From pregnancy to parturition, Sprague-Dawley rats were daily administered a low protein diet to establish a model of intrauterine growth restriction. From the 12th day of pregnancy, 300 mg/kg taurine was daily added ...From pregnancy to parturition, Sprague-Dawley rats were daily administered a low protein diet to establish a model of intrauterine growth restriction. From the 12th day of pregnancy, 300 mg/kg taurine was daily added to food until spontaneous delivery occurred. Brain tissues from normal neonatal rats at 6 hours after delivery, neonatal rats with intrauterine growth restriction, and neo- natal rats with intrauterine growth restriction undergoing taurine supplement were obtained for fur- ther experiments. The terminal deoxyribonucleotidyl transferase (TdT)-mediated biotin-16-dUTP nick-end labeling assay revealed that the number of apoptotic cells in the brain tissue of neonatal rats with intrauterine growth restriction significantly increased. Taurine supplement in pregnant rats reduced cell apoptosis in brain tissue from neonatal rats with intrauterine growth restriction. Immu- nohistochemical staining revealed that taurine supplement increased glial cell line-derived neuro- trophic factor expression and decreased caspase-3 expression in the cerebral cortex of intrauterine growth-restricted fetal rats. These results indicate that taurine supplement reduces cell apoptosis through the glial cell line-derived neurotrophic factor-caspase-3 signaling pathway, resulting in a protective effect on the intrauterine growth-restricted fetal rat brain.展开更多
Dexmedetomidine has significant neuroprotective effects. However, whether its protective effects can reduce neurotoxicity caused by isoflurane in fetal brain during the second trimester of pregnancy remains unclear. I...Dexmedetomidine has significant neuroprotective effects. However, whether its protective effects can reduce neurotoxicity caused by isoflurane in fetal brain during the second trimester of pregnancy remains unclear. In this study, timed-pregnancy rats at gestational day 14 spontaneously inhaled 1.5% isoflurane for 4 hours, and were intraperitoneally injected with dexmedetomidine at dosages of 5, 10, 20, and 20 μg/kg 15 minutes before inhalation and after inhalation for 2 hours. Our results demonstrate that 4 hours after inhaling isoflurane, 20 μg/kg dexmedetomidine visibly mitigated isoflurane-induced neuronal apoptosis, reversed downregulation of brain-derived neurotrophic factor expression, and lessened decreased spatial learning and memory ability in adulthood in the fetal rats. Altogether, these findings indicate that dexmedetomidine can reduce neurodegeneration induced by isoflurane in fetal rats during the second trimester of pregnancy. Further, brain-derived neurotrophic factor participates in this process.展开更多
BACKGROUND: Both c-Fos protein and nitricoxide synthase (NOS) have been used as general indexes in relative research about neurons, but it is lack of reports that c-Fos protein and NOS are applied synchronously to ...BACKGROUND: Both c-Fos protein and nitricoxide synthase (NOS) have been used as general indexes in relative research about neurons, but it is lack of reports that c-Fos protein and NOS are applied synchronously to study the neurons of hypoxic fetal rats in uterus. OBJECTIVE: To study the effect of hypoxia in uterus on the expression of c-Fos protein and NOS in neurons of cerebral cortex from fetal rats and whether Angelica sinensis has the protective effect on these neurons in hypoxia. DESIGN: Randomized control experiment.SETTING : Department of Histology and Embryology, Luzhou Medical College.MATERIALS : Twelve adult female Wistar rats in oestrum and 1 male Wistar rat with bodymass from 220 to 250 g were chosen. Parenteral solution of Angelica sinensis mainly contained angelica sinensis, 10 mL/ampoule, was provided by Department of Agent of the Second Hospital Affiliated to Hubei Medical University (batch number: 01062310). METHODS : This experiment was completed in the Department of Histology and Embryology of Luzhou Medical College from September 2003 to June 2004. ①Twelve adult female Wistar rats in oestrum and 1 male Wistar rat were housed in one rearing cage. Vaginal embolus was performed on conceive female rat at 