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Background: Fetal alcohol syndrome (FAS) is a leading cause of neurodevelopmental impairments (NDIs) in developed countries. Sensory deficits can play a major role in NDI, yet few studies have investigated the effects of prenatal alcohol exposure on sensory function. In addition, there is a paucity of information on the lifelong effects of prenatal alcohol exposure. Thus, we sought to investigate the effects of prenatal alcohol exposure on auditory function across the life span in an animal model. Based on prior findings with prenatal alcohol exposure and other forms of adverse prenatal environments, we hypothesized that animals prenatally exposed to alcohol would show an age-dependent pattern of (i) hearing and neurological abnormalities as postweanling pups, (ii) a substantial dissipation of such abnormalities in young adulthood, and (iii) a resurgence of such abnormalities in middle-aged adulthood. Methods: Pregnant rats were randomly assigned to an untreated control (CON), a pair-fed control (PFC), or an alcohol-treated (ALC) group. The ALC dams were gavaged with 6 mg/kg alcohol daily from gestation day (GD) 6 to 21. The PFC dams were gavaged daily from GD6 to GD21 with an isocaloric and isovolumetric water-based solution of maltose-dextrins and pair-fed to the ALC dams. The CON dams were the untreated group to which the ALC and CON groups were compared. Hearing and neurological functions in the offspring were assessed with the auditory brainstem response (ABR) at the postnatal ages of 22, 220, and 520 days. Results: In accord with our hypothesis, ABR abnormalities were first observed in the postweanling pups, largely dissipated in young adulthood, and then resurged in middle-aged adulthood. This age-related pattern suggests that the ALC pups had a developmental delay that dissipated in young adulthood and an enhanced age-related deterioration that occurred in middle-aged adulthood. Such a pattern is consistent with the fetal programming hypothesis of adult-onset diseases (the Barker hypothesis). Conclusions: Our findings have important clinical implications for the assessment and management of (i) childhood hearing disorders and their comorbidities (i.e., speech-and-language, learning, and attention deficit disorders) and (ii) enhanced age-related hearing and neurological degeneration in middle-aged adulthood that can result from prenatal alcohol exposure. We recommend hearing evaluation be a part of any long-term follow-up for FAS patients and patients exposed to any adverse prenatal environment.

Consuming omega-3 fatty acids (omega-3 FA) during pregnancy and lactation is beneficial to fetal and infant development and might reduce the incidence and severity of preterm births by prolonging pregnancy. Consequently, supplementing maternal diets with large amounts of omega-3 FA is gaining acceptance. However, both over- and under-supplementation with omega-3 FA can harm offspring development. Adverse fetal and neonatal conditions in general can enhance age-related neural degeneration, shorten life span and cause other adult-onset disorders. We hypothesized that maternal over- and under-nutrition with omega-3 FA would shorten the offspring's life span and enhance neural degeneration in old adulthood. To test these hypotheses, female Wistar rats were randomly assigned to one of the three diet conditions starting from day 1 of pregnancy through the entire period of pregnancy and lactation. The three diets were Control omega-3 FA (omega-3/omega-6 ratio approximately 0.14), Excess omega-3 FA (omega-3/omega-6 ratio approximately 14.5) and Deficient omega-3 FA (omega-3/omega-6 ratio approximately 0% ratio). When possible, one male and female offspring from each litter were assessed for life span and sensory/neural degeneration (n=15 litters/group). The Excess offspring had shorter life spans compared to their Control and Deficient cohorts (mean+/-SEM=506+/-24, 601+/-14 and 585+/-21 days, p

Galectin-1 is an anti-inflammatory lectin with pleiotropic regulatory functions at the crossroads of innate and adaptive immunity. It is expressed in immune privileged sites and is implicated in establishing maternal–fetal immune tolerance, which is essential for successful pregnancy in eutherian mammals. Here, we show conserved placental localization of galectin-1 in primates and its predominant expression in maternal decidua. Phylogenetic footprinting and shadowing unveil conserved cis motifs, including an estrogen responsive element in the 5′ promoter of LGALS1 , that were gained during the emergence of placental mammals and could account for sex steroid regulation of LGALS1 expression, thus providing additional evidence for the role of galectin-1 in immune–endocrine cross-talk. Maximum parsimony and maximum likelihood analyses of 27 publicly available vertebrate and seven newly sequenced primate LGALS1 coding sequences reveal that intense purifying selection has been acting on residues in the carbohydrate recognition domain and dimerization interface that are involved in immune functions. Parsimony- and codon model-based phylogenetic analysis of coding sequences show that amino acid replacements occurred in early mammalian evolution on key residues, including gain of cysteines, which regulate immune functions by redox status-mediated conformational changes that disable sugar binding and dimerization, and that the acquired immunoregulatory functions of galectin-1 then became highly conserved in eutherian lineages, suggesting the emergence of hormonal and redox regulation of galectin-1 in placental mammals may be implicated in maternal–fetal immune tolerance.

