Effect of recombination signal binding protein for immunoglobulin Kappa J region on the proliferation and differentiation of CD133-positive ependymal cells / 解剖学报

Objective To explore the effect of recombination signal binding protein for immunoglobulin Kappa J region (RBP-Jκ) on the proliferation and differentiation of CD133￣positive ependymal cells and its possible mechanism. Methods RBP-Jκ in CD133-positive ependymal cells of lateral ventricle was interfered with siRNA in the fetuses of embryos which were isolated from 12-day pregnant Institute of Cancer Research(ICR) mouse (3 mice) and knocked out in CD133-CreER

Ependymoma with Intraorbital Extracerebral Recurrence: Case Report

Ependymomas are rare neuroepithelial tumors that originate from a type of glial cell called ependymal cell. In general, they correspond to 1.2 to 7.8% of all intracranial neoplasms, and to2 to 6%of all gliomas. Although it corresponds only to2 to 3%of all primary brain tumors, ependymoma is the fourthmost common cerebral neoplasmin children, especially in children younger than 3 years of age.1,2 In patients younger than 20 years of age, the majority (90%) of ependymomas are infratentorial,more precisely from the IV ventricle. In spite of this, in adults, medullary ependymomas are more frequent (60%). In this context, supratentorial and extraventricular ependymomas, as in the case reported in the present article, are infrequent in both adults and children.1,2 Both sexes are equally affected.3 Recurrence of intracranial ependymomas occurs in almost 50% of the cases, and the followup outcome is not favorable.4 In another perspective, the recurrence of extracerebral ependymomas is extremely rare, and even more unusual in the intraorbital site, as it occurred in the case in question.

Expeiment study on the proliferation and plasticity of ependymal cells in situ in the injuried spinal cord of adult rats / 中国矫形外科杂志

[Objective]To observe the proliferation and plasticity of neural stem cells in sim in adult rats after spinal cord injury.[Method]Spinal cord injury models were made in 60 wistar rats and the dynamic expression of bromodeoxyuridine(BrDU) and polysialylated ependymal cells adhesion molecule(PSA-NCAM) were determined by immuno-histochemisty.[Result]Compared with the controls,the number of Brdupositive cells in the injured spinal cord increased strikingly on the 1 st day (P

The Effect of Ependymal Cell Transplantation on Nerve Regeneration after Spinal Cord Injury in Rats / 대한해부학회지

Nerve regeneration in the central nervous system has been studied by grafting various tissues and cells. Choroid plexus epithelial cells represent a continuation of ventricular ependymal cells and have the same origin as regarded as modified ependymal cells. To study the use of choroid plexus ependymal cell grafting for nerve regeneration in the spinal cord, the choroid plexus was excised from the lateral and fourth ventricles of adult Sprague-Dawley rats, minced into small fragments, and grafted at the T9 level in adult rat spinal cord transected or contused. In this study, transplants of choroid plexus ependymal cells were successfully used to promote functional and structural recovery after spinal cord transection and contusion. The area of damaged spinal cord was diminished after choroid plexus ependymal cells transplantation. Nearly normal anterior horn cells were observed immediately distal to the transected region. Tyrosine hydroxylase immunoreactive descending fibers were observed in the distal region beyond transected area. These findings indicate that choroid plexus ependymal cells have the ability to facilitate axonal growth, suggesting that they may be a promising candidate as graft for the promotion of nerve regeneration in the spinal cord.

Developmental Changes of Glial Fibrillary Acidic Protein (GFAP) and Proliferating Cell Nuclear Antigen (PCNA) Immunoreactivity of the Ependyma lining the Central Canal and Ventriculus Terminalis in the Human Fetus / 대한해부학회지

The distinguishing morphological features of the ependyma lining ventriculus terminalis in human fetus have suggested that its differentiation would be somewhat delayed or arrested as compared with the ependyma lining central canal. To demonstrate this hypothesis, GFAP was used as a marker to compare the developmental state of the ependyma lining ventriculus terminalis and central canal along fetal age (18 -to 24 -week -old fetuses were investigat-ed). PCNA was also used as a marker to identify whether proliferation potentiality of the ependyma lining ventriculus terminalis lasted longer than that of the ependyma lining central canal as a result of differentiation delay. GFAP -positive ependymal cells were restricted to dorsal plate at central canal but at ventriculus terminalis, many positive cells were identified in all regions compared with the ependyma lining central canal. The number of PCNA -positive ependymal cells lining central canal decreased sharply about the time of 20th week, but at ventriculus terminalis, many ependymal cells continued to express PCNA after 20th week. As a result, we could conclude that differentiation of the ependyma lining ventriculus terminalis is delayed as compared with the ependyma lining central canal. In accordance with its developmental delay, it lasts longer proliferation potentiality than the ependyma lining central canal.