8: 00 am next day. On the 15^th conceiving day, all conceiving rats were divided randomly into three groups: control group, hypoxia group and Angelica group with 4 in each group. Rats in hypoxia group and Angelica group were modeled with hypotonic hypoxia in uterus. Angelica group: Rats were injected with 8 mL/kg Angelica sinensis injection through caudal veins before hypoxia. Hypoxia group: Rats were injected with the same volume of saline. Control group: Rats were not modeled and fed with normal way. ② Twenty embryos of rats were chosen randomly from each group and then routinely embedded in paraffin. Paraffin sections were cut from the brain of embryos to anterior fontanelle. Double-label staining was used to detect the expression of nNOS and c-Fos in neurons of cerebral cortex from embryos of rats. OLYMPUS Bx-50 microscope was used to observe sections and DP12 digit camera was also used under 400 times to detect types of cells. Under microscope, the number of c-Fos, NOS, c-Fos/NOS positive neurons in cerebral cortex from embryos of rats were counted in 2 fields with magnification of 400 in one section per animal. ③ The data in experiments were analyzed by one-way analysis of variance (ANOVA) followed by q test. MAIN OUTCOME MEASURES: ① Results of immunohistochemical double-label staining of c-Fos/NOS from cerebral cortex; ② Comparison of amount immunohistochemical double-label staining of c-Fos/NOS positive cells from cerebral cortex. RESULTS:① The positive NOS cells and c-Fos/NOS cells in the three groups were mainly distributed in cerebral cortex, but positive c-Fos neurons were not observed. ② Positive NOS cells and c-Fos/NOS cells in hypoxia group were more than those in control group (76.55±12.02, 50.45±10.39; 33.35±7.42, 26.35±6.67, P 〈 0.05), but those in Angelica group were less than those in hypoxia group (51.70±9.82, 35.65±8.37, P 〈 0.05). CONCLUSION: Hypoxia can stimulate the increase of expression of c-Fos protein and NOS in neurons of cerebral cortex. However, Angelica sinensis can decrease this expression so as to play a protective role in cerebral neurons of hypoxic fetal rats.展开更多
Objective: To establish a simple, effective and high-purity primary culture method for fetal rat hippocampalneurons. Methods: Wistar rats of gestational age 18 days were taken and the brain tissue was separated unde...Objective: To establish a simple, effective and high-purity primary culture method for fetal rat hippocampalneurons. Methods: Wistar rats of gestational age 18 days were taken and the brain tissue was separated under themicroscope. Single neuronal cells were obtained by digestion with Brain Dissociation Kit, and then were seeded incell plates to observe the basic morphologic structure after 24h, 3d, and 5d. Immunofluorescence of microtubuleassociated protein 2 was applied to assess cell purity of the culture. Results: The hippocampal neurons obtained inthis culture method are in good condition and grow vigorously. On the 7th day after culture, the purity of neuronswas up to 99.62%. Conclusion: The method is simple and effective for obtaining the high-purity and stableneurons.展开更多
Objective To observe the spatial and temporal distribution of collagen in fetal and adult rats wounds. Methods The organization of collagen deposition in fetal and adult rats skin wounds were observed by using van Gie...Objective To observe the spatial and temporal distribution of collagen in fetal and adult rats wounds. Methods The organization of collagen deposition in fetal and adult rats skin wounds were observed by using van Gieson stain. The methods of immunohistochemistry and in situ hybridization were applied to examine collagen type Ⅰ and Ⅲ peptide and mRNA localization at serial time point during wound healing. Results Collagen type Ⅰ and Ⅲ were present in wounds of both fetal and adult rats, but the timing and pattern of collagen deposition varied. In the fetus, collagen wes detected by 48h postwounding (PW), but uns not present in the adult wounds until 5d PW. N in situ hybridization, signals in the area of the fetal wound were clearly greater and with increased number of cells as compered to that in the adjacent unwounded tissue. Adult rat wounds had evidence in increased signals of procollagen type Ⅰ and Ⅲ production by wound fibroblasts on day 5. Collagen deposited and wes arranged in reticular pattern as that of the nounal in fetal wounds. While in the adult wound, collagen deposited in the fashion of course bundles. bundles Conclusion Fetal rat wounds appeared to produce collagen mainly by an increased number offibroblasts in the area of the wound. In contrast, adult rat wounds underwent fibroblast migration and induction of procollagen mRNA synthesis. Our results Suggest that the deposition of collagen type Ⅰ and Ⅲ is regulated by their gene expression. Chllagen type Ⅲ plays an important role in the arrangement of collagen depoition.展开更多
