人参皂苷Rg1、 Re对大鼠胚胎脑发育及谷胱甘肽过氧化物酶基因表达的影响

目的:观察人参皂苷Rg1、 Re对SD雌性大鼠胚胎脑发育及谷胱甘肽过氧化物酶(GPx)基因表达的影响.方法:选用全胚胎体外培养方法,随机分为对照组、人参皂苷Rg1 (10、 45和90μg/ml)组和Re (10、 45和90μg/ml)组,采用半定量RT-PCR分析人参皂苷Rg1和Re对GPx基因表达的影响.结果:人参皂苷Rg1组(10、 45和90μg/ml)对胚胎中脑和后脑的生长发育检测值差异有统计学意义,而胚胎脑长度和前脑的生长发育检测值差异无统计学意义;与对照组比较,Re (10、 45和90μg/ml)组胚胎脑发育的形态学检测无影响.RT-PCR结果显示,Rg1组(10、 45和90μg/ml) cGPx, pGPx和phGPx mRNAs的表达水平与对照组比较均无统计学意义;Re组(10、 45和90μg/ml) cGPx和phGPx mRNA的表达水平与对照组比较均无统计学意义,而pGPx mRNA的表达水平在3种剂量的人参皂苷Re作用后都增强,且在浓度10和45μg/ml时有统计学意义.结论:一定剂量的Rg1能促进胚胎脑的发育,一定剂量的Re能明显增强胚胎脑pGPx mRNA的表达.     

Dynamics of LPO products and oxidative modification of proteins in human brain during postnatal development

Opposite changes in the content of LPO products and products of oxidative modification of proteins were detected in human brain structures in the course of postnatal development. A clear-cut ontogenetic reduction of LPO products was observed in field 17 of the cortex, archicortex structures, and in the hypothalamus. Age-specific increase in the levels of products of oxidative modification of proteins was recorded in all compartments of the brain; it peaked by the age of 12–21 years and was most pronounced (4–6-fold) in the visual cortex, hippocampus, diencephalic and pontobulbar compartments of the brain. __________ Translated from Byulleten’ Eksperimental’oi Biologii i Meditsiny, Vol. 144, No. 8, pp. 159–166, August, 2007     

Uptake and subcellular distribution of 65zinc in brain structures during the postnatal development of the rat

The uptake ratio of 65zinc into the postnatally developing hippocampal formation, cerebellum and remainder of the brain showed only minor differences, whilst following subcellular fractionation a marked decrease in 65zinc uptake from postnatal day 15 to adulthood was found in nuclear sediments (hippocampal formation 44.3%, cerebellum 27.5%), along with an increase in synaptosomal fractions on the hippocampal formation by 55.4% and of the cerebellum by 37.1%. The shift of zinc out of the perikarya into terminal fields during the postnatal development without substantial alterations of the net zinc content is supposed to be a consequence of a functional relation of zinc to synaptic transmission processes.     

Nnat基因在大鼠脑发育过程中表达的初步研究

目的:观察Nnat基因在大鼠脑发育过程中基因表达的变化规律,藉以探讨Nnat在神经系统发育过程中的作用。方法:采用半定量RT-PCR法分析出生前后大鼠脑内Nnat表达水平的变化,Western blot检测Nnat蛋白的表达。结果:在大鼠胚胎第9 d(E9)脑内Nnat mRNA开始表达,但表达量较低,以后其表达量逐渐升高,出生前有轻微下调。出生后大鼠的不同脑区Nnat mRNA的表达量都呈现下降趋势,60 d时达到较低的水平。Nnat蛋白在不同脑区都具有表达,但不同亚型蛋白量的相对比例不同。结论:Nnat基因在胚胎期及出生后大鼠脑内的表达量与中枢神经系统发育及分化过程的时间上有一定的同步性,提示Nnat的作用可能与神经元分化的调节有关。     

大鼠生后视网膜发育过程中Nurr1与TH的相关关系研究

目的:观察核受体相关因子1(nuclear receptor-related factor 1,Nurr1)与多巴胺能神经细胞特异性标记物酪氨酸羟化酶(TH)在生后大鼠视网膜发育过程中的表达变化,探明Nurr1与视网膜多巴胺能神经元的相关关系。方法:石蜡包埋组织切片,免疫组织化学双重标记。结果:Nurr1在视网膜发育过程中的表达出现了显著的动态变化,Nurr1阳性产物主要表达在内核层细胞,生后3～7 d达到高峰,之后随着细胞的成熟阳性表达又逐渐减少,成熟的视网膜组织内仅见少量Nurr1阳性细胞,在视网膜神经细胞从幼稚到成熟的分化过程中仅见个别TH阳性细胞。Nurr1与TH的免疫组化双标结果显示两蛋白可以共表达在同一细胞中,但众多的Nurr1阳性细胞不表达TH。结论:Nurr1在大鼠视网膜多巴胺能神经细胞及非多巴胺能神经细胞从幼稚到成熟的分化过程中可能具有重要的调控作用。     

Prox1 expression patterns in the developing and adult murine brain.

