (n = 26-28/group). BORA (0, 0.1, 0.2, or 0.4% in feed) was provided throughout gestation to attain steady-state exposure as early as possible during prenatal development. Average doses (mg/kg/day) were 248, 452, or 1003 in mice, and 78, 163, or 330 in rats. To limit prenatal mortality, BORA (0.8% or 539 mg/kg/day) was provided to an additional group of rats on Gestational Days (GD) 6 to 15 only. On GD 17 (mice) or 20 (rats), fetuses were weighed and examined for malformations (external, visceral, skeletal). Mouse dams exhibited mild renal lesions (greater than or equal to 0.1%), increased water intake and relative kidney weight (0.4%), and decreased weight gain (0.4%) during treatment. There was a reduction of fetal body weight (greater than or equal to 0.2%) and an increased incidence of resorptions and malformed fetuses per litter (0.4%). Morphological changes included an increased incidence of short rib XIII (a malformation) and a decreased incidence of rudimentary or full rib(s) at lumbar I (an anatomical variation). Maternal rats exhibited increased liver and kidney weights at greater than or equal to 0.2%, altered water and/or food intake at greater than 0.2%, and decreased weight gain at greater than 0.4%. Average fetal body weight/litter was reduced at all doses. Prenatal mortality was increased only at 0.8%. The incidence of fetal malformations was significantly increased at greater than or equal to 0.2%. The most frequently observed malformations were enlarged lateral ventricles of the brain and agenesis or shortening of rib XIII. In rats, the no-observable-adverse-effect level (NOAEL) for maternal toxicity was 78 mg/kg (0.1%), while in mice the low dose of 248 mg/kg (0.1%) approached the maternal NOAEL with mild renal lesions in only 2 of 10 females. Embryo/fetal toxicity occurred in all groups of rats at greater than or equal to 78 mg/kg (greater than or equal to 0.1%) while the NOAEL for developmental toxicity in mice was 248 mg/kg (0.1%). Thus developmental toxicity occurred below maternally toxic levels in rats as well as in the presence of maternal toxicity in mice and rats.

Virtually continual exposure to 970-MHz microwaves in circularly-polarized waveguides was used to elicit fetal responses in Sprague-Dawley rats during gestation. A total of 250 rats were exposed to microwave radiation at whole-body averaged specific absorption rates (SAR) of 0.07, 2.4, or 4.8 W/kg or concurrently sham-irradiated for 22 h/day from the 1st through the 19th day of gestation. Prior to irradiation or sham irradiation, the rats were acclimated to cages in the waveguide system for 10 days and then bred. The rats were killed on the 20th day of gestation, and their fetuses counted and weighed, the fetal sternebrae ossifications counted, and the number of corpora lutea of the pregnancy determined. There were no alterations in pregnancy rates, fetal numbers (live, dead, resorbed, or total conceptuses), fetal weights, fetal skeletal maturation, or preimplantation losses after exposure at SARs of 0.07 or 2.4 W/kg. At SAR of 4.8 W/kg, only fetal body weight was significantly altered (- 12%, p = 0.012)....

Sprague-Dawley rats and Swiss (CD-1) mice were exposed to 0, 600, 1800, or 5000 ppm THF (a four-carbon cyclic ether, widely used as an industrial solvent) vapors, 6 hr/day, 7 days/week (6-19 days of gestation (DG) for rats; 6-17 DG for mice). Body weights of pregnant rats in the 5000 ppm group were reduced at euthanization. There were no effects on the percentage of live rat fetuses/litter or on the fetal sex ratio. Fetal body weight was significantly reduced for the 5000 ppm group, but the incidence of abnormalities was not increased. Mice in the 1800 and 5000 ppm groups were sedated during exposure; approximately 27% of the mice in the 5000 ppm group died. Mean body and uterine weights of mice were reduced for the 1800 and 5000 ppm groups at euthanization (18 DG), but adjusted maternal weight gain was not affected at 1800 ppm. There was a reduction in the percentage of live fetuses/litter for the mice in 1800 and 5000 ppm groups (95% resorptions in the 5000 ppm group). Fetal weight and sex ratio in mice were not affected. An increase in the incidence of reduced sternebral ossifications was correlated to THF concentration, although differences between groups were not statistically significant. There were no increases in the incidences of other malformations or variations. These results suggest that THF may be embryotoxic in mice, but if the conceptus survives, development as assessed by this experimental design continues in a normal fashion. The no-observable-adverse-effect level (NOAEL) for maternal toxicity was 1800 ppm in both rats and mice. The NOAEL for developmental toxicity was 1800 ppm in rats and 600 ppm in mice.

The teratogenic potential of a versatile solvent, N-formylpiperidine (NFP), was evaluated in the rat. Three groups of 25 mated female Sprague-Dawley rats were given 110, 220, or 440 mg/kg/day NFP in distilled water by gavage on Days 6 through 20 of gestation. A control group of 25 animals received distilled water on a comparable regimen. Maternal animals were observed daily for signs of toxicity; body weights and food consumption were measured at regular intervals throughout the study. All animals were euthanized on Gestation Day 21 and the fetuses examined for cleft palate and external abnormalities. One-half of the fetuses in each litter were examined for visceral anomalies while the remaining fetuses were examined for skeletal malformations after appropriate staining. One female in the high dosage group died on Gestation Day 12. Clinical signs of toxicity, observed in 6 females in the high dosage group, included tremors, convulsive movements, and an apparent weakness of the legs. Maternal toxicity, in terms of significantly decreased body weight and food consumption, was observed in the mid and high dosage groups. Food consumption was also significantly depressed for the first 4 days of dosing in the low dosage group. There was a significant increase in number of resorptions in the high dosage group when compared to controls. No effects were observed on other reproductive parameters. Mean fetal body weight was significantly lower in the high dosage group when compared to controls. While the incidence of fetal malformations on a litter basis was higher in the high dosage group, this change was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of Prednisolone farnesylate (PNF), a newly synthesized corticosteroid, on fetal development of the rabbit was studied. PNF was administered subcutaneously at dose levels of 0(control), 0.01, 0.05 and 0.25 mg/kg/day during the fetal organogenesis period. In the pregnant animals, PNF caused no abnormalities in clinical sign, body weight gain, food consumption, or autopsy findings at 0.01 and 0.05 mg/kg/day groups; the animals at 0.25 mg/kg/day group showed a reduction in body weight gain and food consumption. Two of 13 animals at 0.25 mg/kg/day group aborted. And hydrothorax, mucosal hemorrhage of the stomach, or fading of the liver were observed in some animals. In the fetuses, PNF was observed no abnormalities in external, visceral, or skeletal examination; slight increase of embryofetal mortality, or reduction of live fetal body weight and placental weight were observed at 0.25 mg/kg/day. The results suggest that the non-effective dose level of PNF is 0.05 mg/kg/day for pregnant females in general and reproductive toxicity, and for fetuses under the condition of this study.