Smoking during pregnancy is a major source of fetal exposure to numerous harmful agents present in tobacco smoke. Lung development involves complex biochemical processes resulting in dramatic changes which continue ev...Smoking during pregnancy is a major source of fetal exposure to numerous harmful agents present in tobacco smoke. Lung development involves complex biochemical processes resulting in dramatic changes which continue even after birth. In addition to type I cells which form the blood-air barrier, type II alveolar epithelial (AE) cells have important and diverse functions related to immunological protection and stabilization of the alveolus through synthesis and secretion of the pulmonary surfactant. Apoptosis or programmed cells death is an important physiological process during lung embryogenesis and for the proper maintenance of homeostasis. Caspases are proteases that play important roles in regulating apoptosis. Caspase-3 is the key executioner caspase in the cascade of events leading to cell death by apoptosis. We explored the hypothesis that cigarette smoke extract (CSE) induces apoptosis in fetal rat lung type II AE cells by activation of caspase-3. To analyze these factors, isolated fetal rat lung type II AE cells were used. The cells were exposed to different concentrations of CSE (5%, 10% or 15%) (v/v) for 60 min. The results of the present study showed that CSE induced apoptosis in fetal rat lung type II AE cells with a significant increase (p 0.05) in caspase-3 activity and decrease in cell proliferation at CSE concentrations of 10% and 15% (v/v). These observations indicate that cigarette smoke extract induces apoptosis by activation of caspase-3 in fetal rat lung type II AE cells in a dose-dependent manner and may potentially alter the regulated development of the lung and the appearance of the surfactant-producing type II alveolar cells which are critical for the establishment of adequate gas exchange at birth.展开更多
Cytosolic free Ca([Ca]i)was measured in dissociated cerebral cells isolated from fetal rats with the fluorescent indicater fura-2. Increase in[Ca]i occurred rapidly following explsure of the cells to 50 mmol/L KCI,1...Cytosolic free Ca([Ca]i)was measured in dissociated cerebral cells isolated from fetal rats with the fluorescent indicater fura-2. Increase in[Ca]i occurred rapidly following explsure of the cells to 50 mmol/L KCI,10mol/L Bayk 8644 or 200μmol/L glutamate(Glu).[Ca]i elevated by展开更多
The rat chimera is an important animal model for the study of complex human diseases. In the present study we evaluated the chimeric potential of rat inner cell masses (ICMs) and fetal neural stem (FNS) cells. In ...The rat chimera is an important animal model for the study of complex human diseases. In the present study we evaluated the chimeric potential of rat inner cell masses (ICMs) and fetal neural stem (FNS) cells. In result, three rat chimeras were produced by day 5 (D5) Sprague-Dawley (SD) blastocysts injected with ICMs derived from day 6 (D6) and D5 Dark Agouti (DA) blastocysts; four rat chimeras had been generated by D5 DA blastocyst injected with D5 SD ICMs. For the requirement of gene modification, cultured rat inner cell mass cells were assessed to produce chimeras, but no chimeras were generated from injected embryos. The potential to generate chimeras from rFNS and transfected rFNS cells were tested, but no chimeric pups were produced. Only 2 of 41 fetuses derived from D5 DA blastocyst injection with SD LacZ transfected rFNS cells showed very low number of LacZ positive cells in the section. These results indicate that DA and SD rat ICMs arc able to contribute to chimeras, but their potential decreases significantly after culture in vitro (P〈0.05), and rFNS cells only have the potential to contribute to early fetal development.展开更多
