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The work is based on the results of histological and immunohistochemical studies performed on the sectional material of 104 human corpses (59 men and 45 women) of young and old age. A comparative analysis of the morphological characteristics of the corpus callosum tissues using hematoxylin and eosin staining, the Nissl method (by Snesarev), by Van Gieson, by Spielmeyer, by Foot. An immunohistochemical study of the samples used a panel of antibodies to glial fibrillar acid protein (GFAP), the S-100 protein. It was found that by senile age, the tissue of the corpus callosum is characterized by the accumulation of glial macrophages. With age, there is a proliferation of GFAP-immunopositive astroglia. There is no dynamics of S-100 protein expression with age. Thus, the revealed regularity of age-related variability of the cytoarchitectonics of the corpus callosum is of interest in diagnostic and therapeutic work, and its morphological picture in old age can serve as an equivalent of the anatomical norm.

In this science work there were conducted such researches as organometric, histological, immunomorphologic and morphometric of cerebellar cortex of 219 corpses of people (108 man and 111 woman) of young and old age. A comparative analysis of the parameters of bulb-shaped neurons in these ages revealed decrease of their height and width. It is found that distance between interval nerve cell bodies of ganglionic layer increases with age that obviously associated with progressing disorganization and death of bulb-shaped neurons. It is marked an increment in the number of immunopositive for glial fibrillary acidic protein, protide S-100 and vimentin astrocytes in granular layer and molecular layer of cerebellar cortex, and decline in the number of immunopositive for neuron-specific enolase and immunonegative for protide S-100 and vimentin bulb-shaped neurons that can be regarded as manifestation of neurodegeneration. Using immunohistochemical methods in research allows approaching more differentially to the issues of morphological assessment cerebellar cortex of elderly people and gives an opportunity to receive more objective and full information of postnatal morphogenesis.

Glial fibrillary acidic protein (GFAP) refers to the type III intermediate filament proteins and is the essential component of the cytoskeleton in astrocytes of all vertebrates. This review presents current data on the molecular organization of GFAP in a comparative aspect. The results of most relevant studies using immunocytochemical labeling of the protein are summarized. The data on the changes in expression of GFAP in Alexander disease caused by the primary pathology of astrocytes are presented.

Objective: To examine the specific features of cell differentiation and migration of neuroepithelial cells of the paraventricular region (PVR) in human fetuses with in utero encephalitis., Materials and Methods: A morphometric technique was used to investigate the expression of vascular endothelial growth factor, tumor necrosis factor-alpha, and transforming growth factor-beta in the structures of the PVR of the thalamus in 47 fetuses with signs of in utero encephalitis and in 10 healthy fetuses at 26-27 weeks' gestation., Results: In utero encephalitis was characterized by productive and productive-and-necrotic inflammation and in most cases it was a manifestation of generalized in utero infection. In in utero encephalitis, diminished PVR cellularity, a larger number of neurons and glial cells in the thalamic region, and that of glial fibrillary acidic protein-expressing cells, and enhanced cellular proliferative activity in the PVR implied the accelerated maturation of its cells. The decrease in the number of vessels in the PVR was caused by the lower cellular expression of vascular endothelial growth factor and transforming growth factor., Conclusion: In in utero encephalitis, there are significant changes in the processes of cell differentiation and migration in the fetal PVR, which was associated with a number of cytokines regulating an intercellular interaction.

The ability of mesenchymal stem cells (MSCs) to differentiate into neuronal lineage determines the potential of these cells as a substrate for a cell replacement therapy. In this paper we compare the neurogenic potential of MSCs isolated from bone marrow (BMSC), subcutaneous adipose tissue (AD MSC) and menstrual blood (eMSC). It was found that the native eMCSs, BMSCs and AD MSCs express neuronal marker β-III-tubulin with a frequency of 90, 50 and 14%, respectively. We also showned that eMSCs have a high endogenous level of brain-derived neurotrophic factor (BDNF), whereas the BMSCs and the AD MSCs are characterized by low basal BDNF levels. As induction of neuronal differentiation in the studied MSCs using differentiation medium containing B27 and N2 supplements, 5-azacytidine, retinoic acid, IBMX and dbcAMF caused changes in the cells morphology, the increased expression of β-III-tubulin, and the appearance of neuronal markers GFAP, NF-H, NeuN and MAP2. BDNF secretion during differentiation was significantly enhanced in the BMSCs and decreased in the eMSCs cultures. However, no correlation between the basal and induced levels of the neuronal markers expression and BDNF secretion in the studied MSCs has been established.