Problem Galectin-1 can regulate immune responses upon infection and inflammation. We determined galectin-1 expression in the chorioamniotic membranes and its changes during histological chorioamnionitis. Method of study Chorioamniotic membranes were obtained from women with normal pregnancy (n = 5) and from patients with pre-term pre-labor rupture of the membranes (PPROM) with (n = 8) and without histological chorioamnionitis (n = 8). Galectin-1 mRNA and protein were localized by in situ hybridization and immunohistochemistry. Galectin-1 mRNA expression was also determined by quantitative reverse transcriptase polymerase chain reaction. Results Galectin-1 mRNA and protein were detected in the amniotic epithelium, chorioamniotic fibroblasts/myofibroblasts and macrophages, chorionic trophoblasts, and decidual stromal cells. In patients with PPROM, galectin-1 mRNA expression in the fetal membranes was higher (2.07-fold, P = 0.002) in those with chorioamnionitis than in those without. Moreover, chorioamionitis was associated with a strong galectin-1 immunostaining in amniotic epithelium, chorioamniotic mesodermal cells, and apoptotic bodies. Conclusion Chorioamnionitis is associated with an increased galectin-1 mRNA expression and strong immunoreactivity of the chorioamniotic membranes; thus, galectin-1 may be involved in the regulation of the inflammatory responses to chorioamniotic infection.

Omega-3 fatty acids (omega-3 FA) consumption during pregnancy and lactation is beneficial to fetal and infant growth and may reduce the severity of preterm births. Thus, scientists and clinicians are recommending increasingly higher omega-3 FA doses for pregnant women and nursing babies for advancing the health of preterm, low birth weight, and normal babies. In contrast, some studies report that over-supplementation with omega-3 FA can have adverse effects on fetal and infant development by causing a form of nutritional toxicity. Our goal was to assess the effects of omega-3 FA excess and deficiency during pregnancy and lactation on the offspring's neural transmission as evidenced by their auditory brainstem responses (ABR). Female Wistar rats were given one of three diets from day 1 of pregnancy through lactation. The three diets were the Control omega-3 FA condition (omega-3/omega-6 ratio approximately 0.14), the Deficient omega-3 FA condition (omega-3/omega-6 ratio approximately 0%) and the Excess omega-3 FA condition (omega-3/omega-6 ratio approximately 14.0). The Control diet contained 7% soybean oil, whereas the Deficient diet contained 7% safflower oil and the Excess diet contained 7% fish oil. The offspring were ABR-tested on postnatal day 24. The rat pups in the Excess group had prolonged ABR latencies in comparison to the Control group, indicating slowed neural transmission times. The pups in the Excess group also showed postnatal growth restriction. The Deficient group showed adverse effects that were milder than those seen in the Excess group. Milk fatty acid profiles reflected the fatty acid profiles of the maternal diets. In conclusion, excess or deficient amounts of omega-3 FA during pregnancy and lactation adversely affected the offspring's neural transmission times and postnatal thriving. Consuming either large or inadequate amounts of omega-3 FA during pregnancy and lactation seems inadvisable because of the potential for adverse effects on infant development.