BACKGROUND: Cyclophosphamide induces fetal defects through metabolic activation by cytochrome P-450 monooxygenases (CYP). The effects of piperonyl butoxide (PBO), a CYP inhibitor, on the fetal development and external, visceral, and skeletal abnormalities induced by cyclophosphamide were investigated in rats. METHODS: Pregnant rats were daily administered PBO (400 mg/kg) by gavage for 7 days (the 6th to 12th day of gestation), and intraperitoneally administered with cyclophosphamide (12 mg/kg) 4 h after the final treatment. On the 20th day of gestation, maternal and fetal abnormalities were determined by Cesarean section. RESULTS: Cyclophosphamide reduced fetal body weights by 30–40% without increasing resorption or death. In addition, it induced malformations in live fetuses: 100, 98, and 98.2% of the external (head and limb defects), visceral (cerebroventricular dilatation, cleft palate, and renal pelvic/ureteric dilatation), and skeletal (acrania, vertebral/costal malformations, and delayed ossification) abnormalities, respectively. The pre-treatment of PBO greatly decreased mRNA expression and activity of hepatic CYP2B, which metabolizes cyclophosphamide into teratogenic acrolein and cytotoxic phosphoramide mustard. Moreover, PBO remarkably attenuated cyclophosphamide-induced body weight loss and abnormalities of fetuses; score 3.57 versus 1.87 for exencephaly, 75.5% versus 42.5% for limb defects, 65.3% versus 22% for cerebroventricular dilatation, 59.2% versus 5.1% for cleft palate, score 1.28 versus 0.93 for renal pelvic/ureteric dilatation, 71.9–82.5% versus 23–45.9% for vertebral/costal malformations, and 84.2% versus 57.4% for delayed ossification in cyclophosphamide alone and PBO co-administration groups. CONCLUSIONS: These results suggest that repeated treatment with PBO may improve cyclophosphamide-induced body weight loss and malformations of fetuses by down-regulating CYP2B. Birth Defects Res (Part B) 86:402–408, 2009. © 2009 Wiley-Liss, Inc.

Background Ethanol neurobehavioural teratogenicity is a leading cause of developmental mental deficiency, in which the hippocampus is a target site of injury. The multi-faceted mechanism of ethanol teratogenicity is not completely understood. This study tested the hypothesis that chronic ethanol exposure (CEE), via chronic maternal ethanol administration, increases cytochrome P450 2E1 (CYP2E1) expression and alters hypothalamic–pituitary–adrenal (HPA) axis activity in the maternal–fetal unit during the third-trimester-equivalent of gestation. Methods Pregnant Dunkin–Hartley-strain guinea pigs received daily oral administration of ethanol (4 g ethanol/kg maternal body weight) or isocaloric-sucrose/pair-feeding (control) throughout gestation (term, about gestational day (GD) 68). On GD 45, 55 and 65, pregnant animals were euthanized 2 h after the last daily dose. Maternal and fetal body weights and fetal hippocampal brain weight were determined. Maternal and fetal samples were collected for the determination of liver CYP2E1 enzymatic activity and plasma free cortisol and ACTH concentrations. Results CEE, with maternal blood ethanol concentration of 108–124 mg/dl at 2 h after the last dose, decreased fetal hippocampal weight only at GD 65 and had no effect on fetal body weight compared with control. CYP2E1 activity increased with gestational age in the fetal liver microsomal and mitochondrial fractions. CEE increased CYP2E1 activity in the microsomal and mitochondrial fractions of maternal liver at the three gestational ages and in both hepatic subcellular fractions of the GD 65 fetus compared with control. There was a gestational-age-dependent increase in maternal and fetal plasma free cortisol concentrations, but no effect of CEE compared with control. Maternal and fetal plasma ACTH concentrations were unaffected by CEE compared with control, and were virtually unchanged during the third-trimester-equivalent that was studied. Conclusion These data demonstrate that, in the pregnant guinea pig, this CEE regimen increases liver CYP2E1 activity, without affecting HPA axis function, in the maternal–fetal unit during near-term gestation. The CEE-induced increase in liver CYP2E1 activity and potential oxidative stress in the maternal–fetal unit may play a role in the pathogenesis of ethanol teratogenicity.

The developmental toxicity of 1-(1,2,3,4,5,6,7,8-Octahydro-2,3,8,8-tetramethyl-2-naphthalenyl) ethanone (OTNE), a widely used fragrance ingredient, was evaluated in pregnant Sprague-Dawley rats (25/group) gavaged with dosages of 0 (water), 96, 240, or 480 mg/kg/d on days 7 through 17 of gestation (GDs 7–17). Rats were observed for clinical signs, abortions, premature deliveries, body weights, and feed intake. Caesarean section and necropsy were performed on GD 21. Fetuses were weighed and examined for gender, gross external changes, and soft tissue or skeletal alterations. No deaths or premature deliveries were attributed to OTNE. OTNE-related clinical signs included significantly increased incidences of excessive salivation in all 3 treatment groups, and urine-stained abdominal fur in the high dosage group. Mean body weight gains were significantly reduced by all OTNE dosages on GDs 7–10, while at 480 mg/kg/d, significant reductions continued through the remainder of the dosage period. Feed consumption generally paralleled body weight gains. Fetal body weights were reduced by 480 mg/kg/d, but not to a statistically significant degree. No fetal gross external, soft tissue, or skeletal malformations or variations were attributable to OTNE. Based on these data, maternal and developmental no-observable-adverse-effect-levels (NOAELs) of 240 mg/kg/d were established for OTNE. It was concluded that OTNE is not a developmental toxicant in rats under the conditions of this study, and that a margin of safety greater than 2700 exists between reversible developmental delays in rats and the calculated daily human exposure level of 0.086 mg/kg/d.

