Ontogenetic development of septal nuclei in the rat

Summary Prenatal development of septal cell groups was studied in the rat on samples taken daily from the 14th day of gestation until birth. Coronal serial sections of brains were prepared in which the topography coordinates of septal nuclei were determined, their section profiles measured and their volumes calculated. The rat septum begins to develop on embryonic days 14–15. First the individual neurons start to differentiate, then cell groups characteristic for the adult are formed between days 14 and 17, which is followed by the delineation of nuclei. The only exception is the anterior subdivision of the lateral septal nucleus where the formation of the nucleus precedes the differentiation of its constituent cells. The individual nuclei start to develop at different times defined by a medio-lateral gradient of cell migration. By embryonic day 20 the formation of the nuclei can be considered as complete: all septal nuclei and their subdivisions are to be recognized and distinguished from each other.Abbreviations CA Anterior commissure - CC corpus callosum - CH hippocampal commissure - dm dorsal septal nucleus, magnocellular part - dp dorsal septal nucleus, parvocellular part - f fimbrial septal nucleus - FI fimbria septi - FX fornix - H hippocampal rudiment - i intermediate septal nucleus - l lateral septal nucleus - la lateral septal nucleus, anterior part - ld lateral septal nucleus, dorsal part - lv lateral septal nucleus, ventral part - md medial septal nucleus, dorsal part - mv medial septal nucleus, ventral part - NE neuroepithelium - ni bed nucleus of the commissura fornicis - po median preoptic nucleus - sfo subfornical organ - t triangular septal nucleus - td nucleus of the diagonal tract (Broca) - VL lateral ventricle     

The effect of aging on the structure and function of liver messenger RNA

The size of the poly(A) segment of poly(A)+RNA extracted from hepatocytes isolated from 4- to 30-month-old rats was determined using polyacrylamide-agarose gel electrophoresis. The average size of the poly(A) segment isolated from newly synthesized poly(A)+RNA was 150 nucleotides, and the average size of the poly(A) segment isolated from the steady state pool of cytoplasmic poly(A)+RNA was 70 nucleotides. No significant age related change in either the size or the heterogeneity of the newly synthesized poly(A) segment was found. The translational activity of poly(A)+RNA isolated from livers of 4- to 30-month-old rats was determined using wheat germ extract and rabbit reticulocyte lysate cell-free systems. No age-related change in the translational activity of the poly(A)+RNA was observed. The effect of aging on the cap structure was also studied by measuring the inhibition of cell-free translation by 7-methyl guanosine-5'-monophosphate. No age-related change in the sensitivity of the poly(A)+RNA preparations to inhibition of translation by 7-methyl guanosine-5'-monophosphate was observed. Therefore, the results of this study demonstrate that no major age-related change occurs in the structure of the poly(A) segment, the translational activity, or the cap structure of poly(A)+RNA from rat liver.     

Identification of messenger RNA of fetoplacental source in maternal plasma of women with normal pregnancies and pregnancies with intrauterine growth restriction

Objective:

to quantify placenta-specific RNA in plasma of women carrying foetuses with intrauterine growth restriction and pregnant women with normal pregnancies.

Methods:

8 pregnant women with foetuses with intrauterine growth restriction were studied as well as 18 women with uncomplicated pregnancies in the third pregnancy trimester. Total free RNA was quantified in maternal plasma by spectrophotometry and the gene expression of hPL (Human Placental Lactogen) at the messenger RNA level through technical Real Time-Chain Reaction Polymerase.

Results:

plasma RNA of fetoplacental origin was successfully detected in 100% of pregnant women. There were no statistically significant differences between the values of total RNA extracted from plasma (p= 0.5975) nor in the messenger RNA expression of hPL gene (p= 0.5785) between cases and controls.

Conclusion:

messenger RNA of fetoplacental origin can be detected in maternal plasma during pregnancy.     

Ribosomal and translatable messenger RNA of Eimeria tenella

RNA from oocysts of Eimeria tenella was purified into poly(A)--RNA and poly(A)+-RNA fractions with affinity chromatography on oligo(dT)-cellulose. Gel electrophoresis, under denaturing conditions of the poly(A)--RNA fraction revealed two major RNAs with molecular weights of 1.27 and 0.65 X 10(6). The values for these components not only represent the ribosomal RNAs of this species; but they also resemble the molecular sizes of the non-mRNAs of many other lower eukaryotes. In vitro translation assays with a cell-free wheat germ system showed that the level of translatable mRNA in the poly(A)--RNA fraction was negligible. Virtually all the translatable mRNA in E. tenella was polyadenylated, that is, it contained poly(A)-tracts with more than 15 adenylate residues. Consequently some of the key components of the protein translational machinery of this organism are eukaryotic in nature.     

