Different Days Of Pregnancy Research Articles

Effect of coumestrol on the biochemical constituents of ovary and uterus of pups of Female albino rats

In the current research, attempts were undertaken to evaluate the impact of coumestrol on some biochemical constituents of rats of F1 generation when these animals reached the ages of 2,4, and 6 months. The administration of coumestrol at different doses of 5,10 and 25 ug/kg during different days of pregnancy (Group-1 on the 10th and 13th day) and (Group-2 on the 15th and 18th day) caused a substantial rise in different parameters like the wet weight of uterus and ovary, protein contents, glycogen contents, the acid phosphatase, and alkaline phosphatase activity even at the age of 6 months.

ВВЕДЕНИЕ РЫБЬЕГО ЖИРА БЕРЕМЕННЫМ КРЫСАМ НА ФОНЕ СТРЕССА ПРЕДОТВРАЩАЕТ НАРУШЕНИЕ ОБРАЗОВАНИЯ И ДЕЙСТВИЯ ОКСИДА АЗОТА У ПОТОМСТВА

Objectives. To assess the possibility to prevent the disturbances of nitric oxide (NO) formation and action system in prenatally stressed rats with the help of fish oil administered to their mothers during pregnancy against the background of stress. Material and methods. Outbred pregnant rats weighing 180-220 g were divided into equal groups (n=10): «Pregnant control», «Pregnant stress», «Pregnant control + fish oil», «Pregnant stress+fish oil». Stress was reproduced by exposure to stressors on different days of pregnancy: food deprivation during one day, contact with cats’ feces during one day, and immobilization in water (20 minutes, t°=23±2). Rats of the groups «Pregnant control + fish oil» and «Pregnant stress + fish oil» received 0.1 ml of fish oil (Biosola, Lithuania) as a gavage at a daily dose of 60 mg/kg of eicosapentaenoic and docosahexaenoic acids; rats of groups «Pregnant control» and «Pregnant stress» received an equivalent volume of starch solution (0.1 ml). In 3-month-old offspring (n=181), systolic, diastolic, and mean arterial pressure (SBP, DBP, MAP, respectively) were measured noninvasively; the concentration of endothelial and inducible isoforms of NO-synthase (eNOS and iNOS, respectively), cyclic guanosine monophosphate (cGMP), asymmetric dimethylarginine (ADMA) was determined in blood serum by ELISA; the content of nitrates/nitrites (NO<sub>3</sub><sup>-</sup>/NO<sub>2</sub><sup>-</sup>), diene conjugates (DC), malondialdehyde (MDA), superoxide dismutase (SOD) and catalase was determined spectrophotometrically in blood serum. Results. Fish oil which was administered to pregnant rats under stress led to the increase of reduced compared with control males content of eNOS, cGMP, SOD, catalase, NO<sub>3</sub><sup>-</sup>/NO<sub>2</sub><sup>-</sup> (by 10.7%, 48.3%, 62.6%, 31.3%, 91.7%, respectively); the decrease of increased concentration of iNOS, ADMA, DC, MDA (by 21.8%, 37.4%, 61.2%, 75.9%, respectively) in the blood serum of male offspring. In female offspring of group «Pregnant stress + fish oil» the decrease of increased content of iNOS, DC, MDA (by 25.8%, 2.6 and 4.9 times, respectively) with the increase of reduced concentration of NO<sub>3</sub><sup>-</sup>/NO<sub>2</sub><sup>-</sup>, SOD (by 84.6%, 52%, respectively) were determined in the blood serum. The introduction of fish oil to pregnant rats against the background of stress prevented SBP, DBP, and MAP increasing in the offspring. Conclusions. The administration of fish oil to rats during pregnancy under chronic stress prevents the impairment of NO production and action in the offspring.