The objective of this study was to determine the effects of in vitro embryo production on physical development and levels of expression of mRNAs for insulin-like growth factor (IGF) ligands (IGF1, IGF2), their receptors (IGF1R, IGF2R), and IGF binding protein-2 (IGFBP2) in bovine fetuses during early gestation. In vivo embryos were recovered from superovulated Holstein cows. For production of embryos in vitro, Holstein oocytes were matured, fertilized, and subsequently cultured in M199 with 10% serum to 168 hpi. On Day 70 of gestation, fetuses (in vivo, n = 14; in vitro, n = 13) were recovered, serum samples collected, and physical measurements recorded. Semi-quantitative RT-PCR assays were used to determine the levels of expression of mRNAs for IGF1, IGF2, IGF1R, and IGF2R in fetal liver and skeletal muscle. Western blots were used to assess levels of IGFBP2 in fetal serum. Fetal body weight did not differ with treatment; however, production of embryos in vitro was associated with decreased crown-nose length and a tendency for increased paired kidney weight, which became significant when expressed on a per bodyweight basis. There was no effect of treatment on levels of IGFBP2 in fetal serum. Levels of IGF1 mRNA in fetal liver were decreased (P < 0.001) in the in vitro group. Levels of IGF2R mRNA in both liver and skeletal muscle were also decreased (P < 0.01) in fetuses from the in vitro group. In summary, fetuses at Day 70 of gestation from embryos produced in vitro had shortened crown-nose length and increased kidney weight on a per bodyweight basis, as well as decreased expression of mRNAs for IGF1 in liver and IGF2R in both liver and skeletal muscle, compared with fetuses from embryos produced in vivo. In conclusion, in vitro embryo culture was associated with subtle changes in fetal development as well as altered expression of both imprinted and non-imprinted genes.

The purpose of this experiment was to establish dose-response relationships for the effects of angiotensin II on arterial pressure, venous pressure, heart rate, and blood volume in the ovine fetus. Chronically catheterized fetal sheep at 132 +/- 1 (SE) days' gestational age were infused with angiotensin II at 4.8 +/- 1.1 (n = 7), 27.7 +/- 4.6 (n = 7), 102.2 +/- 16.7 (n = 6), or 239.0 +/- 30.9 (n = 4) ng/min/kg fetal body weight for 30 minutes. Fetal arterial pressure increased at the three highest doses. Fetal venous pressure, heart rate, and blood volume responded only at 102.2 and 239.0 ng/min/kg. At 239.0 ng/min/kg, arterial pressure increased by 17.7 +/- 1.6 mm Hg (p less than 0.00001), venous pressure increased by 1.5 +/- 0.3 mm Hg (p less than 0.0005), blood volume decreased by 7.8 +/- 2.2% (p less than 0.0001), and heart rate initially decreased by 14 +/- 4 beats/min, followed by an increase of 52 +/- 17 beats/min from control (p less than 0.0005) at the end of angiotensin II infusion. Thus this study shows that angiotensin II affected multiple fetal cardiovascular variables in a dose-dependent manner, suggesting that it is an important regulatory hormone for the entire fetal cardiovascular system.

The developmental toxicity of the potent adenosine deaminase (ADA) inhibitor, pentostatin (2′-deoxycoformycin), was investigated in pregnant rats and rabbits administered daily iv doses during organogenesis. Rats received 0, 0.01, 0.10, or 0.75 mg/kg on gestation days 6–15 and rabbits received 0, 0.005, 0.01, or 0.02 mg/kg on gestation days 6–18 and maternal and fetal parameters were evaluated on gestation day 21 (rats) or 30 (rabbits). Live fetuses were examined for external, visceral, and skeletal malformations and variations. In rats, maternal body weight gain and food consumption were significantly suppressed at doses of 0.10 and 0.75 mg/kg during the treatment period but returned to control levels during posttreatment. Increased postim-plantation loss and decreased numbers of live fetuses, litter size, and fetal body weight were observed at 0.75 mg/kg. A statistically significant increase in the incidence of vertebral malformations occurred at 0.75 mg/kg. The incidence of certain skeletal variations (extra presacral vertebrae, extra ribs, hypoplastic vertebrae) was also increased at 0.75 mg/kg. Ossification of cervical centra was reduced at 0.75 mg/kg compared with controls. In rabbits, marked maternal toxicity (death, body weight loss, and decreased food consumption) and reproductive toxicity (abortion and premature delivery) occurred in all pentostatin-treated groups. However, there were no significant effects on number of live fetuses, pre- or postimplantation loss, litter size, or fetal body weights in the animals with live litters. There was also no apparent increase in the incidence of malformations or variations in the live fetuses of pentostatin-treated rabbits. Thus, these studies demonstrate developmental toxicity of pentostatin in rats and rabbits, and teratogenicity in rats, at maternally toxic doses.

Umbilical cord length has been considered a reliable indicator of fetal movement. In this study, the effect of prenatal cocaine exposure on umbilical cord length was examined in rats. Pregnant rats were intubated with either 0 or 60 mg/kg cocaine hydrochloride daily from gestation day (GD) 14-21. Fetuses were removed via Caesarean section on GD 21 and umbilical cord length, placental weight and fetal body weight were measured. Fetuses exposed to cocaine in utero had significantly shorter umbilical cords than intubated controls, although there were no differences in placental or fetal body weights. These data suggest that prenatal cocaine exposure suppresses fetal movement, which could contribute to some of the long-term effects observed in cocaine-exposed offspring.

The effects of 24 h of reduced maternal uterine blood flow (RUBF) on relative DNA synthesis rates in different tissues and on blood glucose and lactate concentrations were studied in fetal sheep. In six sheep, RUBF was induced for 24 h, whereas in another six sheep (controls), uterine blood flow was not reduced. To estimate DNA synthesis rate, [3H]thymidine (1 mCi/kg) was injected intravenously into each fetus 8 h before the end of the 24-h experimental period. Fetal arterial oxygen saturation decreased from 59.1 +/- 3.3 to 25.7 +/- 5.6% after 1 h of RUBF and remained significantly reduced for the duration of the experiment. Fetal blood lactate concentrations were significantly increased by RUBF from 14.3 +/- 6.5 to 57.8 +/- 12.4 mg/dl at 1 h and remained elevated, whereas fetal blood glucose concentrations were not affected. A 24-h period of RUBF did not significantly alter fetal body weights, tissue weights, tissue-to-body weight ratios, or tissue DNA content. Over the last 8 h of the 24-h experimental period, RUBF was found to significantly reduce the relative rate of DNA synthesis (as assessed by [3H]thymidine incorporation into DNA) in the lung (104.7 +/- 26.6 vs. 17.1 +/- 3.1 dpm/micrograms DNA), quadriceps muscle (92.8 +/- 20.7 vs. 14.4 +/- 5.3 dpm/micrograms DNA), and thymus gland (87.5 +/- 7.1 vs. 32.9 +/- 12.2 dpm/micrograms DNA). Relative DNA synthesis rates in the fetal liver, kidney, small intestine, cerebral cortex, cerebellum, placenta, thyroid gland, and adrenal gland were not significantly affected by RUBF. In this study, we have shown that DNA synthesis was greatly reduced in selected fetal tissues (lung, quadriceps muscle, and thymus gland) by a 24-h period of RUBF, although it is not known why a reduction was only observed in these tissues.