Consumption of the nutrients omega-3 fatty acids (omega-3 FA) during pregnancy and lactation is considered beneficial to fetal and infant development. It may also reduce the incidence and severity of preterm births by prolonging gestational length. However several recent human and animal studies have reported that over-supplementation with omega-3 FA, especially in the form of fish oil, can have adverse effects on fetal and infant development and the auditory brainstem response (ABR). Our goal was to assess further the effects of omega-3 FA excess and deficiency during pregnancy and lactation on the offspring's auditory acuity as evidenced by their ABR thresholds. Female Wistar rats were given diets that were either deficient, adequate (control) or excess in omega-3 FA from day 1 of pregnancy through lactation. The offspring were ABR-tested at the postnatal age of 24 days. The rat pups in the Excess treatment condition had significantly elevated (worse) ABR thresholds, postnatal growth restriction, and a trend for increased postnatal mortality in comparison to the Control group. The Deficient group was intermediate. In conclusion, excess or deficient amounts of omega-3 FA during pregnancy and lactation in the laboratory rat adversely affected the offspring's auditory acuity. Postnatal thriving was also adversely affected. Consuming or administering large or inadequate amounts of omega-3 FA during pregnancy and lactation seems inadvisable because of the potential for adverse effects on infant development.

Objective The purpose of this study was to examine the effects of prolonged in utero meconium exposure on adult learning and memory, as measured by the Morris water maze. Study design Timed pregnant Long-Evans rats were studied. On gestational day 20 (term, 21 days of gestation), laparotomy was performed, and each maternal animal received an injection of clear amniotic fluid or meconium-stained amniotic fluid into each gestational sac. The laparotomy incision was closed, and the animals received postoperative monitoring through delivery. On postnatal days 145 to 148, the offspring underwent Morris water maze testing. The mean (±SEM) for the latency time was reported for each day's trial and compared between groups. Results There were significant differences between meconium-stained amniotic fluid group and clear amniotic fluid group in the mean time to platform on day 1 (82.7 ± 1.8 seconds vs 75.9 ± 3.0 seconds; P =.04), day 2 (60.5 ± 3.5 seconds vs 47. 8 ± 4.6 seconds; P =.03), and day 3 (56.5 ± 4.5 seconds vs 34.7 ± 4.4 seconds; P =.001). However, there were no differences on days 4 and 5. There were also no differences between recall and response learning trials that were done after a 12-day retention period. Conclusion In the absence of hypoxia or infection, prolonged in utero meconium exposure is associated with a delay of spatial learning in the adult rat.

The purpose of this study was to determine the effect of pregnancy on serum concentrations of estradiol, progesterone and prolactin in Long-Evans rats. Female Long-Evans rats, both pregnant and non-pregnant, were used. Four groups (n = 10 rats in each group) were studied: Non-pregnant rats; pregnant rats at 7, 14, and 20 gestational days. Maternal blood was collected transcardially, and serum estradiol, progesterone, and prolactin were measured by radioimmunoassay. Commercial kits from Diagnostic Products Corporation for estradiol and progesterone, and an established in-house double antibody assay for prolactin, were utilized. Statistical analysis was performed using ANOVA, followed by Newman-Keuls post hoc test when applicable. Estradiol concentrations were increased throughout gestation from 16.2 ± 6.2 pg/mL (mean ± SD) in the non-pregnant rat to 23.2 ± 8.8, 25.0 ± 7.7, and 30.3 ± 29.6 pg/mL on gestational days 7, 14, and 20, respectively. Progesterone showed the same trend, increasing from 7.2...

Our purpose was to determine whether maternal rat seizure activity was associated with fetal histopathologic brain changes and whether magnesium sulfate reduced these changes.Electrodes were stereotaxically implanted into the hippocampus of nonpregnant rats 1 week before breeding. Pregnant rats were randomly assigned to 1 of 4 groups: (1) sodium chloride solution and no seizure (n = 2), (2) magnesium sulfate and no seizure (n = 2), (3) sodium chloride solution and seizure (n = 5), and (4) magnesium sulfate and seizure (n = 5). On gestational days 9, 11, 13, 15, 17, and 19, subcutaneous doses of sodium chloride solution or magnesium sulfate were administered to all rats every 20 minutes for 4 hours (loading-maintenance-loading), followed by seizure induction. On gestational day 20, the rats were perfused with formalin and fetuses were delivered via cesarean. Fetuses were perfused with formalin, brains were obtained and embedded in paraffin, and the forebrain and hindbrain were sectioned in the coronal plane and stained with hematoxylin and eosin. A neuropathologist masked to the protocol performed histopathologic grading of each section, including extent and nature of cellular damage. Eleven brain regions were examined in each section. Scores were expressed as mean +/- SD. Kruskal-Wallis analysis of variance was used, and P.05 was considered significant.We evaluated 26 fetal brains in group 1, 9 in group 2, 72 in group 3, and 45 in group 4. Fetuses in the sodium chloride solution-and-seizure group (group 3) presented significantly higher grades of neuronal damage in the hippocampus (group 1, 0.50 +/- 0. 88; group 2, 0.22 +/- 0.66; group 3, 1.01 +/- 1.17; and group 4, 0. 48 +/- 0.72) and in the tegmentum region (group 1, 1.0 +/- 1.0; group 2, 0.8 +/- 1.0; group 3, 1.7 +/- 0.7; and group 4, 1.5 +/- 0. 8) (P.05, group 3 compared with others). Isolated and patchy neuronal injury with shrinkage of cells, nuclear pyknosis, and karyorrhexis were the main histologic findings.Maternal rat seizure activity was associated with histologic brain injury in the fetus. Maternal administration of magnesium sulfate before seizure prevented or significantly decreased this effect.