This article reports an original observation of a few cases of brain injury in subjects presenting with elevated blood pressure. The standard histological staining techniques and immunohistological method were used to detect GFAP in astrocytes. The morphological features of this type of brain injury in the elderly subjects are described, the possibility of using them for the analysis of the damage is considered.

Complex application of lisinopril (inhibitor of angiotensin-converting enzyme) and lovastatin (inhibitor of HMG-CoA reductase) inhibits pancreatic fibrosis in the rats, having alcoholic chronic pancreatitis after distal pancreatic resection (DPR). Lisinopril and lovastatin were injected to the rats after DPR in dose 10 mg/kg during 3 weeks. Immunohistochemical markets, such as alpha-smooth-muscle actin (alpha-SMA), desmin, glial fibrillary acidic protein (GFAP), vimentin, and expression of matrix metalloproteinase-1 (MMP-1) as well as inhibitor of matrix metalloproteinase-2 (TIMP-2) were detected for estimation of therapeutic impact on activity and quantity of stellate pancreatic cells. Under the influence of lisinopril and lovastatin there were observed lowering in the stellate pancreatic cells activity and in expression of SMA, desmin, GFAP, vimentin and TIMP-2, the MMP-1 and TIMP-2 ratio have had increased significantly and severity of fibrotic pancreatic affection had reduced trustworthy in comparison w such, occurring in a control group.

The aim of this study was to detect structural, spatial and quantitative changes of cellular elements of midbrain paranigral nucleus (PNN) and telencephalic anterior cingulate area (ACA) under different conditions of circulatory hypoxia. PNN anteriormedial part and ACA layers V-VI were examined in adult rats 7 days (n=4) after an occlusion of both common carotid arteries as well as in intact (1st control, n=4) and sham-operated animals (2nd control, n=4). In histological the sections, stained with Nissl cresyl violet, and using the methods of glial fibrillary acidic protein and an Ibal-protein detection, the proportions of unmodified, hypochromic, pyknomorphic neurons and ghost cells were determined as well as the numbers of astrocytes, oligodendrocytes, microgliocytes and endotheliocytes. Cell body area of neurons and gliocytes, and the distance between cell bodies and capillaries were measured, a gliocyte-neuronal index was calculated. It was found that brain cellular elements that survive different conditions of a circulatory hypoxia underwent a range of pathological changes. Neurons were in process of nuclear pyknosis, lysis and transformation into the ghost cells. The cells within the hypoxia nuclear zone were prone to death or pyknosis. The neurons located outside the area of hypoxia which were affected only by a humoral impact of reactions of the glutamate-calcium cascade, frequently underwent acute swelling. Microgliocyte reaction in the form of poorly expressed increase in their number and structural signs of activation was an early diffuse manifestation of a prosencephalic focal hypoxia. Endotheliocyte proliferation 7 days after of ischemic challenge was not associated with a chain of cascade reactions and was observed only in the hypoxia focus. Concentration of viable neurons and astrocytes near blood capillaries, as well as an increase in the number of satellite form gliocytes is an adaptation mechanism and a condition for the survival of cells during various types of brain exposure to ischemia.

Apoptosis and differentiation in presumptive neural retina (PNR) and presumptive retinal pigmented epithelium (PRPE) wert investigated during early retina development of toad, Bufo raddei Strauch. TUNEL staining was used to evaluate apoptotic cells and the immunohistochemistry was used to assess the expression levels ofglial fibrillary acidic protein (GFAP), RT97 and tyrosinase (Tyr) during early eye development respectively. The density of apoptotic cells and protein expression were quantitated with Image-Pro Plus 6.0. Apoptosis was found in both PNR and PRPE and the density of apoptotic profiles in PRPE was higher than that in PNR (most P<0.01) at the same stage during early eye development. The expression levels of GFAP and RT97 changed from low to high in PNR, but from high to low in PRPE, whereas the expression level of Tyr, was contrary to those of GFAP and RT97 in both PNR and PRPE. The point of intersection of these, increase and decrease respectively was found at 5-6 h after formation of optic vesicle (FOV). PRPE becomes thinner than PNR, one of the reasons might be due to higher density of apoptosis in PRPE than that in PNR during early eye development. Molecular differentiation, however, occurred after the contact of the optic vesicle outer wall with the overlying ectoderm which promotes the expression of specific molecules and inhibits the expression of non-specific molecules in PNR and PRPE respectively.