Objective: To study the effects of MK-801, an antagonist to N-methyl-D-aspartate (NMDA) receptors, on the apoptosis of spinal cord neurons after cord injury and fend cord transplantation in rats. Methods: Wistar rats ...Objective: To study the effects of MK-801, an antagonist to N-methyl-D-aspartate (NMDA) receptors, on the apoptosis of spinal cord neurons after cord injury and fend cord transplantation in rats. Methods: Wistar rats were random- lzed into group A in which the animals were inflicted with spinal cord hemisection and treated with fetal cord transplantation and MK-801, group B in which the fats were injured with cord hemisection and beated with fend cord transplantation but no MK-80l are given and group C in which the rats received similar cord injury and the eavity in their cord was filled with gelfoam. All the rats were .killed on the lst, 3rd, 7th and 14th day after surgery respectively. The sections of the injured segment of the spinal cord were studied with TUNEL (terminal deoxynucleotidal transferase-mediated DUTP-biotin nick end labeling) and the expression of Bcl-2 was observed with immunohistochemistry. The positive cells were quantitatively analyzed with a computer image analysis system. Results: The Seventy of apoptosis of the cord neurons was in the order of group C > group B > group A (P < 0.005) while the ode of the intensity of Bcl-2 expression was grouP A > group B > group C (P < 0.05). Conclusion: Our findings indicate that fetal cord transplantation and the administration of MK-80l, an antagonist to NMDA receptors can attenuate apoptesis of the cord neurons ther spinal cold injury.展开更多
Under-nutrition as well as over-nutrition during pregnancy has been associated with the development of adult diseases such as diabetes and obesity.Both epigenetic modifications and programming of the mitochondrial fun...Under-nutrition as well as over-nutrition during pregnancy has been associated with the development of adult diseases such as diabetes and obesity.Both epigenetic modifications and programming of the mitochondrial function have been recently proposed to explain how altered intrauterine metabolic environment may produce such a phenotype.This review aims to report data reported in several animal models of fetal malnutrition due to maternal low protein or low calorie diet,high fat diet as well as reduction in placental blood flow.We focus our overview on the β cell.We highlight that,notwithstanding early nutritional events,mitochondrial dysfunctions resulting from different alteration by diet or gender are programmed.This may explain the higher propensity to develop obesity and diabetes in later life.展开更多
The aim of the present study was to develop a new animal model for use in uterine torsion, uterine ischemia-reperfusion, and fetal hypoxia studies in rats. A total of 14 pregnant rats on their 18 th-19 th gestational ...The aim of the present study was to develop a new animal model for use in uterine torsion, uterine ischemia-reperfusion, and fetal hypoxia studies in rats. A total of 14 pregnant rats on their 18 th-19 th gestational days were used. The animals were randomly divided into two groups: those undergoing the shame operation(group 1),and those in which a 360 uterine torsion was performed using a novel technique,which was corrected 6 hours later(group 2). Subsequently, seven female and seven male rat pups aged 1 month were separated from the mothers in each group. The female rats were monitored until puberty via measuring the vaginal apertures. The 1-month old male rats and the female rats on reaching puberty were decapitated and histopathological tests were performed on the dissected organs, including the cerebral, visceral and genital organs. At the end of the study, no differences were observed between the groups with regard to abortions, offspring death rates and congenital abnormalities. It was observed that the time to reach puberty in female rats born from mothers with uterine torsion was longer, but the difference was statistically insignificant. No microscopic lesions were detected in the cerebral, visceral or genital organs of the offspring. Accordingly, it was concluded that offspring of mothers with the uterine torsion were not affected, at least in the short term. It was generally concluded that this animal model is appropriate for use in uterine torsion and ischemia-reperfusion studies, but is not appropriate for fetal hypoxia studies.展开更多
