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1.
In humans, low birth weight and increased placental weight can be associated with cardiovascular disease in adulthood. Low birth weight and increased placental size are known to occur after fetal alcohol exposure or prenatal glucocorticoid administration. Thus the effects of removing the alcohol-induced increase in maternal corticosterone by maternal adrenalectomy on predictors of cardiovascular disease in adulthood were examined in rats. Alcohol exposure of dams during the last 2 wk of gestation resulted in significantly decreased fetal weight and increased placental weight on gestational day 21. Adult female, but not male, offspring of alcohol-consuming mothers exhibited left ventricular hypertrophy. Placental 11beta-hydroxysteroid dehydrogenase-2 (11beta-HSD-2) mRNA levels, measured by Northern blot, were decreased in females but not males. Adrenalectomy of alcohol-consuming dams reversed the increase in placental weight and the decrease in female placental 11beta-HSD-2 expression and eliminated the left ventricular hypertrophy of adult female offspring. These data suggest that alcohol-induced changes in placental 11beta-HSD-2 mRNA levels and left ventricular weight are coupled in female offspring only and depend on maternal adrenal status.  相似文献   

2.
Exposure of pregnant rats to morphine, from day 11 to day 18 of gestation, was previously reported to induce both an adrenal atrophy and hypoactivity of the glucocorticoid function in newborns at term, but did not affect, in vitro, the responsiveness of those glands to adrenocorticotrophin hormone (ACTH) concerning corticosterone release. Moreover, these effects were mediated by maternal hormones from the adrenal glands. In the present work, we investigated the effects of a prenatal morphine exposure on the mineralocorticoid activity of the adrenals in neonates. The first aim of the present study was to determine in these newborns 1) the adrenal and plasma aldosterone concentrations at birth time and during the early postnatal period 2) the plasma levels of Na+ and K+ at birth time, 3) the in vitro responsiveness of the newborn adrenals to angiotensin II (A(II)) and ACTH. The second aim of our study was to investigate the mineralocorticoid activity of the adrenals in newborns from adrenalectomized mothers treated with morphine during gestation. According to present data morphine given to intact mothers induced in newborns a severe adrenal atrophy but increased adrenal aldosterone content and plasma aldosterone level. However, prenatal morphine was unable to affect significantly Na+/K+ ratio in both mothers and newborns. In vitro, the adrenals of neonates from morphine-treated mothers were unresponsive to An and ACTH for promoting aldosterone release; in contrast, aldosterone secretion was significantly stimulated by high potassium levels (55 mEq). Maternal adrenalectomy performed one day before the beginning of morphine treatment prevented morphine-induced adrenal atrophy but was unable to affect significantly the adrenal mineralocorticoid function of the offspring. Such data suggest that a prenatal morphine exposure stimulated both aldosterone synthesis and release in neonates. However, this basal hyperfunction did not appear to be coupled with an enhanced adrenal responsivity to AII or ACTH. Prenatal morphine-induced hyperactivity of the mineralocorticoid function of the newborn adrenals, which drastically contrast with hypoactivity of the glucocorticoid one, was independent of adrenal factors from maternal origin.  相似文献   

3.
边疆晖  吴雁  刘季科 《兽类学报》2004,24(2):139-144
本研究了根田鼠母体捕食应激对其子代出生、断乳和成体体重、窝性比及死亡率的作用,检验Trivers—Willard模型的2个前提条件、母体应激激素在母体投资中的作用,以及母体捕食应激效应与该模型的关系。将妊娠根田鼠母体暴露于其捕食艾鼬,母体应激子代的出生和断乳体重均显降低;到成体,雄性体重有此效应,而雌性体重则接近对照。出生窝性比无变化,但成体窝性比向雌性偏斜。不同年龄阶段的死亡率无显变化,但累计死亡率明显增大。处理雄性子代在断乳和成体时的皮质酮含量显增高,而雌性子代则无显变化,从而验证了Trivers-Willard模型的2个前提条件,提出应激母体激素参与母体对子代的投资观点,并认为,母体捕食应激使根田鼠子代成体窝性比向雌性偏斜的生理投资符合进化稳定对策。  相似文献   