Morphological Study of the Ventriculus Terminalis in the Human Fetal Spinal Cord / 대한해부학회지

The ventriculus terminalis, also known as the 'fifth ventricle', is a dilated cavity in the conus medullaris. It is formed by degenerative process in the course of neural tube development, but the definite function is unclear. And the reports, which have studied the morphological variation according to fetal age, are insufficient. So, in this report, we observed the morphological variation of the ventriculus terminalis and measured the areal ratio of the ventriculus terminalis to the parenchyma of conus medullaris by fetal age. We also studied the fine structure of the conus medullaris and ependyma by electron microscope. The ventriculus terminalis began at the level at which the ependymal cells proliferated and the central canal moved to the dorsal region. Periependymal islet was observed at this level. At the lower level, it immediately extended both lateral sides and finally switched over to the filum terminale. The area ratio of the ventriculus terminalis to the parenchyma of the conus medullaris increased from above downward. Especially, It increased steeply between the Leaf-shaped region and the transitional zone, where the ventriculus terminalis began. But the increasing pattern was too irregular to generalize its pattern by fetal age. The ependyma lining the ventriculus terminalis was composed of pseudostratified ciliated columnar epithelium layer about 5~7 cells thick. It had conspicuous intercellular junctional complexes close to the lumen into which microvilli and cilia projected. At the junction where the ependyma meets the parenchyma of the conus medullaris, we could observe many myelin-like structures made by basolateral membrane of the ependymal cell. In the conus medullaris, we could observe many obscure cell types because they were in the course of differentiation. On the other hand, we could also observe the fully differentiated nerve cells, astrocytes and oligodendrocytes which seemed to play its own role. A lot of developing myelin sheaths were observed and the majority was the degenerative one. Some ependymal cells showed the apoptotic characteristics and many cell debris were observed in the lumen. As a result, the ventriculus terminalis was formed by the combination of cell differentiation and degeneration, and its development was independent of the spinal cord.

EXPRESSION OF N-METHYL-D-ASPARTATE RECEPTOR SUBUNIT-1 IN EPENDYMAL CELLS OF THE THIRD VENTRICLE OF RAT / 解剖学报

Objective To explore the expression of N-methyl-D-aspartate receptor subunit-1 (NMDAR1) in the ependymal cells of the third ventricle of rat. Methods The immunohistochemistry technique was used. Results (1)NMDAR1-immunoreaction (NMDAR1-IR) was strongly expressed in the ependymal cells of the third ventricle; (2)There was no significant sex difference in morphology and distribution of the NMDAR1-IR ependymal cells between male and female. Conclusion The present investigation provided the morphological evidence supporting that glutamate of CSF might regulate ependymal cells via NMDAR.

Morphologic changes of intermediate filaments of ependymal cells in experimentally induced hydrocephalic rats / 대한해부학회지

Ependymal cells line the surface of cerebral ventricles. They do not regenerate after they are fully matured and have a limited response to injury. In hydrocephalus, the expansile force of the ventricular wall is applied to ependymal cells and causes cell deformity to some degree. As it is known that the intermediate filaments of a cell act as a framework that resists changes in cellular shape, there may be some detectable changes of intermediate filaments of ependymal cells in hydrocephalus. In developing ependymal cells, it is also unclear if there are any changes to intermediate filaments in hydrocephalus. Developing ependymal cells are known to lose their immunoreactivity to glial fibrillary acidic protein (GFAP), a kind of intermediate filaments which exist in some neuroglial cells. We experimentally induced congenital and postnatal hydrocephalus and investigated the changes of immunore-activity against GFAP as well as the ultrastuctures of rat ependymal cells in both types of hydrocephalus. To induce congenital hydrocephalus, 40 mg/kg of ethylenethiourea (ETU) was orally administered to pregnant rats on the 15th day after conception. Tissues taken from fetuses on the 17th day, from newborn rats immediately after birth, and from rats of 1 week and 2 weeks after birth were obtained and processed for immunohistochemistry for GFAP and electron microscopy. Postnatal hydrocephalus was induced by injecting kaolin suspension into the subarachnoid space of 15-day-old rats. Ependymal tissues were obtained and processed for immunohistochemistry and electron microscopy after 1 and 2 weeks following injection. The results were as follows; 1. Congenital hydrocephalus was induced more consistently and extensively than postnatal hydrocephalus. 2. In congenital hydrocephalus, GFAP-reactive ependymal cells were found in lateral ventricles of 1-week and 2-week-old rats, while in control and postnatal hydrocephalic groups, GFAP-reactive ependymal cells were not found. GFAP-reactive cells tended to be found in clusters. 3. Electron microscopy showed ependymal cells in congenital hydrocephalus had a less marked flattening figure, scarce apical cilia, often widened regions in the intercellular gap, spaces in subependymal tissue, and different figures in mitochondria. Above all, intermediate filaments, including GFAP, increased and were irregularly arranged in ependymal cell cytoplasm in congenital hydrocephalus. Therefore, in congenitally-induced hydrocephalus, the ependymal cells appeared to have a greater responsiveness to expansile force and remained in a more premature state than postnatally-induced hydrocephalus.

