Diabetes in pregnancy: influence of genetic background and maternal diabetic state on the incidence of skeletal malformations in the fetal rat

1986 ◽  
Vol 113 (3_Suppl) ◽  
pp. S66-S73 ◽  
Author(s):  
Ulf J. Eriksson ◽  
V. Elisabeth Dahlström ◽  
Hans O. Lithell

Abstract. Female Sprague-Dawley rats from two different substrains (denoted U and H rats) were made manifest diabetic (MD) with a single iv injection of streptozotocin 2–4 weeks before mating. In some MD animals insulin treatment was started 1–3 weeks before mating (denoted MDI rats) and in a majority of these animals the treatment was interrupted during two days of pregnancy, i.e. gestational days 2 + 3, 4 + 5, 6 + 7, 8 + 9 or 10 + 11. The pregnant rats were killed on gestational day 20. The offspring of MD and MDI rats of the U substrain showed skeletal malformations (micrognathia and sacral dysgenesis) at a rate up to 19%, whereas the MD and MDI fetuses of the H strain did not display any skeletal malformations. Offspring of the U strain with sacral dysgenesis exhibited lack of a tail and no staining of osseous and cartilagenous tissue in the sacral-caudal region, suggesting total absence of vertebrae. The offspring of the dibetic U rats tended to be more readily resorbed, were smaller and tended to have slightly larger placentae than those of the diabetic H rats. The severity of the diabetic state in pregnant and nonpregnant female rats – as reflected by body and kidney weights, blood levels of HbA1c, carbohydrate and lipid metabolites – did not differ significantly between the U and H rats. These results are in concert with the notion that congenital malformations result from a teratogenic insult in a genetically predisposed organism. The described malformation-prone rat strain (U) may be a suitable model for the future elucidation of teratological mechanisms in diabetic pregnancy.

2019 ◽  
Vol 38 (6) ◽  
pp. 476-486
Author(s):  
France-Helene Paradis ◽  
Anne Marie Downey ◽  
Francine Beaudry ◽  
Clémentine Pinêtre ◽  
Sisse Ellemann-Laursen ◽  
...  

Species-dependent differences in relative incidence of spontaneous variations and malformations should be considered in the assessment of the translational value of reproductive and developmental safety assessments. The objective of this evaluation was to compare litter parameters and the frequency of external, visceral, and skeletal malformations and variations across species in the Sprague-Dawley rat, New Zealand White rabbit, and Göttingen minipig and to determine whether notable differences exist. Pregnant female rats (n = 824), rabbits (n = 540), and minipigs (n = 70) from vehicle control groups were included in the analysis, equating to 10,749 rat, 5,073 rabbit, and 378 pig fetuses collected at term by cesarean delivery. Preimplantation loss was more frequent than postimplantation loss in the rat and rabbit, whereas the opposite was observed in the minipig. Several external and visceral malformations and variations such as domed head, bent tail, abdominal edema, and anal atresia were observed in all 3 species. Visceral malformations of the heart and major blood vessels were remarkably more frequent in the minipig and rabbit, respectively; ventricular and atrium septum defects were observed in 1.9% and 2.1%, respectively, for the minipig fetuses, whereas they were observed in equal or less than 0.02% among the rat and rabbit fetuses evaluated in this study. Understanding species-dependent differences in spontaneous variations and malformations can be useful for the interpretation of embryo–fetal development study results. The current analysis identified relevant differences between commonly used species in reproductive toxicology with potential implications for data assessment.