To determine whether transient acute maternal hypoxemia during the end of pregnancy may cause neuronal damage in fetal rat brains.Nine pregnant rats (4 study and 5 controls) at 16-17 gestational days were studied. The study rats were placed in a chamber and breathed a gas mixture of 11.8% oxygen, 4.95% CO2, and nitrogen for either 1 or 2 h, while the control animals breathed room air. Tail venous blood was collected and gases were evaluated at the beginning and conclusion of the exposure periods. After 72 h of recovery, at 19-20 days' gestation, the fetal cardiovascular systems were perfused with saline and formalin. The brains were embedded in paraffin, sectioned in coronal plane, and stained with hematoxylin and eosin Histologic assessment of sections was performed by a neuropathologist blinded to the protocol. Statistical analysis of the data was performed using analysis of variance and the chi-square test.Exposure to the gas mixture resulted in decreased maternal pO2 from 39.9 +/- 7.6 mm Hg in the control group to 28.8 +/- 2.0 mm Hg in the 2-hour hypoxia group (p0.05). No significant changes in maternal pH or pCO2 status have been noted. A total of 34 fetal rat brains served as controls and 26 brains as the hypoxia study group There was a significant increase in isolated neuronal damage, including necrosis and shrinkage of cells, with karyorrhexis (fragmentation and breakage of the nucleus) in the hippocampus, basal ganglia, thalamus, and hypothalamus in the hypoxemia rats as compared with controls.Transient maternal hypoxemia may cause neuronal necrosis in vulnerable regions of the fetal rat brain, including the hippocampus, basal ganglia, thalamus, and hypothalamus.

An association between intrauterine hypoxia and increased nucleated red blood cell (RBC) counts in the peripheral circulation has long been acknowledged. Higher counts reportedly are especially likely in neurologically impaired newborn infants. This study aimed at determining the effect of acute, severe hypoxia on peripheral nucleated RBC counts in the fetal rat. Maternal animals were randomized to either 2 hours of exposure in a hypoxia chamber or exposure to room air in a control chamber. The test chamber contained 9% oxygen, 3% carbon dioxide, and balanced nitrogen. Cesarean deliveries were carried out immediately after exposure and then at intervals up to 60 hours. There were 56 fetuses in each group. No differences in nucleated RBC counts were apparent immediately after hypoxic exposure, but counts were significantly higher in the hypoxia group 12 and 24 hours after exposure. Counts in the 2 groups did not differ significantly 36, 48, or 60 hours after exposure. Like in studies of the human fetus, nucleated RBC counts decreased with advancing fetal age. Near-term fetal rats in this study exhibited a delayed but transient increase in nucleated RBC counts in the peripheral circulation after an acute hypoxic episode. It may be that an increased nucleated RBC count will be a useful marker for fetal brain injury of hypoxic origin.