Effect of coumestrol on the histological feature of ovary of pups of F1 generation delivered from exposed mothers at different days of gestation

Phytoestrogens are the plant substances, which are structurally and functionally similar to steroids and produce estrogenic effects. It is well established that phytoestrogens when administered orally caused remarkable effects on the reproductive organs in females. It is also known that female rats, which consume more phytoestrogen for longer period, suffer from sterility. In the present study, efforts have been made to assess the effect of coumestrol on reproductive organs when exposed in uteroin mother and its effects on the development of postnatal pups.The administration of coumestrol during different days of pregnancy induced remarkable changes in the histological features of ovary of female rats of F1generation even at the age of 6 months.

Uterine Foxl2 regulates the adherence of the Trophectoderm cells to the endometrial epithelium

BackgroundForkhead Transcription Factor L2 (FOXL2) is a member of the forkhead family with important roles in reproduction. Recent studies showed that FOXL2 is expressed in human and bovine endometrium and that its levels fluctuate during pregnancy. In this study, we aimed at evaluating the expression and function of FOXL2 in embryo implantation.MethodsMouse uteri at different days of pregnancy were isolated and analyzed for the expression and localization of FOXL2. A lentiviral strategy was further employed to either knockdown or overexpress FOXL2 in non-receptive human endometrial AN3-CA cells and in receptive Ishikawa cells, respectively. These genetically modified cells were compared to cells infected with a control lentivirus to determine the function of FOXL2 in trophectoderm cells adherence to Endometrial Epithelium was associated with the expression of genes known to be involved in acquisition of uterine receptivity.ResultsWe report that FOXL2 is expressed in both, the luminal epithelium and the myometrium of the mouse uterus and that its expression declines prior to implantation. We found that endometrial cells expressing low FOXL2 levels, either endogenous or genetically manipulated, were associated with a higher attachment rate of mouse blastocysts or human Jeg3 spheroids and mouse blastocysts. In accordance, low-FOXL2 levels were associated with changes in the expression level of components of the Wnt/Fzd and apoptotic pathways, both of which are involved in uterine receptivity. Furthermore, FOXL2 expression was inversely correlated with G-protein signaling protein 2 (Rgs2) and cytokine expression.ConclusionsThese results suggest that FOXL2 interferes with embryo attachment. Better understanding of the function of FOXL2 in the uterus would possibly suggest novel strategies for treatment of infertility attributed to repeated implantation failure.

Long noncoding RNAs are dynamically regulated during β-cell mass expansion in mouse pregnancy and control β-cell proliferation in vitro.

Pregnancy is associated with increased β-cell proliferation driven by prolactin. Long noncoding RNAs (lncRNA) are the most abundant RNA species in the mammalian genome, yet, their functional importance is mainly elusive. Aims/hypothesis: This study tests the hypothesis that lncRNAs regulate β-cell proliferation in response to prolactin in the context of β-cell mass compensation in pregnancy. Methods: The expression profile of lncRNAs in mouse islets at day 14.5 of pregnancy was explored by a bioinformatics approach, further confirmed by quantitative PCR at different days of pregnancy, and islet specificity was evaluated by comparing expression in islets versus other tissues. In order to establish the role of the candidate lncRNAs we studied cell proliferation in mouse islets and the MIN6 β-cell line by EdU incorporation and cell count. Results: We found that a group of lncRNAs is differentially regulated in mouse islets at 14.5 days of pregnancy. At different stages of pregnancy, these lncRNAs are dynamically expressed, and expression is prolactin dependent in mouse islets and MIN6 cells. One of those lncRNAs, Gm16308 (Lnc03), is dynamically regulated during pregnancy, prolactin-dependent and islet-enriched. Silencing Lnc03 in primary β-cells and MIN6 cells inhibits, whereas over-expression stimulates, proliferation even in the absence of prolactin, demonstrating that Lnc03 regulates β-cell growth. Conclusions/interpretation: During pregnancy mouse islet proliferation is correlated with dynamic changes of lncRNA expression. In particular, Lnc03 regulates mouse β-cell proliferation and may be a crucial component of β-cell proliferation in β-cell mass adaptation in both health and disease.