1985 ◽  
Vol 5 (6) ◽  
pp. 1035-1043 ◽  
Author(s):  
Behzad S. Samimi ◽  
Stephen B. Harris ◽  
Ann De Peyster

Cyclohexanone (CH), a solvent and thinner that has extensive use in industry, was investigated for developmental effects using pregnant Sprague-Dawley rats exposed to 100, 250 or 500 ppm concentrations in an inhalation chamber for seven hours per day from days 5 through 20 of pregnancy. Controls were exposed to room air. Maternal weight gain at 250 and 500 ppm CH was only slightly lower than in the control dams, and a grey mottling of the lungs was seen in a few of the CH-exposed dams. There were no significant differences between the CH and control groups in fetal weight, resorption sites, fetal death or sex ratio. External and soft tissue examinations revealed no significant incidence of malformations or variations in CH-exposed animals. A slight increase in the mean percent of rudimentary ribs per litter was observed in the 250 and 500 ppm CH-exposed groups. However, no significant numbers of skeletal malformations were noticed in either the CH or room air control groups. It was concluded that respiratory exposure of rats to as much as 500 ppm CH during organogenesis was unlikely to be developmentally toxic.


Development ◽  
1977 ◽  
Vol 41 (1) ◽  
pp. 289-294
Author(s):  
R. R. Schmidt ◽  
K. P. Chepenik ◽  
B. V. Paynton

Pregnant rats were subjected to either a folic-acid-deficient regimen that produces multiple congenital skeletal malformations, or a control folic-acid-supplemented regimen. Fetal limbs were extirpated on days 16 and 18 of gestation, pooled from each litter, homogenized, and aliquots set aside for hydroxyproline, protein and DNA determinations. We found that (1) the amount of protein recovered per treated limb was approximately half that of controls on both days, (2) the amount of protein recovered per treated or controlday-18 limb was twice that of a day-16 limb, (3) treated limbs constituted the same percentage of total body weight as in controls on day 16, but a smaller percentage than in controls on day 18, and (4) the concentration of hydroxyproline (μg/mg protein) was significantly less for treated limbs than for controls on day 18 of gestation. We noted also that: (1) lowest hydroxyproline concentrations were found in limbs from treated fetuses with gross limb malformations, (2) intermediate concentrations were found in limbs of treated fetuses not exhibiting gross limb malformations, and (3) highest concentrations were found in control limbs. We suggest that the treatment resulted in (1) a decreased rate of accumulation of protein in limbs prior to day 16, but not from day 16 to day 18, (2) a decreased rate of accumulation of some non-protein component(s) in treated limbs from day 16 to day 18, and (3) an altered collagen metabolism.


2001 ◽  
Vol 91 (4) ◽  
pp. 1828-1835 ◽  
Author(s):  
Nicole Stupka ◽  
Peter M. Tiidus

The effects of estrogen and ovariectomy on indexes of muscle damage after 2 h of complete hindlimb ischemia and 2 h of reperfusion were investigated in female Sprague-Dawley rats. The rats were assigned to one of three experimental groups: ovariectomized with a 17β-estradiol pellet implant (OE), ovariectomized with a placebo pellet implant (OP), or control with intact ovaries (R). It was hypothesized that following ischemia-reperfusion (I/R), muscle damage indexes [serum creatine kinase (CK) activity, calpain-like activity, inflammatory cell infiltration, and markers of lipid peroxidation (thiobarbituric-reactive substances)] would be lower in the OE and R rats compared with the OP rats due to the protective effects of estrogen. Serum CK activity following I/R was greater ( P < 0.01) in the R rats vs. OP rats and similar in the OP and OE rats. Calpain-like activity was greatest in the R rats ( P < 0.01) and similar in the OP and OE rats. Neutrophil infiltration was assessed using the myeloperoxidase (MPO) assay and immunohistochemical staining for CD43-positive (CD43+) cells. MPO activity was lower ( P < 0.05) in the OE rats compared with any other group and similar in the OP and R rats. The number of CD43+ cells was greater ( P < 0.01) in the OP rats compared with the OE and R rats and similar in the OE and R rats. The OE rats had lower ( P < 0.05) thiobarbituric-reactive substance content following I/R compared with the R and OP rats. Indexes of muscle damage were consistently attenuated in the OE rats but not in the R rats. A 10-fold difference in serum estrogen content may mediate this. Surprisingly, serum CK activity and muscle calpain-like activity were lower ( P< 0.05) in the OP rats compared with the R rats. Increases in serum insulin-like growth factor-1 content ( P < 0.05) due to ovariectomy were hypothesized to account for this finding. Thus both ovariectomy and estrogen supplementation have differential effects on indexes of I/R muscle damage.