Prox1, a homeobox gene related to the Drosophila gene prospero, is necessary for retina, lens, liver, pancreas, and lymphatics development. However, not much is yet known about Prox1 expression during central nervous system development. Here we provide a detailed analysis of Prox1 mRNA and protein expression during prenatal and postnatal murine brain development. Prenatally, Prox1 is expressed in the subventricular zone or in early differentiating regions of the brain. At these stages, Prox1 mRNA, but not Prox1 protein, was also detected in several regions of the prethalamus and hypothalamus. At an early postnatal stage, Prox1 expression is mainly detected in several nuclei of the thalamus, the cerebellum, and the hippocampus. In adulthood, Prox1 expression remains only in the hippocampus and cerebellum. These complex patterns of expression suggest that Prox1 activity is differentially required during brain development and adulthood.     

Changes in catecholamine concentrations in the hypothalamus and region of the midbrain raphe in male and female rats during postnatal development

To investigate possible sex differences in central catecholaminergic systems, the concentrations of dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC) were measured by high-performance liquid chromatography with electrochemical detection in the hypothalamus-preoptic area (H-POA) and midbrain raphe (MR) region of male and female rats throughout postnatal development. Other than a small but significant sex difference in DA concentration in the MR at 36 h (higher in females), the results showed that there were no sex differences in the concentrations of DA or DOPAC at any age in either brain region. The developmental profiles of the concentrations of DA and DOPAC showed that DAergic systems in the H-POA are immature at birth, with concentrations increasing steadily until 80 days of age, but in the MR concentrations reach a maximum at 20 days of age; a situation which is perhaps a reflection of differing monoamine metabolism in the two areas.     

The distribution of neuron‐specific gene family member 1 in brain and germ cells: Implications for the regulation of germ‐line development by brain

Vesicular acidification at early endosomes dissociates endocytosed receptor‐ligand complexes. The ligands, receptors, or both are then directed to late endosomes for degradation or recycled back to the plasma membrane. Of neuron‐specific gene (NSG) family members, early endosomal protein neuron‐specific gene family member 1 (NSG1) is the most important in receptor recycling. In this study, we characterized chicken NSG1 (cNSG1). We found several functional sites related to endocytotic machinery in cNSG1 that were highly conserved with most other vertebrate NSG1 proteins. We examined the tissue and duration specificity and the temporal and spatial patterns of cNSG1 expression. cNSG1 expression was preferentially located in all regions of the brain, neuroendocrine glands, and spinal cord. Unexpectedly, cNSG1 expression was strongly detected during male and female germ‐line development. Expression of NSG1 in two apparently unrelated cell types such as neurons and germ cells suggests NSG1 roles in neurons and germ‐cells chemotaxis and endocytotic machinery. Developmental Dynamics 240:850–861, 2011. © 2011 Wiley‐Liss, Inc.     

出生前后胆碱乙酰转移酶在大鼠脑内定位的研究

为探讨大鼠胚胎及生后发育期间脑内胆碱乙酰转移酶(choline acetyltransferase,ChAT)的变化规律,本研究采用免疫组织化学方法,观察了胚胎和生后大鼠脑内ChAT样(ChAT-like immunoreactive,ChAT-LI)神经元表达的数量和灰度值。结果显示:ChAT-LI产物主要表达在细胞体、纤维及其末梢。ChAT-LI神经元最先在胚胎第12d(embryonic day12,E12),出现于端脑;E14时可见于隔核和中缝核;E16时内嗅区出现ChAT-LI神经元;E18时出现于视前区节细胞层;E20时,海马内部可见部分ChAT-LI纤维;生后第0d(postnatal day0,P0),少量带有生长锥的ChAT-LI纤维出现于海马;P5时,海马内出现ChAT-LI神经元,且ChAT-LI纤维进一步增加;P10时,海马、内嗅区和穹隆等结构中都可见ChAT-LI神经元胞体及纤维。上述结果提示:胆碱能神经元在出生前后的大鼠脑内,尤其是在海马记忆回路的发育过程中存在一定的变化规律,它们可能是学习记忆等功能的结构基础。     