胰岛淀粉样多肽对阿尔茨海默病小鼠脑组织中LncRNA和mRNA表达谱的影响

目的:探讨胰岛淀粉样多肽（IAPP）对阿尔茨海默病（AD）小鼠脑组织中长链非编码RNA（LncRNA）和信使RNA（mRNA）表达谱的影响。方法:选取7月龄雄性APP/PS1转基因AD模型小鼠10只,体质量20～30 g。将AD模型小鼠按数字表法随机分为IAPP干预组和对照组,每组5只。IAPP干预组小鼠腹腔内注射0....     

Cholecystokinin and tyrosine hydroxylase messenger RNAs in neurons of rat mesencephalon: peptide/monoamine coexistence studies using in situ hybridization combined with immunocytochemistry

Summary The cellular localization of neurons expressing cholecystokinin (CCK) and tyrosine hydroxylase (TH) mRNAs was analysed in rat ventral mesencephalon using in situ hybridization techniques with both complementary DNA and synthetic oligonucleotide probes. Cell bodies distributed throughout the substantia nigra, ventral tegmental area, interfascicular nucleus, midline raphe nuclei, and central and ventral periaqueductal grey matter were found to contain CCK mRNA or TH mRNA as indicated by high densities of grains overlying the perikarya. The in situ hybridization technique was combined with immunocytochemistry on the same tissue section to localize the peptide or enzyme within its respective mRNA-containing somata. In addition, the presence of TH immunoreactivity was demonstrated within cell bodies labeled for CCK mRNA and immunostaining for CCK was detected within TH mRNA-containing neurons. In the medial geniculate nucleus a strong labeling for CCKmRNA was observed, in spite of the fact that so far no CCK-like immunoreactivity has been demonstrated in perikarya in this nucleus. The specificity of the probes was verified by RNA blot hybridization. These results confirm recent double-labeling immunocytochemical studies and further characterize the coexistence of CCK and TH at the level of their mRNAs as well as their post-translational products in a large population of mesencephalic dopamine neurons known to project to forebrain areas.     

The impact of prenatal stress on basal nociception and evoked responses to tail-docking and inflammatory challenge in juvenile pigs

The consequences of tail-docking (at 2-4 days) and prenatal stress (maternal social stress during the 2nd third of pregnancy) on baseline nociceptive thresholds and responses to acute inflammatory challenge were investigated in juvenile pigs in two studies. Nociceptive thresholds were assessed on the tail root and on the hind foot using noxious mechanical and cold stimulation before and after acute inflammatory challenge by intradermal injection of 30 μg capsaicin (study 1) or 3% carrageenan (study 2) into the tail root. Four groups of 8 (study 1, n = 14-16 pigs/treatment) or 5 (study 2, n = 6 pigs/treatment/sex) week-old pigs were exposed to the main factors: maternal stress and treatment (docked vs. intact tails). In study 1, tail docking did not significantly alter thresholds to noxious mechanical stimulation, whilst prenatally stressed pigs had significantly higher baseline thresholds to noxious mechanical stimulation on the tail root and on the hind foot than unstressed pigs, whether tail-docked or intact. Capsaicin injection induced localised mechanical allodynia around the tail root in all treatment groups, but had no effect on noxious plantar mechanical responses; however prenatally stressed offspring exhibited significantly attenuated response thresholds to capsaicin compared to controls. In study 2 tail docking did not alter thresholds to either mechanical or noxious cold stimulation. Baseline response durations to noxious cold stimulation of the tail root were significantly shorter in both sexes of prenatally stressed pigs, whilst male but not female prenatally stressed pigs exhibited significantly higher baseline thresholds to mechanical stimulation than controls, although results in female pigs tended towards significance. Carrageenan injection into the tail root induced localised mechanical and cold allodynia in all treatment groups, effects that were attenuated in prenatally stressed pigs. Collectively, these findings indicate that prenatal stress can induce long-term alterations in nociceptive responses, manifest as a reduced sensitivity to noxious mechanical and cold stimulation and evoked inflammatory allodynia. Neonatal tail-docking does not lead to long-term alterations in nociception in pigs.     