2009 ◽  
Vol 87 (6) ◽  
pp. 460-470 ◽  
Author(s):  
Claude Lajoie ◽  
Viviane El-Helou ◽  
Cindy Proulx ◽  
Robert Clément ◽  
Hugues Gosselin ◽  
...  

Rapamycin represents a recognized drug-based therapeutic approach to treat cardiovascular disease. However, at least in the female heart, rapamycin may suppress the recruitment of putative signalling events conferring cardioprotection. The present study tested the hypothesis that rapamycin-sensitive signalling events contributed to the cardioprotective phenotype of the female rat heart after an ischemic insult. Rapamycin (1.5 mg/kg) was administered to adult female Sprague–Dawley rats 24 h after complete coronary artery ligation and continued for 6 days. Rapamycin abrogated p70S6K phosphorylation in the left ventricle of sham rats and the noninfarcted left ventricle (NILV) of 1-week postmyocardial-infarcted (MI) rats. Scar weight (MI 0.028 ± 0.006, MI+rapamycin 0.064 ± 0.004 g) and surface area (MI 0.37 ± 0.08, MI+rapamycin 0.74 ± 0.03 cm2) were significantly larger in rapamycin-treated post-MI rats. In the NILV of post-MI female rats, rapamycin inhibited the upregulation of eNOS. Furthermore, the increased expression of collagen and TGF-β3 mRNAs in the NILV were attenuated in rapamycin-treated post-MI rats, whereas scar healing was unaffected. The present study has demonstrated that rapamycin-sensitive signalling events were implicated in scar formation and reactive fibrosis. Rapamycin-mediated suppression of eNOS and TGF-β3 mRNA in post-MI female rats may have directly contributed to the larger infarct and attenuation of the reactive fibrotic response, respectively.


2020 ◽  
Vol 319 (2) ◽  
pp. F192-F201
Author(s):  
Lindsey A. Ramirez ◽  
Ellen E. Gillis ◽  
Jacqueline B. Musall ◽  
Riyaz Mohamed ◽  
Elizabeth Snyder ◽  
...  

We have previously shown that hypertensive female rats have more regulatory T cells (Tregs), which contribute more to blood pressure (BP) control in female versus male rats. Based on known protective properties of Tregs, the goal of the present study was to investigate the mechanisms by which female rats maintain Tregs. The present study was designed to 1) compare the impact of three hypertension models on the percentage of renal Tregs and 2) test the hypothesis that nitric oxide synthase (NOS) inhibition prevents increases in renal Tregs and exacerbates renal damage in female Sprague-Dawley rats. Rats (11–14 wk old) were randomized to one of the following four groups: control, norepinephrine (NE) infusion, angiotensin II infusion, or the NOS inhibitor Nω-nitro-l-arginine methyl ester (l-NAME) in drinking water. BP was measured via tail cuff. After 2 wk of treatment, kidneys were isolated and processed to measure Tregs via flow cytometric analysis and renal injury via urinary albumin excretion, plasma creatinine, and histological analyses. Hypertensive treatments increased BP in all experimental animals. Increases in BP in norepinephrine-and angiotensin II-treated rats were associated with increases in renal Tregs versus control. In contrast, l-NAME treatment decreased Tregs compared with all groups. l-NAME treatment modestly increased albumin excretion. However, plasma creatinine was comparable among the groups, and there was no histological evidence of glomerular or tubular injury. This study provides insights into the mechanisms regulating renal Tregs and supports that an intact NOS system is crucial for female rats to have BP-related increases in renal Tregs.


2020 ◽  
Vol 36 (2) ◽  
pp. 63-75
Author(s):  
Saman Saedi ◽  
Mohammad Reza Jafarzadeh Shirazi ◽  
Mohammad Javad Zamiri ◽  
Mehdi Totonchi ◽  
Mohammad Dadpasand ◽  
...  