4.
To investigate the early renal alterations due to severe maternal protein restriction (MPR) Wistar dams received 23% (normal protein, NP) or 5% (low protein, LP) chow during gestation and lactation periods. In NP offspring at birth, the cortex-to-medulla (C/M) ratio was 35% greater in female than in male offspring and the mature/immature glomeruli ratio was lower in both sexes of LP offspring than in the matched NP ones (by 20%). At birth and at weaning the kidney of the LP offspring showed fewer glomeruli (40% less) than the age-matched NP offspring. The NP female offspring had almost 20% fewer glomeruli than the matched male offspring. At weaning, the number of glomeruli was positively correlated with BM at birth (R=0.86; P<0.001). The effects of gender and maternal protein restriction, both individually and overall, based on biometrical and stereological parameters were: day 1, MPR largely responsible for the majority of alterations observed in LP groups, however gender influenced C/M ratio; day 21, MPR and gender interacted and modified the number of glomeruli per kidney. The early adverse of MPR effect on renal development is disproportionate between mature and immature glomeruli at birth leading to fewer glomeruli at weaning. This supports epidemiological data in humans underlying why fetuses with low birth weight carry an increased risk of mortality from chronic diseases in adulthood, including hypertension.  相似文献   

5.
We studied the effect of maternal stress evoked by a severe stressor from the cues of predation risk during gestation on the growth of offspring in root volesMicrotus oeconomus Pallas, 1776. Body mass of both male and female offspring was significantly reduced in the period from birth to weaning. Females showed compensatory growth after weaning, whereas males maintained low body mass at weaning into adulthood. Maternal stress led to an elevated plasma corticosterone level in male offspring, but did not affect that of female offspring. Corticosterone levels remained elevated in males from stressed dams into adulthood. Increased levels of plasma corticosterone may have led to the inhibition of pituitary growth hormone and a chronically abnormal energy mobilization, considering the greater energy and metabolic requirements of male offspring, this may account for the sex-specific differences in compensatory growth. We suggest that in the high stress situation, endocrine-based sex-biased effects of maternal stress as a primary factor can lead to long-term physical and ecological consequences for male offspring.  相似文献   

6.
-Di(2-ethylhexyl) phthalate (DEHP), a typical endocrine-disrupting chemical (EDC), is widely used as plasticizer. DEHP exposure in humans is virtually ubiquitous, and those undergoing certain medical procedures can be especially high. In this study, we investigated whether developmental DEHP exposure disrupted glucose homeostasis in the rat and whether this was associated with the early impairment in endocrine pancreas. Pregnant Wistar rats were administered DEHP (1.25 and 6.25 mg·kg(-1)·day(-1)) or corn oil throughout gestation and lactation by oral gavage. Body weight, glucose and insulin tolerance, and β-cell morphometry and function were examined in offspring during the growth. In this study, developmental DEHP exposure led to abnormal β-cell ultrastructure, reduced β-cell mass, and pancreatic insulin content as well as alterations in the expression of genes involved in pancreas development and β-cell function in offspring at weaning. At adulthood, female DEHP-exposed offspring exhibited elevated blood glucose, reduced serum insulin, impaired glucose tolerance, and insulin secretion. Male DEHP-exposed offspring had increased serum insulin, although there were no significant differences in blood glucose at fasting and during glucose tolerance test. In addition, both male and female DEHP-exposed offspring had significantly lower birth weight and maintained relatively lower body weight up to 27 wk of age. These results suggest that developmental exposure to DEHP gives rise to β-cell dysfunction and the whole body glucometabolic abnormalities in the rat. DEHP exposure in critical periods of development can be a potential risk factor, at least in part, for developing diabetes.  相似文献   