Fetal alcohol syndrome (FAS) is a leading cause of neurodevelopmental impairments (NDIs) in developed countries. Sensory deficits can play a major role in NDI, yet few studies have investigated the effects of prenatal alcohol exposure on sensory function. In addition, there is a paucity of information on the lifelong effects of prenatal alcohol exposure. Thus, we sought to investigate the effects of prenatal alcohol exposure on auditory function across the life span in an animal model. Based on prior findings with prenatal alcohol exposure and other forms of adverse prenatal environments, we hypothesized that animals prenatally exposed to alcohol would show an age-dependent pattern of (i) hearing and neurological abnormalities as postweanling pups, (ii) a substantial dissipation of such abnormalities in young adulthood, and (iii) a resurgence of such abnormalities in middle-aged adulthood.Pregnant rats were randomly assigned to an untreated control (CON), a pair-fed control (PFC), or an alcohol-treated (ALC) group. The ALC dams were gavaged with 6 mg/kg alcohol daily from gestation day (GD) 6 to 21. The PFC dams were gavaged daily from GD6 to GD21 with an isocaloric and isovolumetric water-based solution of maltose-dextrins and pair-fed to the ALC dams. The CON dams were the untreated group to which the ALC and CON groups were compared. Hearing and neurological functions in the offspring were assessed with the auditory brainstem response (ABR) at the postnatal ages of 22, 220, and 520 days.In accord with our hypothesis, ABR abnormalities were first observed in the postweanling pups, largely dissipated in young adulthood, and then resurged in middle-aged adulthood. This age-related pattern suggests that the ALC pups had a developmental delay that dissipated in young adulthood and an enhanced age-related deterioration that occurred in middle-aged adulthood. Such a pattern is consistent with the fetal programming hypothesis of adult-onset diseases (the Barker hypothesis).Our findings have important clinical implications for the assessment and management of (i) childhood hearing disorders and their comorbidities (i.e., speech-and-language, learning, and attention deficit disorders) and (ii) enhanced age-related hearing and neurological degeneration in middle-aged adulthood that can result from prenatal alcohol exposure. We recommend hearing evaluation be a part of any long-term follow-up for FAS patients and patients exposed to any adverse prenatal environment.

Objective This study was undertaken to identify the molecular basis of an arrest of descent. Study Design Human myometrium was obtained from women in term labor (TL; n=29) and arrest of descent (AODes; n=21). Gene expression was characterized using Illumina HumanHT-12 microarrays. A moderated Student t test and false discovery rate adjustment were applied for analysis. Confirmatory quantitative reverse transcription–polymerase chain reaction and immunoblot were performed in an independent sample set. Results Four hundred genes were differentially expressed between women with an AODes compared with those with TL. Gene Ontology analysis indicated enrichment of biological processes and molecular functions related to inflammation and muscle function. Impacted pathways included inflammation and the actin cytoskeleton. Overexpression of hypoxia inducible factor-1a, interleukin -6, and prostaglandin-endoperoxide synthase 2 in AODes was confirmed. Conclusion We have identified a stereotypic pattern of gene expression in the myometrium of women with an arrest of descent. This represents the first study examining the molecular basis of an arrest of descent using a genome-wide approach.

Consuming omega-3 fatty acids (omega-3 FA) during pregnancy and lactation benefits fetal and infant brain development and might reduce the severity of preterm births by prolonging pregnancy. However, diets that are relatively rich in omega-3 FA can adversely affect fetal and infant development and the auditory brainstem response (ABR), a measure of brain development and sensory function. We previously examined the offspring of female rats fed excessive, adequate or deficient amounts of omega-3 FA during pregnancy and lactation. The 24-day-old offspring in the Excess group, compared to the Control group, had postnatal growth retardation and poor hearing acuity and prolonged neural transmission times as evidenced by the ABR. The Deficient group was intermediate. The current study followed these offspring to see if these poor outcomes persisted into young adulthood. Based on prior findings, we hypothesized that the Excess and Deficient offspring would "catch-up" to the Control offspring by young adulthood. Female Wistar rats received one of the three diet conditions from day 1 of pregnancy through lactation. The three diets were the Control omega-3 FA condition (omega-3/omega-6 ratio approximately 0.14), the Excess omega-3 FA condition (omega-3/omega-6 ratio approximately 14.0) and Deficient omega-3 FA condition (omega-3/omega-6 ratio approximately 0% ratio). The Control diet contained 7% soybean oil; whereas the Deficient and Excess omega-3 FA diets contained 7% safflower oil and 7% fish oil, respectively. One male and female offspring per litter were ABR-tested as young adults using tone pip stimuli of 2, 4, 8 and 16 kHz. The postnatal growth retardation and prolonged neural transmission times in the Excess and Deficient pups had dissipated by young adulthood. In contrast, the Excess group had elevated ABR thresholds (hearing loss) at all tone pip frequencies in comparison to the Control and Deficient groups. The Deficient group had worse ABR thresholds than the Control group in response to the 8 kHz tone pips only. The Excess group also had ABR amplitude-intensity profiles suggestive of hyperacusis. These results are consistent with the Barker hypothesis concerning the fetal and neonatal origins of adult diseases. Thus, consuming diets that are excessively rich or deficient in omega-3 FA during pregnancy and lactation seems inadvisable because of risks for long-lasting adverse effects on brain development and sensory function.