Importance of study of astrocytes for fundamental biology and medicine is due their key role in formation of the brain barrier system. On taking into consideration the controversial data on structure of the mammalian neocortex superficial layers, of great actuality are the comparative studies of the structural and cytochemical organization of astrocytes in human and in the laboratory animals used in the experimental studies connected with modeling of brain diseases and traumas. The goal of the present work was to study structural organization of astrocytes in the human and rat neocortical layer I. The work was on the autopsy and experimental material from Wistar rats. Astrocytes were revealed immunocytochemically by using antibodies to GFAP, vimentin and nestin. The preparations were examined with aid of light and confocal laser microscopy. No significant difference in the sizes of perinuclear areas were established between the rat and human astrocytes. In the majority of cortex regions, the specter of proteins forming intermediate filaments in these cells was identical. However, there were essential differences revealed in organization of the superficial glial bordering lamina (SGBL). The human SGBL is formed by interlacing of thin processes in the layer I processes, whereas the rat SGBL is represented by specialized astrocytes spread along the cortical surface and connected with the wide-blade processes. The human layer I astrocytes have translaminar processes passing via several cortical layers, whereas in rats such processes are located within the limits of one layer. The revealed differences in the astrocyte structural organization should be taken into account when interpreting results of experimental studies carried out on rats and extrapolating these results to human.

The purpose of this study was to investigate the expression of intermediate filament proteins (vimentin and glial fibrillary acidic protein--GFAP) in the cells of embryonic rat neocortex at different time points after its allotransplantation into injured sciatic nerve of adult animals. Using immunohistochemical methods, the differentiation of GFAP-positive astrocytes from vimentin-positive radial glial cells was observed in embryonic rat neocortex, grafted into sciatic nerve. It was shown that the differentiation of the embryonic neocortical astrocytes in the transplants took place a few days earlier than in the rat neocortex during normal ontogenesis. Reactive gliosis was demonstrated in the long-term transplants, as indicated by a large number of intensely stained GFAP-positive cells and vimentin-containing astrocytes. These findings suggest that ectopic neurotarnsplants could serve as a model for fundamental studies of the mechanisms of reactive gliosis development.

Subventricular proliferative zone is the brain area most intriguing and least understood in terms of cellular and spatial organization. The objective of this study was to focus on the structural and cytochemical organization of astrocytes of the subventricular zone of the rat brain. Astrocytes were detected immunocytochemically. The preparations were analyzed using conventional light microscopy and confocal laser microscopy. The study performed showed that the major cellular population of the subventricular zone was represented by a special kind of atypical fibrous astrocytes with the intermediate filaments containing only glial fibrillary acidic protein (GFAP). The processes of these cells formed a complex double-layer network beneath the ependyma. The described structural pattern of the glial skeleton of the subventricular zone seems to be determined by specific functions of the area and its location in the zone of CSF-brain barrier.

The morphology of neural and glial cells in different cerebral areas and in various experimental models was quantitatively studied by methods of computer morphometry combined with video image analysis systems. The following parameters were obtained: density of neurons and glial cells per 1 mm(2), number of satellite perineuronal glial cells, aspect ratio for neural and glial cells, the area occupied by neuroglial projections, etc. The tested computer morphometry methods can be efficient in quantitative assessment of pathological and regenerative processes in the nervous tissue.

Adult rat and newt retinas were studied during long organotypic 3D cultivation. A high proliferation level was discovered in the region of growth by applying DNA synthesis markers and in vitro mitosis registration in newt retina. Aggregates were formed in the retina spheroid cavity because dedifferentiated cells migrated into this region. Small cell populations in nuclear layers also had dividing and migration capacity. Rosette formation has been shown in newt retina. It is a characteristic of fetal retinal development under pathological conditions. The antiG FAP antibody dye demonstrated an increase in the parent M@uller cell population and generation of a small cell pool with short GFAP-extensions de novo. Recoverin expression studies detected its translocation from photoreceptor extensions to the cell bodies. Moreover, protein was presented in some cells inside the spheroid. It has been shown for the first time that cell proliferation occurred in the developing adult rat retinal spheroid in vitro; BrdU-positive cells and multiple mitoses were revealed in this zone. However, the source of proliferation was not in the peripheral retina, and stable macrophages and glial cells located among neurons of the inner nuclear layer had the ability to divide. The antiGFAP antibody showed an increase in GFAP fibers in the rat retina as well as in the newt retina. Recoverin translocated into photoreceptor perikaryons and the outer plexiform layer in cultivated rat retina. Interestingly, some cells with probably de novo expression of recoverin were discovered in rat and newt retinas.