Real-Time Monitoring of Placental Oxygenation during Maternal Hypoxia and Hyperoxygenation Using Photoacoustic Imaging.

PurposeThis preclinical study aimed to evaluate placental oxygenation in pregnant rats by real-time photoacoustic (PA) imaging on different days of gestation and to specify variations in placental oxygen saturation under conditions of maternal hypoxia and hyperoxygenation.Material and methodsPlacentas of fifteen Sprague-Dawley rats were examined on days 14, 17, and 20 of pregnancy with a PA imaging system coupled to high-resolution ultrasound imaging. Pregnant rats were successively exposed to hyperoxygenated and hypoxic conditions by changing the oxygen concentration in inhaled gas. Tissue oxygen saturation was quantitatively analyzed by real-time PA imaging in the skin and 3 regions of the placenta. All procedures were performed in accordance with applicable ethical guidelines and approved by the animal care committee.ResultsMaternal hypoxia was associated with significantly greater decrease in blood oxygen saturation (ΔO2 Saturation) in the skin (70.74% ±7.65) than in the mesometrial triangle (32.66% ±5.75) or other placental areas (labyrinth: 18.58% ± 6.61; basal zone: 13.13% ±5.72) on different days of pregnancy (P<0.001). ΔO2 Saturation did not differ significantly between the labyrinth, the basal zone, and the decidua. After the period of hypoxia, maternal hyperoxygenation led to a significant rise in oxygen saturation, which returned to its initial values in the different placental regions (P<0.001).ConclusionsPA imaging enables the variation of blood oxygen saturation to be monitored in the placenta during maternal hypoxia or hyperoxygenation. This first preclinical study suggests that the placenta plays an important role in protecting the fetus against maternal hypoxia.

Energy and protein requirements for maintenance of dairy goats during pregnancy and their efficiencies of use.

It has been suggested that maintenance requirements are similar among animals of different physiological stages; however, important physiological changes occur in the maternal body during pregnancy. Therefore, the aim of this study was to determine the energy and protein requirements for the maintenance of pregnant dairy goats and to estimate their efficiency of energy and protein utilization for maintenance and pregnancy. We used 66 multiparous pregnant goats having 49.0 ± 1.59 kg initial BW (around the third or fourth parturition) arranged in a randomized block design with a 3 × 3 factorial scheme including slaughter at different days of pregnancy (DOP; 80, 110, and 140 d) and feed restriction (0, 20, and 40% feed restriction). The comparative slaughter technique was used to estimate energy and protein maintenance requirements. Goats slaughtered at 140 DOP were subjected to digestibility trials at around 80, 110, and 140 DOP to estimate diet metabolizability and N balance (NBAL). Metabolizability decreased with feed restriction and was 63.3 ± 2.16, 55.7 ± 2.35, and 58.2 ± 2.30% at 0, 20, and 40% of feed restriction, respectively ( < 0.01). There was no effect of DOP on NE or the requirements of ME for maintenance (ME), which were 197 and 315 kJ/kg empty body weight (EBW), respectively, and the efficiency of ME utilization for maintenance (k) was 0.63. Similarly, DOP did not affect thedaily net protein requirements for maintenance (NP) estimated using the comparative slaughter technique (1.38 ± 0.512 g/kg EBW; = 0.003) or the NP estimated using NBAL (2.49 ± 0.594 g/kg EBW; < 0.01). The MP requirement for maintenance (MP) estimated using the comparative slaughter technique was not affected by DOP and was 3.22 g MP/kg EBW ( < 0.01). The efficiency of MP utilization for maintenance (k) was 0.43. The efficiency of ME utilization for pregnancy (k) increased with the progress of pregnancy and was 0.058, 0.10, and 0.19 at 80, 110, and 140 DOP, respectively. Similarly, the efficiency of MP utilization for pregnancy (k) increased with DOP and was 0.12, 0.21, and 0.43 at 80, 110, and 140 DOP, respectively. There was no evidence that pregnancy affected NE, ME, NP, and MP or k and k, which were also unaffected by DOP. However, k and k increased with pregnancy progress as a response to the physiological changes that pregnant females are subjected to.