Ultrastructural Changes of Ventricular Wall in Hydrocephalic Rats

Morphological changes in the ependymal lining of the hydrocephalic brain included stretching and tearing of the ependyma, thickening and gliosis of the subependymal layer, progressive loss of cilia and microvilli from the ependymal surface, and widening of the extracellular space. In the CT scan of the brain, periventricular low density was one of the common findings in hydrocephalus. The present experiment was performed to investigate not only the ultrastructural changes of the ventricular walls in hydrocephalus but also the morphological basis of periventricular lucency detected in the brain CT scan of the hydrocephalic patients. Hydrocephalus was induced in rats by intracisternal injection of thick kaolin suspension after surgical exposure of atlanto-occipital membrane. Lateral wall of the lateral ventricle was examined with transmission electron microscope in 3 different groups(6 rats at 1 week after the hydrocephalus, 8 at 2 weeks, and 4 at 8 weeks). The results were as follows: 1) Ultrastructural changes of the ependymal lining in hydrocephalic rat were flattening of ependymal cell and its nucleus, loss of cilia and microvilli from the ependymal surface, widening of the junctional complex, vacuoles and enlargement of cisternal space of rough endoplasmic reticulum in cytoplasm, and thicking and gliosis of subependymal layer. 2) These changes became more severe with longer duration of hydrocephalus. 3) Widening of junctional complex was considered to be the morphological basis for migration of ventricular cerebrospinal fluid into the periventricular white matter with resultant periventricular low density in the CT scan of the brain.

Ultrastructural Observation on the Wall of Fourth Ventricular Foramina Following Intraventricular Blood Infusion in the Cat: A Transmission and Scanning Electron Microscopic Study

The ultrastructural changes of the wall of the fourth ventricular foramina following intraventricular autogenous blood infusion present four meaningful findings for the patho-genesis of secondary hydrocephalus. Using the transmission and scanning electron microscopy (TEM and SEM), it has found that minimal to marked separation of the intercellular cleft coincided with the intra-and intercellular vacuolation and swelling of the glial fibers in the subependymal glial sheath by the 7th day of blood infusion. A f1attening of the contours of the ependymal cells and their nuclei was noted under the TEM and a seperation of ependymal cells was pronounced under the SEM during the period between the 28th and 42nd day. Ultrastructural changes of the ependymal cells correlated with the time factor and not with the blood volume infused. The supraependymal cells (SEC) seen on the ventricular surface were indicative of neuron-like structure rather than macrophages.

ULTRASTRUCTURAL CHANGES OF CEREBRAL TISSUE IN THE LATERAL RECESS OF THE FOURTH VENTRICLE IN BALB/c MICE AFTER SINGLE ORAL ADMINISTRATION OF STERIGMATOCYSTIN / 解剖学报

Objective To investigate the effects of sterigmatocystin(ST) on the ependymal cells,neurons and endothelial cells of blood vessel of the lateral recess of the fourth ventricle in BALB/c mice in vivo after single oral administration. Methods BALB/c mice were treated intragastrically by gavage with ST 3000??m/kg.The mice were killed 1 hour,2 hours,4 hours,8 hours,16 hours after oral administration respectively for observing ependymal cells,neurons and endothelial cells of blood vessel of the lateral recess with transmission electron microscopy(TEM).Results After oral administration of ST pinocytosis vesicles began to increase in endothelial cells of blood vessel in 1 hour,apocrine of ependymal cells began to increase and myelin sheath degeneration appeared in 2 hours,extensive myelin sheath degeneration and mitochondrion degeneration and incisure and vacuoles in nucleus of neuron were found in 4 and 8 hours.Lipofuscin was found in cytoplasm of neuron 16 hour.Conclusion Oral ST exposure in mice could cause myelin sheath degeneration and damaged changes of neurons.