7.
Epidemiological and animal studies suggest that the alteration of hormonal and metabolic environment during fetal and neonatal development can contribute to development of metabolic syndrome in adulthood. In this paper, we investigated the impact of maternal high-fat (HF) diet on hypothalamic leptin sensitivity and body weight gain of offspring. Adult Wistar female rats received a HF or a control normal-fat (C) diet for 6 wk before gestation until the end of the suckling period. After weaning, pups received either C or HF diet during 6 wk. Body weight gain and metabolic and endocrine parameters were measured in the eight groups of rats formed according to a postweaning diet, maternal diet, and gender. To evaluate hypothalamic leptin sensitivity in each group, STAT-3 phosphorylation was measured in response to leptin or saline intraperitoneal bolus. Pups exhibited similar body weights at birth, but at weaning, those born to HF dams weighed significantly less (-12%) than those born to C dams. When given the HF diet, males and females born to HF dams exhibited smaller body weight and feed efficiency than those born to C dams, suggesting increased energy expenditure programmed by the maternal HF diet. Thus, maternal HF feeding could be protective against adverse effects of the HF diet as observed in male offspring of control dams: overweight (+17%) with hyperleptinemia and hyperinsulinemia. Furthermore, offspring of HF dams fed either C or HF diet exhibited an alteration in hypothalamic leptin-dependent STAT-3 phosphorylation. We conclude that maternal high-fat diet programs a hypothalamic leptin resistance in offspring, which, however, fails to increase the body weight gain until adulthood.  相似文献   

8.
Naltrexone modulates growth in infant rats   总被引:2,自引:0,他引:2  
I S Zagon  P J McLaughlin 《Life sciences》1983,33(24):2449-2454
Naltrexone, a potent opiate antagonist, had both stimulatory and inhibitory effects on somatic growth in preweaning rats depending on dose. Daily injections of 50 mg/kg naltrexone, which blocked morphine-induced analgesia for 24 hr/day, resulted in increased body and organ weights, and acceleration in the appearance of physical characteristics and maturation of spontaneous motor activity. Naltrexone in a dosage of 1 mg/kg, which blocked morphine-induced analgesia for 4 hr/day, had the opposite effects. These results show that naltrexone can modulate growth, and suggest a role for the endorphins and opiate receptors in developmental events.  相似文献   

9.
The effects of cadmium (Cd) were evaluated in offspring exposed from birth until weaning (neonatal day 0–21) and 4 weeks after exposure cessation focusing on iron (Fe) and zinc (Zn) levels in organs and hematological parameters. Wistar female rats were administered 50 mg Cd/L in drinking water (Cd-exposed) for 4 weeks before mating and during 3 weeks of gestation plus 3 weeks of lactation. Controls were supplied drinking water. At birth, part of Cd-exposed dams’ litters was cross-fostered to control dams (CCd group) and their control litters were cross-fostered to Cd-exposed dams (CdC group). This procedure enabled to discern the effects of gestational, lactational and gestational plus lactational Cd exposure until weaning in F1 offspring. Elements were analyzed by atomic absorption spectrometry; hematological parameters manually; and histopathological changes by light microscopy. Gestational plus lactational exposure in Cd-exposed dams and their offspring increased Cd and decreased Fe levels, increased Zn in dams and decreased Zn and body weights in 11- and 21-day pups. In 21-day weanling pups, decreased red blood cell (RBC) count, hemoglobin and hematocrit values and increased reticulocytes in peripheral blood were also found with concomitant histopathological finding of extramedullary hematopoiesis in the liver. In cross-fostered pups with gestational exposure (CCd pups), Fe in the liver decreased on day 11 and Zn increased in the kidney on day 21 whereas in pups with lactational exposure (CdC pups) Zn in the brain decreased on day 11 and Fe decreased in the liver and brain on day 21. Regardless of exposure cessation at weaning, in offspring with gestational plus lactational exposure (Cd-exposed) body weights, kidney and brain Fe levels and RBC and hemoglobin remained decreased in blood until puberty. Furthermore Zn levels increased in the liver, kidney and brain. It was concluded that gestational plus lactational Cd exposure caused decreases in Fe and Zn levels and hematotoxic effects in F1 offspring more pronouncedly than exposure during either gestational or lactational period alone and the adverse effects of maternally mediated Cd exposure continued after exposure cessation into adulthood.  相似文献   