Dynamic changes in sleep pattern during post-partum in normal pregnancy in rat model

To develop an animal model for studies on peri-partum sleep disorders, sleep patterns in female Wistar rats during pregnancy, post-partum and after weaning, were assessed and associated adaptive changes in their anxiety were examined. Adult nulliparous female rats, maintained in standard laboratory conditions with ad libitum food and water, were surgically implanted with electroencephalogram and electromyogram electrodes under anaesthesia for objective assessment of sleep-wakefulness (S-W). After post-surgical recovery, three control recordings of S-W were taken for 24h before the animals were kept for mating. After confirmation of pregnancy, S-W recordings were acquired during different days of pregnancy, post-partum lactation/nursing days, and also after weaning. Their anxiety levels were tested in the elevated plus maze. During pregnancy, sleep increased primarily due to increase in light non-REM sleep during dark period. There was an increase in non-REM sleep delta power after parturition, though the sleep was fragmented, especially during daytime. Simultaneous behavioural recording showed increased anxiety during third trimester of pregnancy and gradual reversal of it after parturition. This is the first report where diurnal and nocturnal variations in S-W and delta power, along with adaptive changes in anxiety, were studied before, during and after pregnancy. This study also provides an animal model for drug trials and studies on sleep disorders during peri-partum window.

Characterization of paneth cells in alpacas (Vicugna pacos, Mammalia, Camelidae).

Paneth cells are secretory epithelial cells of the innate immune system of the intestine of several mammals, including alpacas. Little is known about the latter; thus, in the present study we described the morphology and histochemical characteristics of Paneth cells in healthy fetuses, and young and adult alpacas. For this purpose, samples of duodenum, jejunum and ileum were taken from 6 fetuses at different days of pregnancy (between days 221-330), 66 offsprings (between 0 and 45-days-old) and 5 adult alpacas (>2-years-old). Samples were fixed in 10% buffered formalin and processed for histological and morphometrical analysis using HE and Masson Trichomićs technique. Immunohistochemistry was used to identify Paneth cells using anti-lysozyme antibody. In addition, the lectinhistochemichal binding-pattern of Paneth celĺs granules was evaluated. Lyzozyme was immunohistochemically detected in the granules of Paneth cells from day 283 of pregnancy in all the small intestinal sections of the studied fetuses. In newborn alpacas Paneth cells were initially found in the duodenum, but the following days (days 18-21 after birth) they were also found in the ileum. Their size gradually increased after birth, but then no significant differences were found. In adult alpacas the number was lower than offsprings. We suggest that Paneth cells early differentiate in the small intestine of alpacas, and the increase in their number during the first two weeks of life strongly support their possible involvement in the intestinal defensive functions against the enteric diseases that occur during the lactancy stage.

Sex distribution is a factor in teratogenically induced clefts and in the anti-teratogenic effect of thiamine in mice, but not in genetically determined cleft appearance.

Cleft lip and/or palate (CL/P) shows a gender-related distribution in human beings. The reason is unknown. This study analyzed the gender-related cleft appearance with respect to teratogenically and genetically determined cleft appearance and the response to thiamine (vitamin B1) supplementation. Cyclophosphamide (CPA; 0.6mg) and dexamethasone (0.25mg) were injected intraperitoneally to A/B-Jena mice on different days of pregnancy. The abortion and malformation rate in the A/B-Jena and A/WySn mice with genetically determined clefting was documented to be gender-specific. Vitamin B1 was given to A/B-Jena dams at different times during pregnancy before, simultaneously and after the teratogenic agent was given to the pregnant mothers. A/WySn mice received oral supplementation at different times during embryonic/fetal development. There were significantly more living female fetuses when mothers were treated with teratogens, and the embryo lethality and malformation affected more male individuals. However, the survival and malformation rate in A/WySn mice was not gender-specific. Especially in male fetuses, vitamin B1 decreased the teratogenic cleft rate (CPA: p<0.001, dexamethasone: p=0.6), whereas there was no effect in the A/WySn mice. There was a strong anti-teratogenic effect of vitamin B1, especially in the male fetuses. Genetically determined cleft appearance was not positively influenced. These findings confirm observations about cleft appearance in human beings.