Common genetic variation in the GAD1 gene and the entire family of DLX homeobox genes and autism spectrum disorders

Biological and positional evidence supports the involvement of the GAD1 and distal‐less homeobox genes (DLXs) in the etiology of autism. We investigated 42 single nucleotide polymorphisms in these genes as risk factors for autism spectrum disorders (ASD) in a large family‐based association study of 715 nuclear families. No single marker showed significant association after correction for multiple testing. A rare haplotype in the DLX1 promoter was associated with ASD (P‐value = 0.001). Given the importance of rare variants to the etiology of autism revealed in recent studies, the observed rare haplotype may be relevant to future investigations. Our observations, when taken together with previous findings, suggest that common genetic variation in the GAD1 and DLX genes is unlikely to play a critical role in ASD susceptibility. © 2010 Wiley‐Liss, Inc.     

Feasibility of neurochemically profiling mouse embryonic brain and its development in utero using 1H MRS at 14.1 T

We aimed to evaluate the feasibility of neurochemical profiling of embryonic mouse brain developments in utero and to seek potential in vivo evidence of an energy shift in a mitochondrial pyruvate carrier 1 (MPC1) deficient mouse model. C57BL/6 embryonic mouse brains were studied in utero by anatomical MRI and short echo localized proton (¹H) MRS at 14.1 T. Two embryonic stages were studied, the energy shift (e.g., embryonic day 12.5–13, E12.5–13) and close to the birth (E17.5–18). In addition, embryonic brains devoid of MPC1 were studied at E12.5–13. The MRI provided sufficient anatomical contrasts for visualization of embryonic brain. Localized ¹H MRS offered abundant metabolites through the embryonic development from E12.5 and close to the birth, e.g., E17.5 and beyond. The abundant neurochemical information at E12.5 provided metabolic status and processes relating to cellular development at this stage, i.e., the energy shift from glycolysis to oxidative phosphorylation, evidenced by accumulation of lactate in E12.5–13 embryonic brain devoid of MPC1. The further evolution of the neurochemical profile of embryonic brains at E17.5–18 is consistent with cellular and metabolic processes towards the birth. Localized ¹H MRS study of embryonic brain development in utero is feasible, and longitudinal neurochemical profiling of embryonic brains offers valuable insight into early brain development.     

类固醇受体辅助活化因子-1在成年雄性大鼠脑内的表达研究

目的研究类固醇受体辅助活化因子（steroid receptor coactivator-1,SRC-1）在成年雄性大鼠脑内的表达。方法采用硫酸镍铵增强显色的免疫组化技术研究大鼠海马内SRC-1的表达情况。结果SRC-1主要在细胞核内表达,但是在某些核团,尤其是与运动调节有关的核团,可以在细胞核外表达,如胞浆、胞膜甚至突起内。最强表达见于基底前脑的斜角带垂直部、下丘脑弓状核与网状外侧核;高水平的表达见于前嗅核、海马、丘脑和下丘脑部分核团、桥核、脚间核与小脑浦肯野细胞;中等水平的表达见于大部分大脑皮质结构和杏仁复合体以及丘脑,低水平的表达见于中脑、脑桥和延髓大部份。结论SRC-1在成年雄性大鼠脑内的表达比较广泛,可能参与了对多种重要脑功能的调节,如学习记忆、神经干细胞分化发育、神经内分泌与神经免疫、生殖、信息整合与感觉和运动。另外,在大部分脑区SRC-1可能以经典的基因型方式发挥作用,但是,在部分核团也能以通过第二信使的非基因型方式发挥作用。     

Increasing frequency of occurrence of tuft cells in the main excretory duct during postnatal development of the rat submandibular gland