The teratogenicity of trans-2-ene-valproic acid (300 and 400 mg/kg) was compared with that of valproic acid (VPA; 300 mg/kg) and controls (corn oil) administered by gavage to Sprague-Dawley CD rats on embryonic (E) days 7-18. At the 300 mg/kg dose, trans-2-ene-VPA produced no change in maternal weight, number of implantations, proportion of resorptions, proportion of malformations, or fetal weight. By contrast, the same dose of VPA (300 mg/kg) reduced maternal weight during gestation, increased malformations (12.0% vs. 0.7% in controls), and reduced fetal body weight by 25.1%. An even higher dose of trans-2-ene-VPA (400 mg/kg) produced a reduction in maternal body weight during treatment and reduced fetal body weight (by 7.9%), but did not increase resorptions or malformations in the fetuses. On day E18, maternal serum drug concentrations of VPA were higher in the VPA-treated group compared with those of trans-2-ene-VPA in the trans-2-ene-VPA-treated groups at 1 hr posttreatment. At 6 hr posttreatment the reverse was seen. trans-2-ene-VPA may be absorbed more rapidly and distributed differently than VPA. Overall, the data support the view that trans-2-ene-VPA at equal or higher doses than VPA is not teratogenic in rats.

To test the hypothesis that maternal protein deprivation in early pregnancy retards body and organ growth of 63-d (midterm) pig fetuses, 16 primiparous domestic four-way crossbred swine were fed a diet adequate in protein (13% protein) (A) or a protein-restricted (0.7% protein) diet (PR) from d 1 to 63 of pregnancy or to parturition. Maternal body weight, plasma protein, hematocrit, and heart and spleen weights were reduced, and indices of body fatness were increased by the PR diet. Fetal body weights were reduced and fetal placental weights were increased at d 63 by protein restriction. Length from crown to rump and weights of liver, kidney, gastrointestinal tract, and cerebrum were lower in PR than in A fetuses. Concentrations of protein, RNA and DNA in liver, cerebrum and longissimus muscle were unaffected by maternal diet, but total amounts of all three constituents in liver and cerebrum were lower in PR than in A. Relative organ weights were similar in A and PR fetuses except that kidneys and gastrointestinal tract were greater in A fetuses. Newborn body weights and absolute organ weights were generally lower in PR than in A, but relative weights were similar. The observed reduction in body and organ weights and amounts of protein, RNA and DNA in 63-d fetuses and newborn progeny of PR swine establishes that the stunting effect of maternal protein restriction can be initiated by midterm, preceding the period of most rapid accretion of body tissues during prenatal life in the pig.

Insulin may be an important regulator of growth in late fetal life. To assess the importance of endogenous insulin release in regulation of normal fetal growth, eight fetal lamb pairs were given either an intravenous injection of streptozocin (STZ), a nitrosourea that selectively damages pancreatic β-cells, or buffer infusion (controls). In six preparations, twins were used, and in two cases, triplets, thus allowing for comparison between treated and control fetuses residing in the same intrauterine environment. Fetal STZ injection was associated with relative fetal hyperglycemia, hypoinsulinemia, and a decrease in the fetal plasma insulin-glucose ratio. Fetal lambs exposed to STZ also developed a mild nonprogressive metabolic acidosis compared with controls. Fetal body weight was depressed by 21% overall, the magnitude of reduction related to length of time in utero after STZ injection. Similar reductions in organ weights (liver, heart, and kidney) were also observed in STZ-administered fetuses compared with controls. Protein accretion in carcass, liver, and kidney after STZ was also depressed, but no significant changes in fetal lipid accretion were observed. Skeletal growth, as measured by tail and tibial lengths, was also depressed after STZ but to a lesser extent than body weight or protein accretion. Thus, in a stable maternal environment, isolated fetal insulin deficiency is associated with significant retardation of somatic and skeletal growth and protein deposition.

The present study examined the effects of maternal bilateral adrenalectomy and betamethasone treatment on fetal encephalic development, in terms of fetal body weight, brain weight, DNA, protein and lipid contens and morphological development. Both influenced the developmental time patterns of fetal brain and cerebellum. Fetuses of adrenalectomized rats had decreased body weights, whereas brain weight was not affected. Maternal adrenalectomy produces in fetal brain a decreased number of cells and increased cell size, while betamethasone treatment of adrenalectomized rats increased cell number, which was not different from control values; cell size remained lower than in control fetuses. Lipid content was increased in the fetuses of betamethasone-treated rats. In terms of morphological development, laminated structures (hippocampus and brain and cerebellar cortex) were the ones most affected.

In order to evaluate the safety of CH-19 Sweet extract that contains capsinoids, teratology studies were conducted in pregnant Sprague-Dawley rats (20 rats per group) and pregnant New Zealand white rabbits (17 to 22 animals per group). The test substance was administered to rats by gavage for 11 days on gestation days 7 to 17 at doses of 0 (vehicle), 1.25, 2.5, and 5.0 ml/kg and to rabbits for 13 days on gestation days 6 to 18 at doses of 0 (vehicle), 0.25, 0.5, and 1.0 ml/kg. As the concentration of capsinoids in CH-19 Sweet extract was 72.2 to 75.05 mg/ml, the resulting dose of capsinoids administered to rats was 90.25, 180.5, and 361 mg/kg, and to rabbits was 18.76, 37.53, and 75.05 mg/kg in the vehicle, low-, mid-, and high-dose groups, respectively. In the rat study, no deaths occurred in any group and there were no test substance–related changes or abnormalities in clinical signs, body weight, food consumption, or gross pathological findings. There were no test substance–related changes in the number of corpora lutea, number or index of implantations, index of embryofetal deaths, number of live fetuses, sex ratio, fetal body weight at the end of the gestation period, or abnormalities in the placenta of live fetuses. There were no test substance–related abnormalities or variations in the external, skeletal, or visceral examinations of live fetuses. It was concluded that the test article caused neither teratogenic effects nor abnormalities in the progression of ossification. In the rabbit study, there were no test substance–related effects on clinical signs, body weight, food consumption, or necropsy findings. There were neither test substance–related abortions nor test substance–related effects on the number of corpora lutea, or number or index of implantations. There were no test substance–related effects on the number of dead embryos/fetuses, the number of live fetuses, sex ratio, body weight of live fetuses, or gross pathological finding in the placentas. There were no test substance–related external abnormalities or incidences of visceral or skeletal abnormalities or variations, and there were no test substance–related effects on the progress of ossification in any group. The authors concluded the no observed adverse effect level (NOAEL) of CH-19 Sweet extract containing capsinoids on pregnant animals and fetal development/growth was >5.0 ml/kg/day (>361 mg/kg/day as capsinoids) in rats and >1.0 ml/kg/day (>75.05 mg/kg/day as capsinoids) in rabbits.