Ovarian follicular development, estradiol and progesterone profile during different days of early pregnancy in buffaloes *

Improvement of reproductive performance of buffaloes requires a better understanding of the mechanisms controlling ovarian follicular growth and development. To study the follicular dynamics and ovarian steroid profile during early pregnancy, 6 buffaloes were selected on the basis of non return rate after insemination and subjected for ultrasonography to confirm the pregnancy as well as follicular development. The mean number of medium, large and total follicles was significantly lower on days 30, 40, 50 and 60 than day 20 of pregnancy indicating reduction in the follicular population with the advancement of pregnancy. There was no significant difference in the diameter of small and medium follicles on different days of pregnancy, however, large follicle significantly decreased with advancement of pregnancy. The progesterone levels fluctuated between 2.52±0.26 and 3.12±0.44 ng/ml until third month of pregnancy. The mean serum estradiol was significantly higher on day 0 and reduced into basal level on first and second month and remained low throughout the study period. In conclusion, on day 20 to 60 of pregnancy, the follicular development is continuous and the number and diameter of larger follicle is decreased as pregnancy advances in buffaloes.

Antiestrogenic and Anti-Inflammatory Potential of n-Hexane Fraction of Vitex negundo Linn Leaf Extract: A Probable Mechanism for Blastocyst Implantation Failure in Mus musculus.

The anti-implantation potential of different fractions of Vitex negundo Linn leaf extract was evaluated in female Swiss Albino mice. Animals from different groups were dosed orally either with 0.2% agar (vehicle) or with fractions of V. negundo leaf extract (n-hexane, chloroform, n-butanol, and remnant fractions) at 10:00 a.m., from day 1 to day 6 of pregnancy. The pregnant females from each group were sacrificed on different days of pregnancy (n = 6), and uterus was excised and used for estimation of lipid peroxidation and assay of superoxide dismutase activity as a marker for blastocyst implantation. Animals treated with n-hexane fraction showed altered level of superoxide anion radical and superoxide dismutase activity as compared to control animals. The probable mechanism by which this extract exhibits inhibition of blastocyst implantation is through the anti-inflammatory and antiestrogenic potential.

In vivo visualization of uterine mast cells by two-photon microscopy

Transgenic mice expressing fluorescent proteins in specific cell populations are widely used for the study of in vivo behavior of these cells. We have recently reported that uterine mast cells (uMCs) are important for implantation and placentation. However, their in vivo localization in uterus before and during pregnancy is unknown. Herein, we report the direct observation of uMCs in vivo using double-transgenic C57BL/6J Mcpt5-Cre ROSA26-EYFP mice with high expression of enhanced yellow fluorescent protein in MC protease 5 (Cma1 (Mcpt5))-expressing cells by intravital two-photon microscopy. We were able to monitor MCs live in utero during the murine estrous cycle and at different days of pregnancy. We demonstrated that uMCs accumulated during the receptive phase of the female (estrus) and persisted in large numbers at early pregnancy stages and around mid-gestation and declined in number in non-pregnant animals at diestrus. This intravital microscopy technique, including a custom-made microscope stage and the adaption of the surgical procedure, allowed the access of the uterus and implantations for imaging. The introduced application of intravital microscopy to C57BL/6J-Mcpt5-Cre ROSA26-EYFP mice offers a novel and powerful in vivo approach to further address the evident relevance of uMCs to reproductive processes with obvious clinical implications.