Tuft cells, a widespread cell type that is present in the mucosal epithelia of hollow organs, including the main excretory duct (MED) epithelia of the rat salivary gland, are well documented morphologically. However, studies of their development are few. The purpose of the present study was to examine the perinatal and postnatal development of tuft cells in the main excretory duct of the rat submandibular gland. Main excretory ducts of the submandibular gland were obtained from five male Wistar rats at the ages of 0, 1, 7, 14, 17, 21, 23, 28, and 56 postnatal days and were prepared for scanning and transmission electron microscopy. The tuft cells, which are distinguished easily by their long microvilli protruding into the lumen, were recognizable first at 17 postnatal days. They showed a remarkable increase in number between 3 and 4 postnatal weeks. The percentages of tuft cells were 0.4% at 17 postnatal days and 0.8% at 3 postnatal weeks. The number of tuft cells represented approximately 5% of the total epithelial cells by 4 postnatal weeks. There was a significant difference between 3 and 4 postnatal weeks (P < 0.01). The microvilli of the tuft cells at the time of weaning had almost the same width as in the adult, but they were shorter. Microfilaments extending from the tips of the microvilli and microtubules and many electron-lucent vesicles in the supranuclear cytoplasm also were observed. These results indicate that tuft cells appeared in the MED of the submandibular gland during weaning and had abundant vesicles in their apical cytoplasm. Anat. Rec. 252:276–280, 1998. © 1998 Wiley-Liss, Inc.     

脑脊髓损伤大鼠局部Th1/Th2细胞相关因子的表达及意义

目的 分析大鼠急性脑脊髓性损伤后脑脊髓中Th1和Th2细胞相关因子的表达水平,探讨其在持续性二次损伤中可能的作用.方法 制备SD大鼠急性脑脊髓性损伤模型,随机分为损伤组和脂多糖(LPS)处理组,各组又分别对脑和脊髓进行实验处理.用荧光定量PCR分别检测不同组别大鼠脑脊髓中Th1和Th2细胞相关因子,并进行相关性分析.结果 与对照组相比,损伤和LPS处理的脑组织Th1细胞相关的细胞因子IFN-γ表达明显增高(P＜0.05),而T-bet的表达并无明显改变;在损伤和LPS处理的脊髓中,IFN-γ和转录因子T-bet、HLX的表达均显著升高(P＜0.05).无论是脊髓损伤组还是LPS处理组,细胞因子IL-4和转录因子GATA3均与对照组无异,呈低表达状态.结论 脑脊髓损伤后呈现不同程度的Th1细胞相关因子上调,尤以可溶性的细胞因子IFN-γ为显著,脊髓损伤时出现T-bet与HLX表达上调.     

Alternative splicing of the FMR1 gene in human fetal brain neurons

The alternative splicing expression of the FMR1 gene was reported in several human and mouse tissues. Five regions of FMR1 gene can be alternatively spliced, but the combination of them has not been investigated fully. We reported here the analysis of alternative splicing pattern of the FMR1 gene in cultured fetal human neurons, using a RT-PCR and cloning strategy. Eleven splicing types were cloned and different isoforms were not equally represented. The dominant isoform represents nearly 40%, and the other isoforms were relatively rare. One isoform has a different carboxyl-terminus. Most of the alternative spliced regions appear hydrophilic; thus, they may locate on the surface of the FMR1 protein. © 1996 Wiley-Liss, Inc.     

Changes in glycoconjugates revealed by lectin staining and stage-specific embryonic antigen-1 immunostaining in hamster submandibular glands during the postnatal period

Lectin binding and stage-specific embryonic antigen-1 (SSEA-1) immunoreactivity were studied in the developing submandibular glands of young Syrian golden hamsters (Mesocricetus auratus) from postnatal day 1 (the day of birth) to day 28. The submandibular glands were fixed in a solution containing 6% mercuric chloride, 1% sodium acetate, and 0.1% glutaraldehyde (HgCl₂-G) or 4% paraformaldehyde (4P), and embedded in paraffin. Sections from HgCl₂-G fixation were stained with three lectin-peroxidase conjugates: peanut agglutinin (PNA), Ulex europeus I agglutinin (UEA I), and wheat germ agglutinin (WGA). Sections from the 4P-fixed tissues were immunostained with monoclonal antibodies against SSEA-1, sialyl SSEA-1 and fucosyl SSEA-1. On the day of birth, the terminal unit of the submandibular gland was composed of fetal type secretory cells and proacinar cells. The secretory cells were PNA, UEA I, and WGA positive. The number of secretory terminal tubule cells decreased rapidly, and lectin-positive secretory cells were replaced by adult secretory cells that did not show PNA or UEA I stainings but were weakly positive for WGA. Fetal secretory cells were positively immunostained for SSEA-1 and sialyl SSEA-1, and immature ductal cells were stained for fucosyl SSEA-1. The positive stainings disappeared with regression of the fetal epithelial cells. Hence, modulation of glycoconjugate expression in the submandibular glands, which reflects changes in secretory cells from the fetal type to adult type during postnatal development, is revealed by lectin staining and immunostaining for SSEA-1 and related antigens.