Cerebral angiogenesis in the early stages after cerebral ischemia injury is essential for the recovery of nerve function,in which fetal liver kinase-1(Flk-1),as a major regulator of vasculogenesis and angiogenesis,p...Cerebral angiogenesis in the early stages after cerebral ischemia injury is essential for the recovery of nerve function,in which fetal liver kinase-1(Flk-1),as a major regulator of vasculogenesis and angiogenesis,plays a very important role.Microvessel density(MVD)was greater in an aged model group compared with the young sham operated group(P 〈 0.01).MVD and the sum of the lumen area were decreased in the aged group at 1,3,6 and 12 days following ischemia/reperfusion(I/R)injury compared with the young model group(P 〈 0.05 and P 〈 0.01,respectively).Flk-1 protein and mRNA expression was greater in the aged model group when compared with the young sham operated group(P 〈 0.01).Flk-1 protein and mRNA expression was lower in the aged group at 1,3,6 and 12 days after I/R compared with the young model group(P 〈 0.01).Flk-1 expression in aged rats attenuated rapidly,but was still maintained at relatively higher levels at 12 days following I/R in younger rats.The results suggest that angiogenesis was weakened after cerebral I/R in aged rats,and the mechanism of which might be correlated with attenuated expression of Flk-1 protein and mRNA.展开更多
基金funded by the National Natural Science Foundation of China,No.81170577
文摘From pregnancy to parturition, Sprague-Dawley rats were daily administered a low protein diet to establish a model of intrauterine growth restriction. From the 12th day of pregnancy, 300 mg/kg taurine was daily added to food until spontaneous delivery occurred. Brain tissues from normal neonatal rats at 6 hours after delivery, neonatal rats with intrauterine growth restriction, and neo- natal rats with intrauterine growth restriction undergoing taurine supplement were obtained for fur- ther experiments. The terminal deoxyribonucleotidyl transferase (TdT)-mediated biotin-16-dUTP nick-end labeling assay revealed that the number of apoptotic cells in the brain tissue of neonatal rats with intrauterine growth restriction significantly increased. Taurine supplement in pregnant rats reduced cell apoptosis in brain tissue from neonatal rats with intrauterine growth restriction. Immu- nohistochemical staining revealed that taurine supplement increased glial cell line-derived neuro- trophic factor expression and decreased caspase-3 expression in the cerebral cortex of intrauterine growth-restricted fetal rats. These results indicate that taurine supplement reduces cell apoptosis through the glial cell line-derived neurotrophic factor-caspase-3 signaling pathway, resulting in a protective effect on the intrauterine growth-restricted fetal rat brain.
基金supported by the Medical Scientific Research Foundation of Guangdong Province of China,No.A2015619
文摘Dexmedetomidine has significant neuroprotective effects. However, whether its protective effects can reduce neurotoxicity caused by isoflurane in fetal brain during the second trimester of pregnancy remains unclear. In this study, timed-pregnancy rats at gestational day 14 spontaneously inhaled 1.5% isoflurane for 4 hours, and were intraperitoneally injected with dexmedetomidine at dosages of 5, 10, 20, and 20 μg/kg 15 minutes before inhalation and after inhalation for 2 hours. Our results demonstrate that 4 hours after inhaling isoflurane, 20 μg/kg dexmedetomidine visibly mitigated isoflurane-induced neuronal apoptosis, reversed downregulation of brain-derived neurotrophic factor expression, and lessened decreased spatial learning and memory ability in adulthood in the fetal rats. Altogether, these findings indicate that dexmedetomidine can reduce neurodegeneration induced by isoflurane in fetal rats during the second trimester of pregnancy. Further, brain-derived neurotrophic factor participates in this process.