Chloroacetonitrile (CAN) is a by-product of chlorination of drinking water. Epidemiological studies indicate that it might present a hazard to human health. The present study was designed to investigate the potential adverse effects of intrauterine exposure to CAN on fetal body weight and development of the musculoskeletal system in mice. At gestation day 6, pregnant mice were given CAN (12.5, 25, or 50 mg/kg/day) till gestation day 18. Uteri were then examined and live fetuses were collected, weighed, and evaluated for any malformations. High doses of CAN (50 mg/kg) significantly elevated fetal anomalies and reduced fetal viability. Chloroacetonitrile at a dose of 25 mg/kg did not affect fetal viability and significantly reduced fetal body weight. Subsequent experimentation was performed using this dose level. Histological examination of fetal axial skeleton indicated that CAN resulted in delayed appearance of endochondral ossification centers, widening of the vertebrae, and destruction of the calcified zone. In addition, the skeletal muscle fibers were markedly distorted, were small in size, and were widely separated by connective tissue. Both connective tissue perimysium and endomysium were less cellular compared with control sections. The histological findings were further confirmed by assessing the morphometric changes. Ratios of calcified cartilage to non-calcified cartilage areas in both control and CAN-exposed groups were determined. Also, skeletal muscle fiber diameter of CAN-exposed fetuses was significantly decreased compared with control group. In conclusion, intrauterine exposure to low levels of CAN decreases fetal body weight and induces malformations in the musculoskeletal system in mice.

Aim: The aim of the present study was to determine whether fasting during Ramadan causes ketonemia and/or ketonuria and their effects on fetal intrauterine development. Methods: Thirty-six consecutive healthy women with uncomplicated pregnancies of ≥20 weeks of gestation who were fasting during Ramadan were included in the study group (group 1). The control group (group 2) consisted of 29 healthy pregnant women who were not fasting. Doppler ultrasonography was performed in all subjects in the beginning and at the end of Ramadan to evaluate the changes in the following measurements: fetal biparietal diameter; fetal femur length; and estimated fetal body weight. Fetal biophysical profile, amniotic fluid index, and umbilical artery systole/diastole ratio were measured in the beginning and at the end of Ramadan. Effects of fasting on the mother were evaluated by measuring serum concentrations of 3s hydroxybutyrate and glucose, and urinary concentration of ketone. Subjects with any of the followings were excluded: diabetes; thyroid dysfunction; Cushing's syndrome; adrenal disease; pre-eclampsia; and multiple pregnancy. Results: The mean duration of fasting in the study group was 18 ± 2.1 days. The mean maternal glucose level was significantly lower in the study group than in the control group (P = 0.003). No statistically significant differences were found between the two groups in the comparisons of other parameters. Conclusion: We concluded that fasting during Ramadan does not lead to maternal ketonemia or ketonuria in pregnant women. In addition, fasting during Ramadan has no significant adverse effect on intrauterine fetal development or the fetus's health.

1. Four pregnant ewes were operated on at 121-126 days of gestation. An electromagnetic flow sensor and an inflatable occluder were placed on the maternal common internal iliac artery. The ovarian arteries and veins were ligated. Indwelling catheters were placed in a maternal femoral artery and uterine vein and in the amniotic and allantoic fluids. An inflatable occluder was placed around the umbilical cord, close to the fetal abdomen. 2. Eight to nine days after surgery, the cord was occluded, the fetus killed and uterine blood flow reduced to one-quarter of its control value. The rate of water loss from the uterine circulation was calculated from blood flow and the venoarterial difference in blood osmolality. The amniotic and allantoic fluids were made hypertonic by infusion of 2 l into each sac of a solution of 1.5 mol of mannitol per litre of saline. The rate of water loss from the maternal uterine circulation was then measured five times over the next 4.5 h. 3. The combined filtration coefficient surface area product of the interfaces between maternal blood and the amniotic and allantoic sacs, normalized per kilogram fetal body weight, was (2.8 +/- 0.5) x 10(-6) cm3 s-1 kPa-1 kg-1 (mean +/- S.E.M).

Diminazene diaceturate was dissolved in deionized water and administered to pregnant rats by oral gavage once daily on days 8–15 of pregnancy at dose levels of 0, 100, 250, 500 and 1000 mg/kg. On day 21 of pregnancy, the dams were killed and the number of implants, resorptions and live fetuses counted. All fetuses were examined by routine teratological method. A significant increase in fetal resorptions and decrease in fetal body weights were found at the 1000 mg/kg dose. No significant increase in the incidence of anomalous fetuses was observed in external, skeletal and internal examinations even at the maternally toxic dose of 1000 mg/kg. Thus, these data indicate that diminazene diaceturate is not teratogenic in rats.

meso-2,3-Dimercaptosuccinic acid (DMSA), an effective antagonist for the treatment of lead, arsenic, mercury, and cadmium poisoning, was evaluated for developmental toxicity in pregnant Sprague-Dawley rats. DMSA was administered by gavage on d 6-15 of gestation at doses of 0, 100, 300, or 1000 mg DMSA/kg/d. At termination on d 20 of gestation, fetuses were examined for external, visceral, and skeletal malformations and variations. Maternal toxicity was observed at all doses, as evidenced by a significant decrease in body weight gain. There were no effects with respect to hematology or clinical chemistry. Increased early resorptions, increased percentage postimplantation loss, and reduced fetal body weight per litter were observed at 100, 300, and 1000 mg/kg/d. Examination of fetuses for gross external abnormalities, visceral and skeletal malformations, or ossification variations revealed that DMSA did not produce teratogenicity at any dosage level. However, significant fetotoxicity was observed at 100, 300, and 1000 mg/kg/d. The no-observable-effect level (NOEL) for maternal and developmental toxicity was less than 100 mg DMSA/kg/d.