Galectin-1 is a major anti-inflammatory protein expressed by the placenta and immune cells that can bias the character of inflammatory responses toward the Th2 type. Galectin-1 is expressed in immune privileged sites, it can facilitate immune tolerance and tumor immune escape, and it has been successfully used for the suppression of experimental autoimmune diseases as well as graft-versus-host disease in murine models. We propose that an abnormal immune response in some pregnancy complications may be associated with changes in placental expression of galectin-1. To test this hypothesis, we studied placental galectin-1 mRNA and protein expression and localization in women with preeclampsia (PE) and in those who delivered a small-for-gestational age (SGA) neonate.This cross-sectional study included pregnant women matched for gestational age at delivery in the following groups: (1) severe PE (n = 10), (2) severe PE complicated with SGA (n = 10), (3) SGA without PE (n = 10), and (4) controls (n = 10). Galectin-1 mRNA and protein were localized in placentas by in situ hybridization and immunofluorescence microscopy. Galectin-1 mRNA expression was determined by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR), and galectin-1 protein content by Western blot. Non-parametric statistics were used for analysis.(1) In normal term placentas, galectin-1 mRNA or immunofluorescence signals were detected in the trophoblasts, villous stromal cells, Hofbauer cells, endothelial cells of the villous blood vessels, and the villous stroma. (2) Placental galectin-1 mRNA expression was significantly higher in severe PE (with or without SGA) than in controls (1.47-fold, p = 0.004; 1.44-fold, p = 0.003, respectively) and in SGA (1.68-fold, p = 0.001; 1.64-fold, p = 0.001, respectively). (3) Trophoblasts in placentas of patients with severe PE had the most intense galectin-1 immunostaining.(1) We report for the first time the placental expression and localization of galectin-1 mRNA and demonstrate that the protein is abundantly present in third trimester human placentas. (2) Placental galectin-1 expression is higher in severe PE than in normal pregnancy regardless of the presence of SGA. (3) However, it is not altered in SGA without PE. We propose that the increased placental expression of galectin-1 in patients with severe PE may represent a fetal response to an exaggerated systemic maternal inflammation; thus, galectin-1 may be implicated in maternal-fetal immune tolerance in humans.

Laboratory rats prenatally exposed to alcohol, nicotine, amphetamine, undernutrition or hypoxia can exhibit shortened life span and other signs of enhanced age-related degeneration. We evaluated the possibility of similar effects following prenatal cocaine exposure. Pregnant rats received 20 or 40 mg/kg cocaine HCl subcutaneously (C20, C40), twice daily, from gestation days (GD) 7–20. Untreated control (UTC) and pair-fed control (PFC) groups were also used. The pregnant C40, C20, and PFC dams ate less food and gained less weight than the UTC dams did. The pregnant C40 and C20 dams drank more water than the UTC dams did, and the pregnant PFC dams drank less than the UTC dams did. The C40 and PFC offspring had delayed earflap openings. The C40 male and female offspring had lower birth weights than their cohorts in the other three groups. The C40 female and male offspring remained significantly underweight until postnatal day (PND) 28 and PND56, respectively. During young adulthood, the males and females in the C20, C40, and PFC groups had normal body weights. During old adulthood, however, the C20 and C40 males and the C20, C40, and PFC females developed reduced body weights as compared with their UTC cohorts. The C20 and C40 male offspring and the C20, C40, and PFC female offspring also had life spans that were 7–12% shorter than that of their UTC cohorts. Thus, groups that showed reduced body weights in old age also showed shorter life spans. These results provided converging evidence that prenatal cocaine exposure caused enhanced age-related degeneration. Observations on cardiac and other organ pathology were also made. Health implications for children born to cocaine-abusing women are discussed.