基金the Natural Science Foundation of Sichuan Educational Bureau, No. Chuanjiaoji (2001) 149-01LA40
文摘BACKGROUND: Both c-Fos protein and nitricoxide synthase (NOS) have been used as general indexes in relative research about neurons, but it is lack of reports that c-Fos protein and NOS are applied synchronously to study the neurons of hypoxic fetal rats in uterus. OBJECTIVE: To study the effect of hypoxia in uterus on the expression of c-Fos protein and NOS in neurons of cerebral cortex from fetal rats and whether Angelica sinensis has the protective effect on these neurons in hypoxia. DESIGN: Randomized control experiment.SETTING : Department of Histology and Embryology, Luzhou Medical College.MATERIALS : Twelve adult female Wistar rats in oestrum and 1 male Wistar rat with bodymass from 220 to 250 g were chosen. Parenteral solution of Angelica sinensis mainly contained angelica sinensis, 10 mL/ampoule, was provided by Department of Agent of the Second Hospital Affiliated to Hubei Medical University (batch number: 01062310). METHODS : This experiment was completed in the Department of Histology and Embryology of Luzhou Medical College from September 2003 to June 2004. ①Twelve adult female Wistar rats in oestrum and 1 male Wistar rat were housed in one rearing cage. Vaginal embolus was performed on conceive female rat at 8: 00 am next day. On the 15^th conceiving day, all conceiving rats were divided randomly into three groups: control group, hypoxia group and Angelica group with 4 in each group. Rats in hypoxia group and Angelica group were modeled with hypotonic hypoxia in uterus. Angelica group: Rats were injected with 8 mL/kg Angelica sinensis injection through caudal veins before hypoxia. Hypoxia group: Rats were injected with the same volume of saline. Control group: Rats were not modeled and fed with normal way. ② Twenty embryos of rats were chosen randomly from each group and then routinely embedded in paraffin. Paraffin sections were cut from the brain of embryos to anterior fontanelle. Double-label staining was used to detect the expression of nNOS and c-Fos in neurons of cerebral cortex from embryos of rats. OLYMPUS Bx-50 microscope was used to observe sections and DP12 digit camera was also used under 400 times to detect types of cells. Under microscope, the number of c-Fos, NOS, c-Fos/NOS positive neurons in cerebral cortex from embryos of rats were counted in 2 fields with magnification of 400 in one section per animal. ③ The data in experiments were analyzed by one-way analysis of variance (ANOVA) followed by q test. MAIN OUTCOME MEASURES: ① Results of immunohistochemical double-label staining of c-Fos/NOS from cerebral cortex; ② Comparison of amount immunohistochemical double-label staining of c-Fos/NOS positive cells from cerebral cortex. RESULTS:① The positive NOS cells and c-Fos/NOS cells in the three groups were mainly distributed in cerebral cortex, but positive c-Fos neurons were not observed. ② Positive NOS cells and c-Fos/NOS cells in hypoxia group were more than those in control group (76.55±12.02, 50.45±10.39; 33.35±7.42, 26.35±6.67, P 〈 0.05), but those in Angelica group were less than those in hypoxia group (51.70±9.82, 35.65±8.37, P 〈 0.05). CONCLUSION: Hypoxia can stimulate the increase of expression of c-Fos protein and NOS in neurons of cerebral cortex. However, Angelica sinensis can decrease this expression so as to play a protective role in cerebral neurons of hypoxic fetal rats.
基金Natural Science Foundation of China (NO.81373703 NO. 81674042)Basic research project of natural science in shaanxi province - major basic research project (NO. 2017zdjc-15)
文摘Objective: To establish a simple, effective and high-purity primary culture method for fetal rat hippocampalneurons. Methods: Wistar rats of gestational age 18 days were taken and the brain tissue was separated under themicroscope. Single neuronal cells were obtained by digestion with Brain Dissociation Kit, and then were seeded incell plates to observe the basic morphologic structure after 24h, 3d, and 5d. Immunofluorescence of microtubuleassociated protein 2 was applied to assess cell purity of the culture. Results: The hippocampal neurons obtained inthis culture method are in good condition and grow vigorously. On the 7th day after culture, the purity of neuronswas up to 99.62%. Conclusion: The method is simple and effective for obtaining the high-purity and stableneurons.
文摘Objective To observe the spatial and temporal distribution of collagen in fetal and adult rats wounds. Methods The organization of collagen deposition in fetal and adult rats skin wounds were observed by using van Gieson stain. The methods of immunohistochemistry and in situ hybridization were applied to examine collagen type Ⅰ and Ⅲ peptide and mRNA localization at serial time point during wound healing. Results Collagen type Ⅰ and Ⅲ were present in wounds of both fetal and adult rats, but the timing and pattern of collagen deposition varied. In the fetus, collagen wes detected by 48h postwounding (PW), but uns not present in the adult wounds until 5d PW. N in situ hybridization, signals in the area of the fetal wound were clearly greater and with increased number of cells as compered to that in the adjacent unwounded tissue. Adult rat wounds had evidence in increased signals of procollagen type Ⅰ and Ⅲ production by wound fibroblasts on day 5. Collagen deposited and wes arranged in reticular pattern as that of the nounal in fetal wounds. While in the adult wound, collagen deposited in the fashion of course bundles. bundles Conclusion Fetal rat wounds appeared to produce collagen mainly by an increased number offibroblasts in the area of the wound. In contrast, adult rat wounds underwent fibroblast migration and induction of procollagen mRNA synthesis. Our results Suggest that the deposition of collagen type Ⅰ and Ⅲ is regulated by their gene expression. Chllagen type Ⅲ plays an important role in the arrangement of collagen depoition.