The pattern of synthesis and distribution of membrane bound RNA in brain synaptosomes

Summary The pattern of RNA synthesis and its distribution in subcellular fractions of goldfish brain was studied using uridine-5H³ as the precursor. About 14% of the total RNA synthesized was found to be associated with the synaptosomal fraction after a 3 hr labelling time. The sedimentation characteristics of this RNA was compared with that of the nuclear and cytoplasmic components of brain. The results suggest that the synaptosomal RNA is a membrane-bound fraction with distinctive properties.This research was supported by grants from NIH (NS09407) and the Grant Foundation.     

Changes of synapsin I messenger RNA expression during rat brain development

Synapsin I is a synaptic phosphoprotein that is involved in the short-term regulation of neurotransmitter release. In this report we present the first extensive study of the developmental expression of its corresponding messenger ribonucleic acid (mRNA) by in situ hybridization and northern blot analysis in rat brain. Synapsin I mRNA showed pronounced differences in expression in different brain regions during postnatal development. The early expression of synapsin I mRNA in ontogenetically older regions such as the thalamus, the piriform cortex and the hippocampus coincides with the earlier maturation of these regions, in contrast to its later expression in ontogenetically younger areas such as the cerebellum and the neocortex. An intriguing expression pattern was found in the hippocampus. In all hippocampal subregions synapsin I mRNA expression increased from postnatal day (PND) 1 to 17. After PND 17, however, there was a marked dissociation between persisting high expression levels in CA3 and the dentate gyrus and a strong decline in synapsin I mRNA expression in CA1. The persistence of synapsin I in some adult rat brain regions indicates that it plays a part in synapse formation during plastic adaption in neuronal connectivities.     

Dnm3os,a non‐coding RNA,is required for normal growth and skeletal development in mice

Dnm3os, a gene that is transcribed into a non‐coding RNA (ncRNA), contains three micro RNAs (miRNAs), miR‐199a, miR‐199a*, and miR‐214, whose functions remain unknown in mammals. In this study, we introduced the lacZ gene into the Dnm3os locus to recapitulate its expression pattern and disrupt its function. Dnm3os^+/lacZ heterozygous embryos showed β‐galactosidase activity, which reflected the authentic expression pattern of Dnm3os RNA. Most of the Dnm3os^lacZ/lacZ homozygous pups died within one month of birth. After birth, Dnm3os^lacZ/lacZ mice exhibited several skeletal abnormalities, including craniofacial hypoplasia, defects in dorsal neural arches and spinous processes of the vertebrae, and osteopenia. Importantly, the expression of miR‐199a, miR‐199a*, and miR‐214 was significantly down‐regulated in Dnm3os^lacZ/lacZ embryos, supporting the assumption that Dnm3os serves as a precursor of these three miRNAs. Thus, Dnm3os has emerged as an miRNA‐encoding gene that is indispensable for normal skeletal development and body growth in mammals. Developmental Dynamics 237:3738–3748, 2008. © 2008 Wiley‐Liss, Inc.     

The expression of parathyroid hormone messenger RNA in normal and abnormal parathyroid tissue.

The distribution and expression of preproparathyroid hormone (PTH) mRNA were investigated in parathyroid tissue from 57 parathyroidectomy specimens. PTH mRNA was detected by in situ hybridization using digoxigenin-labelled oligonucleotide probes. Cell morphology was seen to correlate with PTH mRNA expression. Strong expression of PTH mRNA was confined to cells which on haematoxylin and eosin staining had large vesicular nuclei. These included both vacuolated and non-vacuolated cells. Chief cells with small dark nuclei and scanty cytoplasm had little or no expression. In both adenoma and chief cell hyperplasia, the striking difference from normal was the greatly increased proportion of cells expressing PTH mRNA. In adenomas, the rim of uninvolved parathyroid tissue showed PTH mRNA expression similar to that of normal parathyroid. In hyperplasia, there was frequently concordance of staining within individual nodules. The findings establish morphological criteria for activity of parathyroid tissue and support current concepts of the different pathogenesis of hyperplasia and adenoma. The expression of PTH mRNA in oxyphil change and parathyroid carcinoma was also investigated.     