Objective: To develop an in vivo animal model for the study of the effects of intrauterine meconium exposure on the fetus. Methods: Timed pregnant Long-Evans rats were purchased on gestational day (GD) 12 and allowed to acclimate for at least 48 h prior to surgery. Laparotomy was performed and both uterine horns were exteriorized through the abdominal incision. A 26-gauge needle was used to inject either 0.1-cm3 sterile normal saline or a 20% meconium suspension into each individual gestational sac. The uterus was returned to the abdomen and the incision was closed. On GD 21 (term = 21 days) a cesarean section was completed and the number and viability of fetuses in each horn were recorded. Results: A total of 14 animals were involved in this pilot study. One rat underwent sham surgery with only intra-amniotic saline injection and 13/15 fetuses survived to term. Two animals that underwent surgery on day 18 expired Conclusion: We have established an in vivo animal model that allows for the examination of the effects of prolonged intrauterine meconium exposure on the fetus.

Objective: Our purpose was to evaluate the effect of seizures on kainate and α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor binding in maternal rat brain and whether maternal peripheral administration of magnesium sulfate can decrease this effect. Study Design: Rats were implanted with a bipolar electrode into the hippocampus. One week of recovery was allowed before breeding. Pregnant rats were randomly assigned to 1 of 4 groups, as follows: group 1, sodium chloride and no seizures (n = 5); group 2, magnesium sulfate and no seizures (n = 4); group 3, sodium chloride and seizures (n = 8); and group 4, magnesium sulfate and seizures (n = 9). Doses of sodium chloride or magnesium sulfate were administered every 20 minutes for 4 hours to all rats on gestational days 9, 11, 13, 15, 17, and 19, followed by seizure induction (groups 3 and 4). On gestational day 20, rats were perfused, brains were dissected, and cryostat sections were taken, labeled in vitro, and placed on Hyperfilm for 4 weeks. The ligands used included kainate receptor agonist and α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor agonist and antagonist. Optical density measurements of binding in 15 brain regions on each section were evaluated by 1- and 2-way analysis of variance. Results: Seizure activity was associated with decreased α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor binding of its agonist in pregnant rat brains (seizure effect, 25.9 ± 3.2 and 92.6 ± 3.4 fmol/mg tissue in hindbrain and forebrain, respectively; no seizure effect, 44.5 ± 4.7 and 110.7 ± 5.0 fmol/mg tissue in hindbrain and forebrain, respectively; P < .01). Magnesium administration was associated with increased binding of tritiated α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (magnesium effect, 44.9 ± 4.2 and 110.4 ± 4.5 fmol/mg tissue in hindbrain and forebrain, respectively; sodium chloride effect, 25.5 ± 3.7 and 92.9 ± 4.0 fmol/mg tissue in hindbrain and forebrain, respectively; P < .01). The same trend was seen with the kainate receptor in the hippocampus and hypothalamus, with a significant interaction effect between seizure and magnesium (P < .05). Conclusions: The mechanism for maternal rat brain injury resulting from seizure activity may be, at least in part, associated with alteration in the function of excitatory amino acid receptors. Administration of magnesium sulfate can counteract this effect and may reduce resultant maternal brain damage. (Am J Obstet Gynecol 2000;183:793-8.)

Objective: To determine whether severe maternal hypoxia affects fetal rat physical characteristics and causes neuronal damage, and whether magnesium sulfate can decrease these effects. Methods: At 17 days gestation, rats were randomly assigned to one of four groups that received saline injections and room air (n = 6), magnesium sulfate and room air (n = 5), saline and hypoxia (n = 5) or magnesium sulfate and hypoxia (n =5). Maternal magnesium sulfate or saline injections were given for 4 hours. In groups 3 and 4 this was followed by a hypoxia chamber protocol that included a gas mixture of 9% oxygen and 3% carbon dioxide for 2 hours. After 72 hours of recovery, fetuses were delivered abdominally, perfused transcardially, and brains removed intact. Fetal body and brain weight and size were measured. Brains were embedded in paraffin, sectioned, and stained. A neuropathologist masked to the protocol performed histologic grading of brain regions. Results: Exposure to the hypoxia chamber resulted in decreased maternal oxygen tension and pH (from 82.8 ± 20.0 to 49.2 ± 14.4 mmHg, and from 7.37 ± 0.05 to 7.20 ± 0.04, respectively; P < .005). Magnesium sulfate administration resulted in higher magnesium levels in blood (from 1.52 ± 0.2 to 3.77 ± 0.7 mg/dL; P < .001). The hypoxia protocol resulted in a significant decrease in fetal body and brain size, but not weight. Hypoxia also caused an increase in the proportion of fetal rats that had brain injury, including shrinkage of cells and karyorrhexis in the hippocampus and thalamus (from 0% to 38.1% and 38.9%, respectively; P < .05). Magnesium sulfate reduced these effects on fetal brain histopathology and size. Conclusion: Severe maternal rat hypoxia resulted in significant fetal neuronal damage and decreased fetal body and brain size. Maternal magnesium sulfate administration reduced the effect of hypoxia on fetal brain histopathology and size without affecting body size.