A series of studies to further evaluate the developmental and reproductive toxicity of inhaled 1,3-butadiene was sponsored by the National Toxicology Program. Pregnant Sprague-Dawley rats (24-28/group) and Swiss (CD-1) mice (18-22/group) were exposed to atmospheric concentrations of 0, 40, 200, or 1000 ppm 1,3-butadiene for 6 hr/day on days 6 through 15 of gestation (dg) and killed on dg 18 (mice) or dg 20 (rats). Subsequently, the uterine contents were evaluated; individual fetal body weights were recorded; and external, visceral, and skeletal examinations were performed. In rats, maternal toxicity was observed in the 1000-ppm group in the form of reduced extragestational weight gain and, during the first week of treatment, decreased body weight gain. Under these conditions, there was no evidence of developmental toxicity in rats. In contrast, results of the mouse developmental toxicity study indicated that the fetus may be more susceptible than the dam to inhaled 1,3-butadiene. Maternal toxicity was observed in mice at the 200- and 1000-ppm 1,3-butadiene exposure levels, whereas 40 ppm and higher concentrations of 1,3-butadiene caused significant exposure-related reductions in the mean body weights of male fetuses. Mean body weights of female fetuses were also reduced at the 200- and 1000-ppm exposure levels. No increased incidence of malformations was observed in either study. Other studies addressing male reproductive and mutagenesis end points were performed with B6C3F1 mice (sperm-head morphology) and Swiss (CD-1) mice (dominant lethal study).(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant murine interferon-γ (Rec-MuIFN-γ) was administered intramuscularly to C3H HeNCrj mice on Days 6–15 of gestation at dosage levels of 8 × 105, 4 × 106, and 2 × 107 u/kg/day. Dams were killed for examination of fetuses on Day 18 of gestation. Pregnant females that received 2 × 107 u/kg/day of Rec-MuIFN-γ showed uterine bleeding on Days 10–15 of gestation and could not maintain their pregnancy. These dams died on Days 13–17 or were killed in extremis on Days 10–15 for examination, and therefore no fetal data were available for this group. In the 2 × 107 u/kg/day group, the mean absolute weights of the lung and spleen increased and the mean absolute weight of the liver, red blood cells (RBC), hematocrit, and hemoglobin decreased significantly. Surviving dams in the 8 × 105 and 4 × 106 u/kg/day groups showed significant increases in the mean absolute weights of the lung, liver, kidneys, and spleen and a decrease in platelet count. Significant increases in the weights of the heart and ovaries and decreases in RBC, hematocrit, and hemoglobin were observed in the 4 × 106 u/kg/day group. Histopathological examination revealed increased extramedullary hematopoiesis in the spleen of the 4 × 106 and 2 × 107 u/kg/day groups. Fetuses showed no external, visceral, or skeletal malformations and variations caused by the administration of Rec-MuIFN-γ in any of the treated groups. Although a slight but statistically significant decrease in fetal body weight and a delay in ossification were seen in fetuses in the 4 × 106 u/kg/day group, these findings were considered to be the result of maternal toxicity and not fetal toxicity. No fetal effects were observed in the 8 × 105 u/kg/day group.

The effects of dietary supplementation with sodium selenite (3.0 or 4.5 ppm Se) for 8 weeks prior to and throughout gestation on sodium salicylate induced embryo- and fetotoxicity (resorptions, fetal deaths, malformations, fetal weight reduction) have been studied in the rat. Salicylate was administered either as daily intragastric bolus doses of 250 mg/kg on gestation days 6-13 (maternal peak and trough salicylate levels of 222-120 micrograms/ml whole-blood) or via constant rate intravenous infusion of 150 mg/kg/day on the same gestation days via implanted osmotic minipumps (stable average maternal blood salicylate level of 120 micrograms/ml = human antirheumatic concentration). Both gavage and infusion of salicylate resulted in an increase of resorptions and fetal deaths as well as a decrease of fetal body weights. Gavage with salicylate also produced about 50% malformed fetuses. Selenite did not protect against the embryotoxic effects of salicylate administered as intragastric bolus doses. However, selenite was found to significantly increase fetal survival rate in the infusion experiment, although it did not counteract the decrease of fetal body weight. In animals fed selenite only, no negative effects on fetal body development were noted. The protective effect of selenite against salicylate induced embryotoxicity is difficult to explain, since very little is known about the mechanisms of salicylate embryotoxicity and the biological effects of selenium. However, an interaction between selenium, via glutathione peroxidase, and salicylate at the level of prostaglandin synthesis could be possible.

2-Methoxyethanol (2-ME) was applied as a single dermal dose on the backs of collared, pregnant Sprague-Dawley rats on Gestation Days (GD) 10, 11, 12, 13, or 14 at doses of 0 and 2000 mg/kg, and at doses of 0, 250, 500, and 1000 mg/kg on GD 12. Except for a transient loss in body weight observed the day after 2-ME administration, no signs of maternal toxicity were observed. On GD 20, dams were necropsied and the fetuses evaluated for normal development. Resorptions were significantly (p less than 0.05) increased in dams exposed to 2-ME on GD 10. Fetal body weights were reduced at dose levels of 1000 and 2000 mg/kg, but statistically significant differences were found only on GD 10 and 12. Significant increases in external, visceral, and skeletal malformations were observed in fetuses exposed to 2-ME at dose levels of 500 mg/kg or greater. Defects of the cardiovascular and urinary systems were the prominent visceral malformations observed. Limb defects (especially those pertaining to the digits) and vertebral column defects (primarily of the tail) were the most frequently observed skeletal defects. At the 2000 mg/kg dose level, 2-ME was teratogenic regardless of the GD of administration. Based on the results of this study, the no observed adverse effect level for developmental toxicity for a single dermal dose of 2-ME applied on GD 12 was determined to be 250 mg/kg.

The teratogenicity of tri-n-butyltin chloride (TBTC1) was examined in Wistar rats. The pregnant rats were administered orally 25, 15, 9, 5 and 0(Control) mg of TBTC1/kg of body weight/day from day 7 to 15 of pregnancy. Maternal toxicity, as evidenced by both of decreased body weight gain and food consumption was observed at 25, 15 and 9 mg/kg/day dose group. However, only in the 25 mg/kg/day dose group some clinical signs of toxicity (sedation, diarrhoea and salivation) were observed and 70 percent of the dams were dead. In the 25 mg/kg/day dose group, all fetuses were dead. Statistically significant reductions in the female fetal body weight were observed in 9 and 5 mg/kg/day dose groups. In all groups treated with TBTC1 except the 25 mg/kg/day dose group, no significant differences in the numbers of live fetuses and intrauterine death (dead fetuses and resorptions) or sex ratios of fetuses were found between the TBTC1-treated and control groups. Fetal external, skeletal and internal malformations were not observed at any of the dose levels. However, several types of skeletal and internal variations including delayed ossifications were observed in some groups treated with TBTC1, but the incidences were not significantly different from controls. Also, two fetuses with dilatation of the renal pelvis were found in 9 and 5 mg/kg/day dose group. Statistically significant increases of placental weight in all TBTC1-treated groups were observed when compared to that of control group. In conclusion, TBTC1 administered orally to Wistar rats during days 7-15 of pregnancy produced related signs of fetal toxicity but no evidence of teratogenicity and induced a marked increase in placental weight.