Cadmium (Cd) has been associated with several physiological problems including reproductive and endocrine system dysfunction resulting in temporary infertility. The principal objective of this project was to investigate the effects of prepubertal exposure to toxic doses of Cd on puberty onset, the endocrine system, and follicular development. For this purpose, 16 female Sprague-Dawley rats weaned on postnatal day (PND) 21 were randomly divided into 4 groups ( n = 4 per group). The treatments were as follows: 0, 25, 50, and 75 mg/kg/day of cadmium chloride (CdCl2) by oral gavage from PND 21 to observation of first vaginal opening (VO). The results demonstrated that prepubertal exposure to different doses of CdCl2 delays the age of VO, first diestrus, and first proestrus via altering the concentrations of estradiol and progesterone. The low level of these steroid hormones contributed to lower differentiation and maturation of follicles and it finally led to reduced ovarian reservoir of follicles and impaired follicular development. The number of atretic follicles and secondary follicles with premature cavity increased in rats that received a high dose of CdCl2, whereas the number of secondary follicles and corpora luteum decreased in the same circumstances. Taken together, these data suggest that prepubertal exposure to toxic doses of Cd delays the onset of puberty via disorderliness in the concentration of steroid hormones and reduces the ovarian reservoir of follicles, as well as folliculogenesis.


2020 ◽  
Vol 151 ◽  
pp. 01058
Author(s):  
Siti Aisyah ◽  
Ekowati Handharyani ◽  
Nurliani Bermawie ◽  
Agus Setiyono

The purpose of the research was to study the potency of Murraya koenigii leaves extract to overcome the mammary tumor in Sprague Dawley rat. Thirty-five female rats were divided into seven groups: control (P1), tumor without therapy (P2), methotrexate group (P3), curative groups (P4 and P5) were given extract after the tumor was formed, and preventive groups (P6 and P7) were given extract before the tumor was formed with dose of 300 and 400 mg/kg, respectively. The induction of mammary tumor in rats were carried out using 7,12 dimethylbenz(α) anthracene (DMBA) subcutaneously. Bodyweight and tumor size were measured every week for 4 weeks. At the end of treatment, rats were euthanized and mammary glands were collected for histopathological examination. The result showed tumor size in P2 was significantly higher (p<0.05) than in other groups. On the other hand, tumor size in P4 and P6 were significantly smaller (p<0.05) compared to P5 and P7. Histopathological changes showed PMN cells, 1-3 layers of cuboid epithelial and solid collagen fibers proliferation in P2, while in P3 to P7 showed moderate collagen fibers proliferation. In conclusion, the administration of the extract at a dose of 300 mg/kg can decelerate tumor development in Sprague Dawley rat mammary gland.


2000 ◽  
Vol 347 (3) ◽  
pp. 787-795
Author(s):  
Damian BRAUZE ◽  
Danuta MALEJKA-GIGANTI