10.
In this study, we investigated the effect of morphine on the mucosal immune system using fragment cultures of ileal segments, Peyer's patches (PPs), and mesenteric lymph nodes. Mice were implanted s.c. with a morphine slow release pellet. Control groups received a naltrexone slow release pellet, a placebo pellet, or both a morphine and a naltrexone pellet. After 48 h, mice were orally immunized with cholera toxin (CT) and were boosted orally 1 wk later. Animals were sacrificed 1 wk after the booster immunization, and PPs, mesenteric lymph nodes, and ileal segments were cultured in 24-well plates for 12 days. Morphine resulted in a highly significant inhibition of CT-specific IgA and IgG production in fragment culture supernatants of all three tissues compared with placebo. Naltrexone blocked the reduction in Ab levels induced by morphine, indicating that the effect is opioid receptor mediated. Morphine did not significantly alter total IgA levels in any of the tissue culture supernatants. Morphine also inhibited CT-specific IgA and IgG levels in serum. By flow cytometry, morphine did not alter the lymphoid cell composition in PPs compared with placebo. The effect of morphine on TGF-beta, IL-5, and IL-6 mRNA expression in PPs and ileal segments was determined following oral immunization with CT. Morphine significantly decreased TGF-beta mRNA compared with that in the placebo group, and naltrexone blocked this effect. These results indicate that morphine inhibits Ag-specific IgA responses in gut-associated lymphoid tissue at least partially through the inhibition of TGF-beta, a putative IgA switch factor, in the gastrointestinal tract.  相似文献   

11.
Pregnant Rockland-Swiss (R-S) mice were injected with sesame oil or 250 or 500 micrograms of progesterone (P) on Days 12 through 16 of gestation and the postpartum aggressive behavior of their female offspring was examined in adulthood. Both doses of P significantly increased the intensity of aggression (number of attacks) exhibited by the female offspring toward an adult male intruder. The low dose of P also produced significant increases in relative anogenital distance. These effects were seen in the absence of any effects on body weight at birth or in adulthood, or on reproductive performance. The findings support previous research, in both animals and humans, showing that prenatal brain differentiation and subsequent behavior are masculinized by prenatal exposure to progesterone.  相似文献   

12.
Shift work during pregnancy is associated with an increased risk for preterm birth and low birth weight. However, the impact upon the long term health of the children is currently unknown. In this study, we used an animal model to determine the consequences of maternal shift work exposure on the health of the adult offspring. Pregnant rats were exposed to chronic phase shifts (CPS) in their photoperiod every 3-4 days throughout gestation and the first week after birth. Adult offspring were assessed for a range of metabolic, endocrine, circadian and neurobehavioural parameters. At 3 months of age, male pups exposed to the CPS schedule in utero had increased adiposity (+29%) and hyperleptinaemia (+99% at 0700h). By 12 months of age, both male and female rats displayed hyperleptinaemia (+26% and +41% respectively) and hyperinsulinaemia (+110% and +83% respectively). 12 month old female CPS rats displayed poor glucose tolerance (+18%) and increased insulin secretion (+29%) in response to an intraperitoneal glucose tolerance test. In CPS males the glucose response was unaltered, but the insulin response was reduced by 35%. The glucose response to an insulin tolerance test was decreased by 21% in CPS females but unaltered in males. Disruption of circadian rhythmicity during gestation resulted in gender dependent metabolic consequences for the adult offspring. These results highlight the need for a thorough analysis of shift work exposure in utero on the health of the adult offspring in humans.  相似文献   

13.
The mu opioid receptor, MOR, displays spontaneous agonist-independent (basal) G protein coupling in vitro. To determine whether basal MOR signaling contributes to narcotic dependence, antagonists were tested for intrinsic effects on basal MOR signaling in vitro and in vivo, before and after morphine pretreatment. Intrinsic effects of MOR ligands were tested by measuring GTPgammaS binding to cell membranes and cAMP levels in intact cells. beta-CNA, C-CAM, BNTX, and nalmefene were identified as inverse agonists (suppressing basal MOR signaling). Naloxone and naltrexone were neutral antagonists (not affecting basal signaling) in untreated cells, whereas inverse agonistic effects became apparent only after morphine pretreatment. In contrast, 6alpha- and 6beta-naltrexol and -naloxol, and 6beta-naltrexamine were neutral antagonists regardless of morphine pretreatment. In an acute and chronic mouse model of morphine-induced dependence, 6beta-naltrexol caused significantly reduced withdrawal jumping compared to naloxone and naltrexone, at doses effective in blocking morphine antinociception. This supports the hypothesis that naloxone-induced withdrawal symptoms result at least in part from suppression of basal signaling activity of MOR in morphine-dependent animals. Neutral antagonists have promise in treatment of narcotic addiction.  相似文献   