Chronic neonatal exposure of rats to the opioid antagonist naloxone impairs propagation of cortical spreading depression in adulthood

Naloxone is an opioid receptor antagonist with effects on the EEG and behavior in animals and humans and has been used clinically in drug-abuse treatment. The goal of this work in the rat is to determine whether treatment with naloxone during the suckling period would influence the propagation of cortical spreading depression (CSD), both in weaned young and adult animals. From the 7th to the 28th postnatal day, male rat pups were treated daily with a single subcutaneous injection of either 10mg/kg/d naloxone (n=21 rats) or equivalent volume (10ml/kg) of saline (n=16). In both treatment conditions, when the pups were 30-40 days- (young groups; 9 Naloxone- and 10 saline-treated rats), or 90-120-days old (adult groups; 12 Naloxone- and 6 saline-treated rats), a 4h CSD recording session was performed with electrodes at two points at a fixed distance apart on the parietal cortical surface. CSD propagation velocity was calculated based on the time spent for a CSD-wave to pass between the electrodes. In both young- and adult groups, naloxone-treated animals displayed lower CSD velocities (P<0.05) than the corresponding saline injected animals. Our results demonstrate, for the first time, that chronic neonatal exposure of rats to the opioid antagonist naloxone results in an impairing propagation of the CSD that is long lasting, suggesting the existence of one or more opioid-mediated processes influencing CSD.     

Immunohistochemical localization of protein kinase C-alpha in the retina of pigs during postnatal development

The cellular localization and protein expression level of protein kinase C (PKC)-alpha was examined in pig retina at different ages. Western blot analysis detected PKC-alpha in the retinas of 3-day-old piglets and indicated significantly increased expression in 6-month-old young adult and 2-year-old adult pigs. Immunohistochemistry of 3-day-old retinas revealed intense PKC-alpha reactivity in the inner plexiform and inner nuclear cell layers, weak reactivity in the ganglion cell layer, and few positive cells in the outer nuclear cell layer. The cellular localization of PKC-alpha in the adult retina was similar, with staining more intense than that in neonates. PKC-alpha was co-localized in some glial fibrillary acidic protein-positive cells and glutamine synthetase-positive cells in the retina. This study demonstrates that the protein level of retinal PKC-alpha is increased with maturation and suggests that PKC-alpha plays a role in signal transduction pathways for postnatal development in porcine retina.     

长链非编码RNA AK046999在小鼠大脑皮质发育中的表达及功能

目的检测长链非编码RNA AK046999在小鼠大脑皮质发育过程中的表达及作用。方法 1)通过UCSC基因组浏览器获取其基因组座位,利用Coding Potential Calculator工具对其编码能力进行预测;2)原位杂交及免疫荧光技术确定其在大脑皮质发育过程中的表达谱;3)TALEN技术构建AK046999完全敲除小鼠,并且在DNA及RNA水平对其进行敲除鉴定;4)免疫荧光及TUNEL技术对敲除小鼠大脑皮质在发育过程的功能进行检测。结果 1)AK046999可认为是非编码RNA(Coding Potential Score-1);2)AK046999在小鼠大脑皮质发育过程中,前体区相对高表达;3)成功构建了AK046999敲除小鼠;4)与对照相比,AK046999敲除小鼠中表达PAX6、TBR2和NEUROD2的细胞数量无明显改变,并且在这两组小鼠中凋亡细胞的数量无明显改变。结论 AK046999在发育期的小鼠大脑皮质表达,但敲除后不影响小鼠大脑皮质中神经祖细胞的增殖、分化和细胞凋亡过程。     

长链非编码RNA BCYRN1与相关疾病的研究进展

BCYRN1是一种长链非编码RNA,在大脑中高水平表达,并在多种肿瘤类型和其他系统疾病中表达升高。随着对BCYRN1研究的深入,发现BCYRN1与肿瘤、神经系统疾病、呼吸系统疾病以及其他系统疾病密切相关并扮演着重要角色。本文总结了BCYRN1在不同疾病的作用及相关机制的研究进展,为深入了解BCYRN1是如何影响和促进疾病的发生、发展过程提供一点参考或启示。     