Regulation of the PI3-K/Akt Survival Pathway in the Rat Endometrium1

The occurrence of apoptosis and cell survival in the receptive uterus is intimately involved in the embryo implantation process in order to facilitate embryo attachment to the maternal endometrium. The initial stimulus leading to successful implantation might be triggered by the conceptus itself. By the end of rat embryo implantation, decidualization begins, followed by the regression of the decidua basalis on Day 14. The phosphatidylinositol 3-kinase (PI3-K) survival pathway and TGF-beta have been thought to play a role in this process. The objective of the present study was to investigate the regulation of the PI3-K/PTEN/Akt pathway in rat endometrium during pregnancy. Rats were killed on different days of pregnancy (Day 1-22 and postpartum) or pseudopregnancy (Day 1-9), and uteri were removed to collect endometrial tissues. The active form of Akt (pAkt) was increased at Day 5 of pregnancy and at Day 3 of pseudopregnancy as well as at Day 12 of pregnancy and at Day 1 postpartum. Of the three Akt isoforms (Akt1, Akt2, and Akt3), Akt3 was the only isoform phosphorylated at Day 5 during the implantation process and at postpartum as demonstrated by immunoprecipitation studies. PI3-K inhibition in vivo blocked Akt phosphorylation, reduced Smad2 phosphorylation, and reduced both TGF-beta2 and XIAP expression. PI3-K inhibition in cultured decidual cells led to inhibition of pAkt and decrease XIAP expression. These results suggest that Akt and XIAP may be important surviving signaling molecules by which apoptosis is regulated in the rat endometrium during pregnancy and that TGF-beta could be linked to this process.

Sex-dependent insulin like growth factor-1 expression in preattachment equine embryos

An adjustment of sex ratio of offspring to the conditions present at conception is seen in many mammals including horses. This depends on preferential survival of male embryos under conditions of high energy intake. In several species, growth factors including insulin like growth factor (IGF)-1 have been shown to promote embryonic development by decreasing apoptosis and increasing cell proliferation. We hypothesized that sex-related differences in IGF-1 expression in equine embryos during the phase of maternal recognition of pregnancy might exist and thus contribute to preferential survival of embryos from either of both sexes under specific environmental conditions. Insulin like growth factor-1 mRNA expression of in vivo-produced equine embryos on different days of pregnancy (Day 8, N = 6; Day 10, N = 8; Day 12, N = 14) was analyzed. Insulin like growth factor-1 mRNA expression was evaluated by reverse transcription quantitative polymerase chain reaction. The sex of the embryo was determined by detection of X-inactivation specific transcript (Xist) RNA and equine sex determining region of the Y chromosome DNA. Embryos positive for Xist expression were classified as female, and Xist negative and equine sex determining region of the Y chromosome positive embryos were classified as male. From 28 embryos tested, 15 (54%) showed positive Xist expression and were thus classified as female. Insulin like growth factor-1 mRNA expression was influenced by sex (P = 0.01) but not by day of pregnancy (relative expression of IGF-1 in relation to β-actin, Day 8: male 5.1 ± 2.1, female 11.4; Day 10: male 5.2 ± 1.6, female 17.4 ± 6.7; Day 12: male 2.6 ± 0.3, female 11.6 ± 2.4). Results demonstrate an increased expression of IGF-1 in female equine embryos. Sex-related influences on expression of the IGF system are probably related to a gradual X chromosome inactivation.