14.
Endocrine disruptors, chemicals that disturb the actions of endogenous hormones, have been implicated in birth defects associated with hormone-dependent development. Phytoestrogens are a class of endocrine disruptors found in plants. In the current study we examined the effects of exposure at various perinatal time periods to genistein, a soy phytoestrogen, on reproductive development and learning in male rats. Dams were fed genistein-containing (5 mg/kg feed) food during both gestation and lactation, during gestation only, during lactation only, or during neither period. Measures of reproductive development and body mass were taken in the male offspring during postnatal development, and learning and memory performance was assessed in adulthood. Genistein exposure via the maternal diet decreased body mass in the male offspring of dams fed genistein during both gestation and lactation, during lactation only, but not during gestation only. Genistein decreased anogenital distance when exposure was during both gestation and lactation, but there was no effect when exposure was limited to one of these time periods. Similarly, spatial learning in the Morris water maze was impaired in male rats exposed to genistein during both gestation and lactation, but not in rats exposed during only one of these time periods. There was no effect of genistein on cued or contextual fear conditioning. In summary, the data indicate that exposure to genistein through the maternal diet significantly impacts growth in male offspring if exposure is during lactation. The effects of genistein on reproductive development and spatial learning required exposure throughout the pre- and postnatal periods.  相似文献   

15.
16.
Co-administration of dextromethorphan (DM) with morphine during pregnancy and throughout lactation has been found to reduce morphine physical dependence and tolerance in rat offspring. No evidence was presented, however, for the effect of DM co-administered with morphine during pregnancy on morphine-induced reward and behavioral sensitization (possibly related to the potential to induce morphine addiction) in morphine-exposed offspring. Conditioned place preference and locomotor activity tests revealed that the p60 male offspring of chronic morphine-treated female rats were more vulnerable to morphine-induced reward and behavioral sensitization. The administration of a low dose of morphine (1 mg/kg, i.p.) in these male offspring also increased the dopamine and serotonin turnover rates in the nucleus accumbens, which implied that they were more sensitive to morphine. Co-administration of DM with morphine in the dams prevented this adverse effect of morphine in the offspring rats. Thus, DM may possibly have a great potential in the prevention of higher vulnerability to psychological dependence of morphine in the offspring of morphine-addicted mothers.  相似文献   

17.
In this study, we evaluated the molecular mechanisms involved in morphine-induced macrophage apoptosis. Both morphine and TGF-beta promoted P38 mitogen-activated protein kinase (MAPK) phosphorylation, and this phosphorylation was inhibited by SB 202190 as well as by SB 203580. Anti-TGF-beta Ab as well as naltrexone (an opiate receptor antagonist) inhibited morphine-induced macrophage P38 MAPK phosphorylation. Anti-TGF-beta Ab also attenuated morphine-induced p53 as well as inducible NO synthase expression; in contrast, N(G)-nitro-L-arginine methyl ester, an inhibitor of NO synthase, inhibited morphine-induced P38 MAPK phosphorylation and Bax expression. Morphine also enhanced the expression of both Fas and Fas ligand (FasL), whereas anti-FasL Ab prevented morphine-induced macrophage apoptosis. Moreover, naltrexone inhibited morphine-induced FasL expression. In addition, macrophages either deficient in FasL or lacking p53 showed resistance to the effect of morphine. Inhibitors of both caspase-8 and caspase-9 partially prevented the apoptotic effect of morphine on macrophages. In addition, caspase-3 inhibitor prevented morphine-induced macrophage apoptosis. These findings suggest that morphine-induced macrophage apoptosis proceeds through opiate receptors via P38 MAPK phosphorylation. Both TGF-beta and inducible NO synthase play an important role in morphine-induced downstream signaling, which seems to activate proteins involved in both extrinsic (Fas and FasL) and intrinsic (p53 and Bax) cell death pathways.  相似文献   