阿尔茨海默病小鼠脑组织长链非编码RNA与信使RNA表达谱及调控网络的分析

目的 分析阿尔茨海默病（AD）小鼠脑组织长链非编码RNA（LncRNA）和信使RNA（mRNA）表达谱,构建竞争内源性RNA（ceRNA）调控网络,探讨差异表达LncRNA在AD发病机制中的潜在作用。方法 选取3只10月龄雄性APP/PS1转基因小鼠作为AD组,3只年龄及体质量相匹配的普通C57小鼠作为对照组。使用基因芯片技术检测2组小鼠脑组织LncRNA和mRNA的表达,筛选出差异表达的LncRNA和mRNA。对部分差异表达的LncRNA进行实时定量聚合酶链反应（qRT-PCR）。对差异表达的mRNA进行基因本体论（GO）和京都基因、基因组百科全书（KEGG）通路分析。随机挑选6个差异表达LncRNA构建ceRNA网络,进行AD的靶基因功能预测分析。结果 与对照组相比,AD组小鼠脑组织差异表达1.5倍以上的LncRNA有933个,其中上调222个,下调711个;差异表达1.5倍以上的mRNA有529个,其中上调189个,下调340个。qRT-PCR检测结果显示,AD组与对照组比较,7个差异表达的LncRNA上调或下调趋势与基因芯片结果一致,差异均有统计学意义（P值均<0.05）。GO和KEGG通路分析结果显示,差异表达基因主要参与氨基酸代谢、炎症反应和免疫反应。ceRNA调控网络靶基因的功能富集分析显示,LncRNA在胰岛素抵抗以及糖尿病并发症中的AGE-RAGE信号通路中显著富集。结论 AD小鼠脑组织LncRNA表达谱发生显著变化,由LncRNA Dgkb、Svip等构建的ceRNA调控网络有助于增进对AD发病分子机制的研究,差异表达的LncRNA或通路有可能成为潜在的治疗靶点。     

Ontogenetic development, differentiation, and phenotypic expression of macrophages in fetal rat lungs.

Development, differentiation, and distribution of macrophages in fetal rat lungs were investigated immunohistochemically using anti-rat macrophage monoclonal antibodies. In the lung buds, RM-1+ macrophages were first detected on fetal day 13, and some showed reactivity for TRPM-2. They populated in the peribronchial mesenchyme of the lung buds, proliferated in loco, and showed no peroxidase activity in any intracellular organelles. Their immunophenotypic and ultrastructural features were consistent with those of primitive/fetal macrophages. By fetal day 16, some of them expressed ED1, but ED1+ cells were a minor subpopulation throughout the fetal period. On fetal day 18, ED2+ macrophages developed; some also were positive for RM-1, but the others were negative. Both the RM-1+ and ED2+ macrophages were major macrophage subpopulations and expressed Ki-M2R and/or TRPM-3; ED2+ and/or Ki-M2R+ cells are regarded as pulmonary interstitial resident macrophages. In organ culture, a similar expression of differentiation antigens by macrophages was confirmed. None of these macrophages cytochemically showed any peroxidase activity in vivo or in vitro. In the fetal stage, both RM-1+ and ED2+ macrophage subpopulations showed proliferative potential, suggesting their ability to proliferate and survive in vivo.     

长链非编码RNA在卵巢癌中的研究进展

长链非编码RNA (lncRNA)是指长度超过200个核苷酸、具有调控基因表达作用的非编码RNA,近年来,因其具有复杂的生物学功能而引起了研究者的广泛关注.目前研究证实,lncRNA与多种肿瘤的发生发展有着密切的关系,可能参与促进或抑制肿瘤的生长和与肿瘤的转移有关.在卵巢癌中,某些lncRNA也被证实可能参与其致病过程.     

RNA helicase Mov10 is essential for gastrulation and central nervous system development

Background: Mov10 is an RNA helicase that modulates access of Argonaute 2 to microRNA recognition elements in mRNAs. We examined the role of Mov10 in Xenopus laevis development and show a critical role for Mov10 in gastrulation and in the development of the central nervous system (CNS). Results: Knockdown of maternal Mov10 in Xenopus embryos using a translation blocking morpholino led to defects in gastrulation and the development of notochord and paraxial mesoderm, and a failure to neurulate. RNA sequencing of the Mov10 knockdown embryos showed significant upregulation of many mRNAs when compared with controls at stage 10.5 (including those related to the cytoskeleton, adhesion, and extracellular matrix, which are involved in those morphogenetic processes). Additionally, the degradation of the miR‐427 target mRNA, cyclin A1, was delayed in the Mov10 knockdowns. These defects suggest that Mov10's role in miRNA‐mediated regulation of the maternal to zygotic transition could lead to pleiotropic effects that cause the gastrulation defects. Additionally, the knockdown of zygotic Mov10 showed that it was necessary for normal head, eye, and brain development in Xenopus consistent with a recent study in the mouse. Conclusions: Mov10 is essential for gastrulation and normal CNS development. Developmental Dynamics 247:660–671, 2018. © 2017 Wiley Periodicals, Inc.