Objective The purpose of this study was to compare the transcriptome between the site of membrane rupture and the chorioamniotic membranes away from the site of rupture. Study Design The transcriptome of amnion and chorion (n = 20 each) from and distal to the site of rupture from women with spontaneous labor and vaginal delivery at term after spontaneous rupture of membranes was profiled with Illumina HumanHT-12 microarrays. Selected genes were validated with the use of quantitative reverse transcription–polymerase chain reaction. Results Six hundred seventy-seven genes were differentially expressed in the chorion between the rupture and nonrupture sites (false discovery rate 1.5). Quantitative reverse transcription–polymerase chain reaction confirmed the differential expression in 10 of 14 genes. Enriched biological processes included anatomic structure development, cell adhesion and signal transduction. Extracellular matrix–receptor interaction was the most impacted signaling pathway. Conclusion The transcriptome of fetal membranes after spontaneous rupture of membranes in term labor is characterized by region- and tissue-specific differential expression of genes that are involved in signature pathways, which include extracellular matrix–receptor interactions.

BRAIN DAMAGE IN PERI-ADOLESCENT RATS SEAN BLACKWELL, MORDECHAI HALLAK, JOHN HOTRA, WILLIAM KUPSKY, JERRIE REFUERZO, ROBERT SOKOL, YORAM SOROKIN, Wayne State University, Obstetrics/Gynecology, Detroit, MI Ben Gurion University Soroka Medical Center, Beer Sheva, Israel Wayne State University, Pathology, Detroit, MI Wayne State University, Obstetrics and Gynecology, Detroit, MI OBJECTIVE: To determine whether prolonged in utero meconium exposure is associated with histopathologic brain changes in the peri-adolescent rat. STUDY DESIGN: Timed pregnant Long-Evans rats underwent laparotomy on gestational day (GD) 20 (term = GD 21). Maternal animals received 0.1 cc of human clear amniotic fluid (CLAF) or ‘‘pea-soup’’ meconium-stained amniotic fluid (MSAF) injected into each gestational sac. The number of viable fetuses at the time of surgery and the number of liveborn pups were recorded. A neuropathologist masked to study group performed histopathologic grading of brain regions from animals who were euthanized following neurobehavioral testing at postnatal day 32-34. RESULTS: A total of 25 maternal animals underwent the surgical protocol (n = 12MSAF, n = 13CLAF). There was no difference in the rate of fetal survival betweenMSAF andCLAF animals (72.7% [91/129] vs 80% [121 /151]; P = 0.2). Brains from 42 offspring were studied following completion of neurobehavioral testing (MSAF = 21, CLAF = 21). No more than two offspring from each litter were included. MSAF-exposed fetuses were more likely to have evidence of neuronal damage in the hippocampus (CA 3 region) compared to CLAF (33.3 % vs 4.7%; P = 0.045) and had higher grades of damage in this region (0.38 ± 0.13 vs 0.09 ± 0.04; P = 0.027). There were no differences between groups in the other brain regions studied (cerebral cortex, basal ganglia, thalamus, hypothalamus, white matter of the forebrain, and cerebellum). CONCLUSION: In utero meconium exposure was associated with evidence of hippocampal injury in the peri-adolescent rat. Demonstration of histopathologic damage in this brain region is consistent with our previous work that showed impaired spatial learning in these offspring; lesions of the hippocampus have been correlated with deficits in this neurobehavioral function. Our finding supports the hypothesis that meconium itself may play a causative role in the development of fetal brain injury.