The growth of the adrenal gland was studied in 60 brazilian fetuses (12-37 weeks post-conception). The right adrenal gland was quantitatively evaluated; its weight, length and thickness were correlated to the fetal body weight, to the Crown-Pump length and to the gestational age by the allometric method (LogY = kLogX + LogB). The width was the only linear measure with positive allometry, and was the one which presented the greatest relative growth, while the thickness had the smallest one. The adrenal weight presented positive allometry relating to the Crown-Rump length (k = 2.32) and to the gestational age (k = 2.40). The importance of these knowledges in the precocious ultrasonographic diagnosis of congenital adrenal pathologies is discussed.

Pregnant hamsters were treated with selenite, selenate, and selenomethionine during the critical stages of embryogenesis. The dosing regimens were oral, intravenous, and osmotic minipump infusion. Malformations, mainly encephaloceles, were noted with oral and intravenous selenite and selenate but were associated with maternal toxicity manifested by inanition and weight loss. Fetal body weights and lengths were reduced in a dose-dependent manner with the inorganic forms. Single oral doses of selenomethionine above 77 μmol/kg induced similar malformations but not when the dose was delivered orally over four days nor by minipump over several days. Fetal body weights and lengths were decreased by selenomethionine in a dose-dependent manner. Maternal toxicity was pronounced with the higher doses of selenomethionine. Assigning a specific teratogenic effect to selenium is confounded by maternal toxicit.

The potential of oral exposure to dolomite, a natural product that contains calcium and magnesium, to initiate teratogenesis was analyzed in Wistar rats. Animals received dolomite oral dosages of 500 and 1500mg/kg during the period of gestation from day 6-15 post conceptionem (p.c.). Maternal, embryo and fetal toxicity were evaluated. Dolomite exposure did not produce maternal toxicity assessed by clinical observations, body weight gain, hematology parameters and relative organs weight. Signs of embryo-fetal toxicity were not observed. Skeletal malformations and visceral variations were similar in control and dolomite-treated groups. On the other hand, slight increase was observed in fetal body weight in the dolomite-treated group. Treatment with dolomite resulted in significantly decreased incidences of unossified xiphisternum, incomplete ossification of xiphisternum and sternebrae. These effects could be caused by a beneficial influence of calcium and magnesium salts present in dolomite on ossification process. In conclusion, in this study we found that the oral exposure to rats of up to 1500mg/kg of dolomite during organogenesis did not induce significant maternal and embryo-fetal toxicity.

Objective This study was undertaken to investigate whether maternal growth hormone supplementation in pregnant sheep could reverse intrauterine growth restriction (IUGR) induced by placental embolization. Study Design Animals were randomized into control, intrauterine growth restriction + saline or intrauterine growth restriction + growth hormone (twice daily injections of 0.1 mg/kg growth hormone) groups. Intrauterine growth restriction was induced by twice daily placental embolization between 93 and 99 days' gestation, and treatment was from 100-128 days' gestation (term = 147 days' gestation). Results Embolization reduced fetal growth rate and body weight but increased brain-to-liver weight ratio. Growth hormone treatment significantly increased fetal growth rates and fat deposition, and improved fetal body weight and length, but not liver weight. Growth hormone treatment produced hydranencephalic brain lesions in some fetuses. Conclusion Maternal growth hormone treatment partially reversed intrauterine growth restriction caused by placental insufficiency. However, the possible connection between growth hormone treatment and fetal brain injury requires further investigation

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. Keywords:: Tokishakuyakusan, Nω-nitro-L-arginine methyl ester (L-NAME), pre-eclampsia, intrauterine growth retardation (IUGR), somatotrope

Prenatal stress is known to affect the development of the brain, and exaggerate the developmental toxicity of chemicals. Many studies of developmental neurotoxicity (DNT) use pregnant rodents mated at the supplier, which consequently suffer from the stress of shipping and of environmental changes. Here, we demonstrated differences in the developmental neurotoxicity induced by valproate (VPA) between pregnant rats mated at our own animal facility (in-house group) and rats purchased pregnant (supplier group). Rats were treated with VPA (800mg/kg) orally on gestation day (GD) 9 or 11 (VPAE9 or VPAE11), and the fetal brain was examined at embryonic day 14 using immunohistochemistry for TuJ1 (a marker for immature neurons). The size of the fetal brain was also measured. The treatment decreased fetal live viability and fetal body weight only in the supplier group. VPA treatment on either day impaired the development of TuJ1-positive neurons in the cerebral cortex. The size of the forebrain was also affected by VPA. The supplier group was much more sensitive to these toxic effects. Therefore, difference in mating place (one's own animal facility or supplier) takes part in reproducibility of valproate-induced DNT.

Studies in ovine fetus and placenta have pointed to an interaction between the fetal liver and the placenta. The supply of amino acids and carbohydrates depends on this interaction. These studies have led to clinical studies in normal and high-risk pregnancies. The objective of the present review was to compare changes in fetal circulation, in terms of both velocimetry and actual blood flow measurements, and to couple such data with data on the placental transport of amino acids. Flow studies were carried out on the umbilical vein with measurements of time-averaged velocity and venous diameter. A similar approach was used for measurements of ductus venosus flow. Stable-isotope-labeled amino acids were used to study placental transport by the non-steady state approach. The studies of flow showed a marked reduction in umbilical blood flow even when expressed per kilogram fetal body weight in fetal-growth-restricted pregnancies. This may be coupled with an increased ductus venosus shunt, the combination leading to a marked reduction in fetal hepatic blood flow. The placental transport of some amino acids is reduced in fetal-growth-restricted pregnancies. Furthermore, nonglucose carbohydrates and polyols are found in fetal blood, some in concentrations higher than maternal concentrations. There is significant uptake of several polyols and of mannose across the umbilical circulation in normal pregnancies. In conclusion, both perfusion and permeability can now be studied in both normal and high-risk pregnancies.

In the current study, we examined the effects of Cd on Cd, Cu, Zn and Fe levels in placenta and maternal and fetal plasma and tissues, the placental weight, total fetal and maternal body weights, and fetal and maternal tissue weights during pregnancy. A total of 21 adult female rats were treated during gestation with drinking water containing one of the following: 70 mg/L of CdCl2, a combination of 70 mg/L of CdCl2 and 70 mg/L of CuSO4, or no addition (control). Placenta Cu and Fe levels, fetal liver and kidney Cu levels, and fetal liver tissue weights were lower in the group administered Cd than in the control group. Also, Cd levels in the placenta, maternal and fetal liver, and maternal kidney were higher in the group treated with Cd than in controls. In the group administered both Cd and Cu, fetal body and tissue weights did not change, but Cd levels in the placenta, maternal and fetal liver, and maternal kidneys were higher than in controls. Zn and Fe levels in the maternal kidney and fetal liver were also lower in this group. Cd exposure during pregnancy resulted in Cd accumulation in maternal and fetal tissues during pregnancy and a decrease in the total weight of fetuses, and the combination of Cd and Cu caused some changes in the both maternal and fetal levels of Cu, Zn, and Fe, but it did not cause changes in the total fetal body weight or the weights of individual tissues.