Lesões perinatais em cordeiros induzidas pela administração de Tetrapterys multiglandulosa (Malpighiaceae) a ovelhas em diferentes estágios de gestação

Foi realizada a intoxicação experimental em ovelhas em diferentes dias de gestação, 12 ovelhas foram dividas em quatro grupos. As ovelhas do Grupo 1 consumiram quatro doses de 5g/kg de folhas verdes durante quatro dias; ovinos do Grupo 2 consumiram duas doses de 10g/kg durante dois dias, o Grupo 3 consumiu uma dose de 20g/kg em um único dia e os ovinos do Grupo 4 não consumiram a planta (controle-negativo). Para testar a toxicidade da planta um ovino macho consumiu 5g/kg até manifestação dos sintomas. Não foram observados sinais clínicos da intoxicação nas ovelhas, mas três cordeiros tiveram morte perinatal, e um cordeiro morreu com três meses de idade; o ovino controle-positivo morreu após 38 dias de consumo diário da planta e os sinais clínicos foram taquipnéia, taquicardia, sonolência, incoordenação e fraqueza. Todos os quatro cordeiros e o ovino controle-positivo foram necropsiados e os achados de necropsia foram áreas esbranquiçadas no miocárdio, evidenciação do padrão lobular do fígado, pulmão vermelho enegrecido e rúmen acentuadamente distendido com presença de gases livres. Os achados histopatológicos foram fibrose cardíaca, necrose dos cardiomiócitos, congestão e edema pulmonar, congestão hepática centrolobular e degeneração esponjosa na região subcortical do encéfalo. Tetrapterys multiglandulosa demonstrou ser tóxica para os fetos ovinos em dosagens que não foram suficientes para induzir sinais clínicos nas ovelhas prenhes, e que a intoxicação pode ocorrer com morte de cordeiros logo após o parto, mesmo após meses de ter cessada a ingestão da planta.

Spatio-temporal expression patterns of anandamide-binding receptors in rat implantation sites: evidence for a role of the endocannabinoid system during the period of placental development

BackgroundAlthough there is growing evidence that endocannabinoids play a critical role in early pregnancy, there are no studies describing the possible targets for this system after implantation. The endometrial stroma, which undergoes extensive proliferation and differentiation giving rise to the decidua and the trophoblast cells that invade after the initial stages of implantation, are potential targets. Since high anandamide (AEA) levels, the main endocannabinoid, are detrimental to implantation and in order to gain insight into the role of the endocannabinoid system in the development of the fetoplacental unit, the spatio-temporal pattern of expression of the anandamide-binding receptors, CB1, CB2 and the vanilloid receptor (TRPV1), were investigated by quantitative RT-PCR, western blot and immunohistochemistry.MethodsRat uterine maternal tissues from different days of pregnancy were used to investigate the expression of CB1, CB2 and vanilloid receptors by quantitative RT-PCR, western blot and immunohistochemistry.ResultsThe data indicate that all the three receptors were expressed in decidualized cells and placenta. Interestingly, CB1 and CB2 were also expressed in smooth muscle cells of maternal blood vessels and in endovascular trophoblast cells, whereas TRPV1 was mainly expressed in uterine natural killer (uNK) cells and in the longitudinal muscle layer throughout pregnancy. In all tissues, CB2 protein was present at a lower level than CB1.ConclusionThese observations support a role for the endocannabinoid system during the period of decidualization and placental development.

Modification of the effect of nifedipine in the pregnant rat myometrium: The influence of progesterone and terbutaline

Aims The aims of the study were to investigate the effects of nifedipine on potassium chloride (KCl)-evoked rat uterine contractions on different days of pregnancy in vitro, and the alterations in the effects of nifedipine on combination with terbutaline or progesterone. Main methods In rat myometrial rings taken on different days of pregnancy, rhythmic contractions were evoked with KCl in an isolated organ bath. Key findings The relaxing effect of nifedipine was most expressed in the 25 mM KCl-induced uterine contractions, reaching the maximum on the last day of pregnancy (day 22). This effect was decreased by progesterone pretreatment in vivo. Synergism was observed in the uterus-relaxing effect of nifedipine +terbutaline, though the extent of potentiation depended on the sequence of administration of the two compounds. When terbutaline was added first in a single dose, the maximal inhibitory effect of nifedipine was lower. This decrease in the inhibition was suspended by a Ca 2+-poor buffer, indicating the role of Ca 2+ channel activating effect of terbutaline. Significance It is concluded that the uterus-relaxing effect of nifedipine is weakened by progesterone and may be enhanced by low concentrations of β-mimetics. However, the administration of terbutaline cannot precede the administration of nifedipine.