文摘Smoking during pregnancy is a major source of fetal exposure to numerous harmful agents present in tobacco smoke. Lung development involves complex biochemical processes resulting in dramatic changes which continue even after birth. In addition to type I cells which form the blood-air barrier, type II alveolar epithelial (AE) cells have important and diverse functions related to immunological protection and stabilization of the alveolus through synthesis and secretion of the pulmonary surfactant. Apoptosis or programmed cells death is an important physiological process during lung embryogenesis and for the proper maintenance of homeostasis. Caspases are proteases that play important roles in regulating apoptosis. Caspase-3 is the key executioner caspase in the cascade of events leading to cell death by apoptosis. We explored the hypothesis that cigarette smoke extract (CSE) induces apoptosis in fetal rat lung type II AE cells by activation of caspase-3. To analyze these factors, isolated fetal rat lung type II AE cells were used. The cells were exposed to different concentrations of CSE (5%, 10% or 15%) (v/v) for 60 min. The results of the present study showed that CSE induced apoptosis in fetal rat lung type II AE cells with a significant increase (p 0.05) in caspase-3 activity and decrease in cell proliferation at CSE concentrations of 10% and 15% (v/v). These observations indicate that cigarette smoke extract induces apoptosis by activation of caspase-3 in fetal rat lung type II AE cells in a dose-dependent manner and may potentially alter the regulated development of the lung and the appearance of the surfactant-producing type II alveolar cells which are critical for the establishment of adequate gas exchange at birth.
文摘Cytosolic free Ca([Ca]i)was measured in dissociated cerebral cells isolated from fetal rats with the fluorescent indicater fura-2. Increase in[Ca]i occurred rapidly following explsure of the cells to 50 mmol/L KCI,10mol/L Bayk 8644 or 200μmol/L glutamate(Glu).[Ca]i elevated by
文摘The rat chimera is an important animal model for the study of complex human diseases. In the present study we evaluated the chimeric potential of rat inner cell masses (ICMs) and fetal neural stem (FNS) cells. In result, three rat chimeras were produced by day 5 (D5) Sprague-Dawley (SD) blastocysts injected with ICMs derived from day 6 (D6) and D5 Dark Agouti (DA) blastocysts; four rat chimeras had been generated by D5 DA blastocyst injected with D5 SD ICMs. For the requirement of gene modification, cultured rat inner cell mass cells were assessed to produce chimeras, but no chimeras were generated from injected embryos. The potential to generate chimeras from rFNS and transfected rFNS cells were tested, but no chimeric pups were produced. Only 2 of 41 fetuses derived from D5 DA blastocyst injection with SD LacZ transfected rFNS cells showed very low number of LacZ positive cells in the section. These results indicate that DA and SD rat ICMs arc able to contribute to chimeras, but their potential decreases significantly after culture in vitro (P〈0.05), and rFNS cells only have the potential to contribute to early fetal development.