Environmental influences such as nutritional restriction during early gestation in cattle may impair fetal development and compromise functions in adulthood. During the first trimester of gestation fetal gonads are formed. We hypothesised that either restriction or excess of nutrients ingested by cows during the first third of pregnancy interferes with fetal body weight (BW) and ovary development. Twenty-one uniparous Nelore cows (BW = 488 ± 24 kg, body condition score, BCS = 3.1 ± 0.1) were subjected to timed AI with sexed semen (female) of a single bull and individually allocated to different diets. The diet of the control group (C) met the maintenance requirements, and the groups of high (A) and low (B) were either 180% or 60% of maintenance respectively. Live weight and BCS were assessed weekly to adjust the diet according to the individual weight of each animal. At 60 days of gestation, 9 fetuses (3/group) were removed by colpotomy (accessed through vagina), weighed, and their ovaries were dissected and weighed. One fetal ovary (of each pair) was analysed by RNA-seq (mRNA). The effects of treatments on both ovarian and fetal weight were compared by ANOVA (proc GLM, SAS 9.3, SAS Institute Inc., Cary, NC, USA). During the 60 days of treatment, cows from Group A gained 66 kg (from 474 ± 6 kg to 541 ± 10 kg) and 1.25 points in BCS (from 3.0 to 4.25), whereas the cows in group B lost 61 kg (from 458 ± 3 kg to 397 ± 6 kg) and 1 point in BCS (from 3.2 to 2.2). Fetal ovary weight (sum of the two) was lower in group B (0.007 ± 0.001 g; P 0.08) between each other. Fetuses in group B weighed less (12.8 ± 1.14 g; P

Objectives In preeclampsia (PE) an imbalance in the T helper 1 (Th1)/T helper 2 (Th2) cytokine balance has been proposed with a deviation toward the Th1 cytokine profile rather than a shift toward Th2 cell differentiation in normal pregnancy, while its reason has been not yet known. Recently, many reports from western countries and our reports in Japan have been concerned with the relationship between female fetus and PE. But, this mechanism of female preponderance in PE has not been defined. Methods After Institutional Review Board approval, we examined the effect of maternal status (age and body mass index [BMI]), fetal sex, fetal body weight, and placental weight on maternal Th1/Th2 cytokine balance in singleton cases of PE in Japan. The ratio of IFN γ /IL-4 in peripheral blood CD4+ T cells was determined using a flow cytometry in 62 PE patients sampled after the onset of PE. Analysis of covariance (ANCOVA) was used to investigate the relationship between feto-maternal conditions and maternal Th1/Th2 cytokine balance. Results The Th1/Th2 ratio was higher in mothers with higher BMI and a male fetus, as well as in mothers with lower BMI and a female fetus. Fetal sex had a significantly different effect on the relationship between Th1/Th2 ratio and BMI (P = 0.04). But fetal sex didn’t affect the Th1/Th2 ratio in relation to maternal age, fetal weight, and placental weight (P = 0.95, P = 0.83, P = 0.93, respectively). Conclusions The current study suggest that high-BMI women with a male fetus and low-BMI women with a female fetus tend to develop PE with Th1 cytokine predominance. These findings may help clarify the previous conflicting results about fetal sex as one of risk factors in the pathogenesis of PE. Disclosures A. Shiozaki: None. S. Suzuki: None. K. Naruse: None. S. Soeda: None. Y. Ono: None. A. Sameshima: None. N. Yoneda: None. M. Ito: None. S. Yoneda: None. H. Kobayashi: None. S. Saito: None.

Dietary exposures to food pollutants such as mycotoxin(s) or pesticide(s) are most significant due to their adverse effects on the production and reproduction in animals and the human population. The present investigation was conducted to evaluate the teratogenic potential of citrinin (CIT) and endosulfan either alone or in combination in pregnant rats during gestational days 6–20. Endosulfan (1 mg kg−1 body weight, by oral intubation) and CIT (10 mg kg−1 feed, through diet) when administered either alone or in combination in pregnant rats caused significant teratogenic effects in the developing fetuses. There was no maternal mortality, however, reduced maternal weight gain and number of live fetuses and increased fetal resorptions were recorded in all the treated groups. The fetal body weights and crown to rump lengths were significantly decreased and the per cent gross, visceral and skeletal anomalies were significantly increased in the fetuses of dams of all the treated groups. The internal hydrocephalus, cerebellar hypoplasia, microphthalmia, contracted and notched kidneys, multilobulated liver, dilated renal pelvis, incomplete ossification of skull bones, rib anomalies and sacral and caudal vertebrae agenesis were the important fetal malformations. The occurrence of fetal gross, skeletal and visceral malformations was more severe in the combination group, suggesting an additive interaction of CIT and endosulfan in inducing developmental toxicity in Wistar rats. Copyright © 2006 John Wiley & Sons, Ltd.

The potential for trichloroethylene (TCE) and perchloroethylene (PERC) to induce developmental toxicity was investigated in Crl:CD (SD) rats whole-body exposed to target concentrations of 0, 50, 150 or 600 ppm TCE or 0, 75, 250 or 600 ppm PERC for six hours/day, seven days/week on gestation day (GD) 6-20 and 6-19, respectively. Actual chamber concentrations were essentially identical to target with the exception of the low PERC exposure level, which was 65 ppm. The highest exposure levels exceeded the limit concentration (2 mg/L) specified in the applicable test guidelines. Maternal necropsies were performed the day following the last exposure. Dams exposed to 600 ppm TCE exhibited maternal toxicity, as evidenced by decreased body weight gain (22% less than control) during GD 6-9. There were no maternal effects at 50 or 150 ppm TCE and no indications of developmental toxicity (including heart defects or other terata) at any exposure level tested. Therefore, the TCE NOEC for maternal toxicity was 150 ppm, whereas the embryo/fetal NOEC was 600 ppm. Maternal responses to PERC were limited to slight, but statistically significant reductions in body weight gain and feed consumption during the first 3 days of exposure to 600 ppm, resulting in a maternal NOEC of 250 ppm. Developmental effects at 600 ppm consisted of reduced gravid uterus, placental and fetal body weights, and decreased ossification of thoracic vertebral centra. Developmental effects at 250 ppm were of minimal toxicological significance, being limited to minor decreases in fetal and placental weight. There were no developmental effects at 65 ppm.