Teratogenic effect of retinoic acid in swiss mice

To identify the types of malformations resulting from the administration of retinoic acid (RA) to Swiss mice on different days of pregnancy. Twenty-four pregnant Swiss mice were divided into 4 groups of 6 animals each. The experimental groups received a single intraperitoneal injection of RA (70 mg/kg) on gestational days 7, 8 and 9 (D7, D8 and D9), while control animals (C) received only saline solution. Were obtained: exencephaly (C:0; D7:16.1%; D8:25.4%; D9:0), myelomeningocele (C:0; D7:25.8%, D8:30.9%, D9:0), spina bifida occulta (C:0, D7:29%, D8:41.8%, D90), gastroschisis (C:0, D7:6.4% D8:5.4%, D9:0), omphalocele (C:0, D7:6.4%, D8:14.5%, D9:0), lower limb alterations (C:0, D7:74.1%, D8:80%, D9:0), imperforated anus (C:0, D7:100%, D8:100%, D9:100%), and tail agenesis/alteration (C: D7:100%, D8:100%, D9:100%). The experimental model using Swiss mice proved to be efficient in the induction of the different types of defects, with the eighth gestational day being the one that most favored the induction of neural tube defect, omphalocele, gastroschisis, lower limb defects, imperforated anus and tail agenesis/alteration. On this basis, this is a useful model for future investigation of neural development and of the formation of the appendicular skeleton.

TGF-beta expression during rat pregnancy and activity on decidual cell survival

BackgroundDuring early rat pregnancy, trophoblast of the tiny embryo joins with the endometrium and epithelial cells undergo apoptosis. Near the end of pregnancy, regression of the decidua basalis (DB) is also observed (from day 14 to 20). However, little is known about the intra-cellular and molecular mechanisms involved in apoptosis regulation in the uterus during pregnancy. The objective of the present study was to investigate the presence and the developmental expression of transforming growth factor-beta isoforms (TGF-beta well known differentiation factor) in the rat endometrium throughout pregnancy and its action in vitro using cultured endometrial stromal cells.MethodsIn vivo: Rats were killed at different days of pregnancy (days 2–20) and uteri removed to collect endometrial protein extracts or the uteri were fixed, embedded and sectioned for immunohistochemistry (IHC) and in situ cell death analyses using TdT-mediated dUTP nick end labeling (TUNEL). In vitro: Rats were ovariectomized and decidualization was induced using sex steroids. Endometrial stromal decidual cells were then collected and cultured.ResultsAn increase of apoptosis in the DB on days 14, 16 and 18 was observed. Cleaved caspase-3 was clearly detected during regression of the DB by Western analysis and immunofluorescence. Western analyses using endometrial protein extracts demonstrated that TGF-beta1, TGF-beta2 and TGF-beta3 were highly expressed at the time of DB regression (day 14). During early pregnancy, TGF-beta1 and -beta2 expressions raised at days 5.5 to 6.5. TGF-beta3 protein was not detected during early pregnancy. IHC analyses revealed that TGF-beta1 and -2 were found surrounding both epithelium (luminal and glandular) in the stroma compartment at the implantation site, and TGF-beta3 was mainly located surrounding endometrial epithelium in the stroma compartment. Smad2 phosphorylation was increased at the time of DB regression. In vitro studies using decidual endometrial stromal cells revealed that TGF-beta1 induced apoptosis and Smad2 phosphorylation. Moreover, TGF-beta1 reduced both Akt (a well known survival factor) phosphorylation and XIAP (X-linked inhibitor of apoptosis protein) expression in decidual endometrial stromal cells in vitro.ConclusionTaken together, these results suggest that TGF-beta isoforms are regulated differently during pregnancy and may have an important role in the control of apoptosis and cell survival at specific stages during pregnancy.