18.
Hematological and serum biochemical values of dams and offspring of Sprague-Dawley rats were measured during late gestation, lactation and postweaning. In dams, slightly low erythrocytic parameters, high platelets and high frequency of neutrophils were seen after parturition although WBC showed no marked changes. On Day 20 of gestation, glucose and triglycerides were extremely high and TP and albumin were low. These changes may be attributed to pregnancy or parturition. In fetuses on Day 20 of gestation and offspring immediately after birth, erythrocytes showed anisocytosis, polychromasia, basophilic stipplings and Howell-Jolly bodies and erythroblasts were found. RBC was low. MCV and MCH were extremely high, compared to adult erythrocyte levels. Hemoglobin and hematocrit slightly decreased before weaning. RBC, hemoglobin and hematocrit increased with age and reached adult levels by Day 56. MCV and MCH values decreased, towards adult levels, until weaning. Platelets rapidly increased and reached adult levels before weaning. WBC increased after birth having higher counts in males than in females on Day 35 and thereafter. Glucose, TP and albumin increased with age and reached adult levels by Day 28. ALP was high in fetuses and changed with age having two peaks similar to those reported in man. Cholesterols gradually increased after birth and had a peak on Day 14. Urea nitrogen, inorganic phosphorus and calcium were slightly high in fetuses and preweaned offspring. Potassium was high in fetuses but no age-related trends were seen in offspring.  相似文献   

19.
Perinatal loss of Ts65Dn Down syndrome mice   总被引:2,自引:0,他引:2  
Roper RJ  St John HK  Philip J  Lawler A  Reeves RH 《Genetics》2006,172(1):437-443
Ts65Dn mice inherit a marker chromosome, T(17(16))65Dn, producing segmental trisomy for orthologs of about half of the genes on human chromosome 21. These mice display a number of phenotypes that are directly comparable to those in humans with trisomy 21 and are the most widely used animal model of Down syndrome (DS). However, the husbandry of Ts65Dn mice is complicated. Males are sterile, and only 20-40% of the offspring of Ts65Dn mothers are trisomic at weaning. The lower-than-expected frequency of trisomic offspring has been attributed to losses at meiosis, during gestation and at postnatal stages, but no systematic studies support any of these suppositions. We show that the T(17(16))65Dn marker chromosome is inherited at expected frequency and is fully compatible with development to midgestation. Disproportional loss of trisomic offspring occurs in late gestation and continues through birth to weaning. Different maternal H2 haplotypes are significantly associated with the frequency of trisomy at weaning in patterns different from those reported previously. The proportion of trisomic mice per litter decreases with age of the Ts65Dn mother. These results provide the first statistical and numerical evidence supporting the prenatal and perinatal pattern of loss in the Ts65Dn mouse model of DS.  相似文献   

20.
We have previously described a theoretical model in humans, called “Similarities in the Inequalities”, in which extremely unequal social backgrounds coexist in a complex scenario promoting similar health outcomes in adulthood. Based on the potential applicability of and to further explore the “similarities in the inequalities” phenomenon, this study used a rat model to investigate the effect of different nutritional backgrounds during gestation on the willingness of offspring to engage in physical activity in adulthood. Sprague-Dawley rats were time mated and randomly allocated to one of three dietary groups: Control (Adlib), receiving standard laboratory chow ad libitum; 50% food restricted (FR), receiving 50% of the ad libitum-fed dam’s habitual intake; or high-fat diet (HF), receiving a diet containing 23% fat. The diets were provided from day 10 of pregnancy until weaning. Within 24 hours of birth, pups were cross-fostered to other dams, forming the following groups: Adlib_Adlib, FR_Adlib, and HF_Adlib. Maternal chow consumption and weight gain, and offspring birth weight, growth, physical activity (one week of free exercise in running wheels), abdominal adiposity and biochemical data were evaluated. Western blot was performed to assess D2 receptors in the dorsal striatum. The “similarities in the inequalities” effect was observed on birth weight (both FR and HF groups were smaller than the Adlib group at birth) and physical activity (both FR_Adlib and HF_Adlib groups were different from the Adlib_Adlib group, with less active males and more active females). Our findings contribute to the view that health inequalities in fetal life may program the health outcomes manifested in offspring adult life (such as altered physical activity and metabolic parameters), probably through different biological mechanisms.  相似文献   

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