文摘Objective: To study the effects of MK-801, an antagonist to N-methyl-D-aspartate (NMDA) receptors, on the apoptosis of spinal cord neurons after cord injury and fend cord transplantation in rats. Methods: Wistar rats were random- lzed into group A in which the animals were inflicted with spinal cord hemisection and treated with fetal cord transplantation and MK-801, group B in which the fats were injured with cord hemisection and beated with fend cord transplantation but no MK-80l are given and group C in which the rats received similar cord injury and the eavity in their cord was filled with gelfoam. All the rats were .killed on the lst, 3rd, 7th and 14th day after surgery respectively. The sections of the injured segment of the spinal cord were studied with TUNEL (terminal deoxynucleotidal transferase-mediated DUTP-biotin nick end labeling) and the expression of Bcl-2 was observed with immunohistochemistry. The positive cells were quantitatively analyzed with a computer image analysis system. Results: The Seventy of apoptosis of the cord neurons was in the order of group C > group B > group A (P < 0.005) while the ode of the intensity of Bcl-2 expression was grouP A > group B > group C (P < 0.05). Conclusion: Our findings indicate that fetal cord transplantation and the administration of MK-80l, an antagonist to NMDA receptors can attenuate apoptesis of the cord neurons ther spinal cold injury.
基金Supported by the European Commission (FOOD-CT-2005007036)the Parthenon Trust (London,UK)+1 种基金the Belgian Fonds National de la Recherche Scientifiquethe Belgian Fonds pour la Recherche dans l’Industrie et l’Agriculture
文摘Under-nutrition as well as over-nutrition during pregnancy has been associated with the development of adult diseases such as diabetes and obesity.Both epigenetic modifications and programming of the mitochondrial function have been recently proposed to explain how altered intrauterine metabolic environment may produce such a phenotype.This review aims to report data reported in several animal models of fetal malnutrition due to maternal low protein or low calorie diet,high fat diet as well as reduction in placental blood flow.We focus our overview on the β cell.We highlight that,notwithstanding early nutritional events,mitochondrial dysfunctions resulting from different alteration by diet or gender are programmed.This may explain the higher propensity to develop obesity and diabetes in later life.
文摘The aim of the present study was to develop a new animal model for use in uterine torsion, uterine ischemia-reperfusion, and fetal hypoxia studies in rats. A total of 14 pregnant rats on their 18 th-19 th gestational days were used. The animals were randomly divided into two groups: those undergoing the shame operation(group 1),and those in which a 360 uterine torsion was performed using a novel technique,which was corrected 6 hours later(group 2). Subsequently, seven female and seven male rat pups aged 1 month were separated from the mothers in each group. The female rats were monitored until puberty via measuring the vaginal apertures. The 1-month old male rats and the female rats on reaching puberty were decapitated and histopathological tests were performed on the dissected organs, including the cerebral, visceral and genital organs. At the end of the study, no differences were observed between the groups with regard to abortions, offspring death rates and congenital abnormalities. It was observed that the time to reach puberty in female rats born from mothers with uterine torsion was longer, but the difference was statistically insignificant. No microscopic lesions were detected in the cerebral, visceral or genital organs of the offspring. Accordingly, it was concluded that offspring of mothers with the uterine torsion were not affected, at least in the short term. It was generally concluded that this animal model is appropriate for use in uterine torsion and ischemia-reperfusion studies, but is not appropriate for fetal hypoxia studies.
基金the National Natural Science Foundation of China, No. 30371812the Henan Provincial Science Fund for Distinguished Young Scholars, No. 0612000700
文摘Cerebral angiogenesis in the early stages after cerebral ischemia injury is essential for the recovery of nerve function,in which fetal liver kinase-1(Flk-1),as a major regulator of vasculogenesis and angiogenesis,plays a very important role.Microvessel density(MVD)was greater in an aged model group compared with the young sham operated group(P 〈 0.01).MVD and the sum of the lumen area were decreased in the aged group at 1,3,6 and 12 days following ischemia/reperfusion(I/R)injury compared with the young model group(P 〈 0.05 and P 〈 0.01,respectively).Flk-1 protein and mRNA expression was greater in the aged model group when compared with the young sham operated group(P 〈 0.01).Flk-1 protein and mRNA expression was lower in the aged group at 1,3,6 and 12 days after I/R compared with the young model group(P 〈 0.01).Flk-1 expression in aged rats attenuated rapidly,but was still maintained at relatively higher levels at 12 days following I/R in younger rats.The results suggest that angiogenesis was weakened after cerebral I/R in aged rats,and the mechanism of which might be correlated with attenuated expression of Flk-1 protein and mRNA.