β-Naphthoflavone (β-NF) is a widely used inducer of phase-I and phase-II enzymes controlled by aryl hydrocarbon receptor (AhR). Studies of competitive binding with 3H-labelled 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3-methylcholanthrene (3-MC) and benzo[a]pyrene (B[a]P) have shown that β-NF is a high-affinity ligand for AhR and also for polycyclic aromatic hydrocarbon (PAH)-binding protein, both soluble proteins of rat liver in 8 S and 4 S fractions, respectively, of sucrose gradients. This study examined binding of [3H]β-NF to liver cytosolic proteins of female Sprague-Dawley rats. Treatment of rats with β-NF, 3-MC, TCDD or α-naphthoflavone (α-NF) increased the specific [3H]β-NF binding to liver cytosol up to 125-fold that of vehicle (corn oil)-treated rats (< 100 fmol/mg of protein). Sucrose gradients revealed a large 4 S and a small 8 S peak of radioactivity from [3H]β-NF binding to cytosols of β-NF-, 3-MC-, TCDD- or α-NF-treated rats. Whereas co-incubation with the unlabelled β-NF eliminated both peaks, co-incubation with 2,3,7,8-tetrachlorodibenzofuran (TCDF) eliminated only the 8 S peak. The sucrose density gradient from [3H]TCDD binding to cytosol of β-NF- or TCDD-treated rats yielded a small 4 S and a larger 8 S peak; only the latter was abolished by co-incubation with TCDF. Thus, the patterns of sedimentation, distribution and elimination of radioactivity from the 8 S fraction of the liver cytosols from β-NF-, 3-MC-, TCDD- or α-NF-treated rats were characteristic for the AhR, whereas those from the 4 S fraction appeared specific for [3H]β-NF binding. The data indicate that potent AhR agonists, TCDD, 3-MC and β-NF, and to a lesser extent α-NF, a weak AhR agonist, induce a 4 S [3H]β-NF-binding protein in liver cytosol of female rats. α-NF, β-NF and 3-MC were effective competitors (80-85% inhibition) of the [3H]β-NF-specific binding to the β-NF-, 3 MC- or TCDD-induced 4 S protein, whereas several PAHs including B[a]P and benzo[e]pyrene were only weak competitors. The increased [3H]β-NF binding was not associated with glycine N-methyltransferase activity. Hence, the 4 S [3H]β-NF-binding protein described herein differs from the constitutive 4 S PAH-binding protein of rat liver cytosols in the inducibility by β-NF and 3-MC, ligand-binding characteristics, and lack of glycine N-methyltransferase activity. Gel filtration on Sephacryl of liver cytosols from β-NF-treated rats indicated a molecular mass of ≈ 42 kDa for [3H]β-NF-bound protein and suggested that it was derived from a large mass component that before the radioligand binding was eluted with the void volume of the gel and sedimented in a 7 S fraction of the sucrose gradient. The [3H]β-NF binding activity was not eluted with glutathione S-transferase Ya, aldehyde-3-dehydrogenase or DT-diaphorase [NAD(P)H: quinone oxidoreductase] activities, which are AhR-controlled and β-NF-inducible. Further studies are needed to determine the identity and function of this novel protein which may be involved either directly or indirectly (as a carrier protein) in xenobiotic metabolism in vivo.


2000 ◽  
Vol 279 (2) ◽  
pp. F353-F357 ◽  
Author(s):  
Ali A. Khraibi

The objective of this study was to test the hypothesis that a decrease in renal interstitial hydrostatic pressure (RIHP) accounts for the blunted pressure natriuresis during pregnancy. RIHP was measured in nonpregnant (NP; n = 9), midterm pregnant (MP; 12–14 days after conception; n = 10), and late-term pregnant (LP; 18–21 days after conception; n = 12) female Sprague-Dawley rats at two renal perfusion pressure (RPP) levels (99 and 120 mmHg). At the lower RPP level, RIHP was 5.9 ± 0.3 mmHg for NP, 3.4 ± 0.4 mmHg for MP ( P < 0.05 vs. NP), and 2.9 ± 0.1 mmHg for LP ( P < 0.05 vs. NP) rats. The increase in RPP from 99 to 120 mmHg resulted in pressure natriuretic and diuretic responses in all groups; however, the increases in fractional excretion of sodium (ΔFENa), urine flow rate (ΔV), and ΔRIHP were significantly greater ( P < 0.05) in NP compared with both MP and LP rats. ΔFENa, ΔV, and ΔRIHP were 2.06 ± 0.28%, 81.44 ± 14.10 μl/min, and 3.0 ± 0.5 mmHg for NP; 0.67 ± 0.13%, 28.03 ± 5.28 μl/min, and 0.5 ± 0.2 mmHg for MP; and 0.48 ± 0.12%, 18.14 ± 4.70 μl/min, and 0.4 ± 0.1 mmHg for LP rats. In conclusion, RIHP is significantly lower in pregnant compared with nonpregnant rats at similar RPP levels. Also, the ability of pregnant rats to increase RIHP in response to an increase in RPP is blunted. These changes in RIHP may play an important role in the blunted pressure natriuresis and contribute to the conservation of sodium and water that is critical for fetal growth and development during normal pregnancy.


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