The authors report a rare a case of gliosarcoma metastases in a 28-year-old male patient. The cauda equina roots were involved after brain tumor 16 months ago, which, on microscopic study, had a biphasic pattern and heterogeneous staining in the reaction with antibody to GFAP and vimentin; the tumor cells did not express EMA, EA, and desmin. Gliosarcoma was diagnosed, by taking into account morphological and immunohistochemical data. Tumor tissue of the cauda equine roots had the same immunophenotype as the brain tumor with a predominance of glial component, which permitted the source of metastases to be ascertained.

The population of neurosphere cells was studied by staining for the radial glial marker BLBP protein. An immunohistochemical study of cultures showed that neurosphere cells proliferate and retain the ability for pluripotent differentiation over 9 passages. BLBP-immunoreactive cells were present in neurospheres at all passages. However, they did not belong to the population of proliferating multipotent precursors or GFAP-positive cells. BLPB expression was detected in S-100b-positive cells of astrocyte differentiation. Our results suggest that BLBP-immunopositive cells of the radial glia in vitro loss the state of multipotent precursors and differentiate into the astroglia. Otherwise, some heterogeneous cells of the radial glia include a previously unknown linear population that differentiates into S-100b-positive astrocytes.

Motor activity of rats has been studied after complete experimental section of spinal cord at the lower thoracic level. A treadbun training performed one day after the operation has been shown to lead to the appearance of movement of hindlimbs and to restoration of function of support of the body weight. In our opinion, the key moment in initiation of locomotor movements is stimulation of foot. Morphoimmunohistochemical study (detection of nuclear protein of proliferation cells, synaptophysin, and glial fibrillary acid protein) of the lumbar enlargement has allowed revealing reorganization of motoneurons, interneurons, and afferent chain in the distal part of the sectioned spinal cord. In trained animals there are observed the normal structure of motoneurons and the appearance of aggregates of synaptophysin-immunoreactive structures lost after the operation.

Immunohistochemical (tests for insulin, glucagons, periferin, SNAP-25, GFAP, NGF-R, RMR-22, MBP) and morphological studies were performed to examine the pancreatic nervous apparatus of human adults and fetuses in late phases of development. A role of the morphogenetic activity of the pancreatic nervous apparatus was investigated in type 1 diabetes mellitus (DM-1). The neurons and gliocytes located in the pancreas are suggested to have a morphogenetic activity and form a glial capsule throughout their life. The insular endocrine cells are shown to synthesize the proteins (SNAP-25, GFAP) characteristic of nerve cells and their synaptic terminals. A neurobiological model of DM-1 'development has been stated. The onset of the disease is characterized by the development of autoimmune processes directed to the nervous system. In nerve tissue protein autoimmunization, the fine insular neuroglial membrane is rapidly disrupted. This leads to the transfer of autoimmune aggression to the insulin-producing cells of the islets of Langerhans, which carry specific nerve tissue proteins onto their surface. Recovery of the islets becomes impossible without forming a protective neuroglial membrane, which makes the development of DM-1 irreversible.

The data on the presence of the kidney cells can contain neuroglial markers (nestin, vimentin, glial fibrillar acidic protein--GFAP) appeared unexpected and require a detailed investigation. Therefore, the purpose of the current study was to demonstrate the structures containing these proteins in the rat kidney by means of immunocytochemistry. Immunocytochemical staining was performed using the antimouse monoclonal and antirabbit polyclonal antibodies. It was demonstrated that the renal corpuscle contained both nestin- and vimentin-immunopositive cells (podocytes). Vimentin was also detected in the cells of parietal epithelium of the glomerular capsule, single cells of proximal and distal tubular epithelium, medullar tubular structures, and in the stromal cells. No GFAP-positive cells were detected in the kidney. Thus, the combination of nestin and vimentin was found to be typical for adult rat kidney podocytes. This suggests probable similarity of cytophysiological properties of podocytes and activated CNS astrocytes.

Pronounced clinical and morphological changes were found in the neurons and microcirculatory bed (MCB) vessels at the level of the medulla oblongata in experimental West Nile encephalitis (WNE). At the same time, the magnitude of changes in MCB vessels and nerve cells in the cores of the medulla oblongata correlated with the state of the surrounding astrocytic glia. It is suggested that the intensive astroglial reaction revealed during this experimental WNE reproduction promotes the prevention of neuronal lesion.

PEGylated (stealth) immunoliposomes covalently linked to antibodies against human gliofibrillary acidic protein (GFAP) were prepared by coupling the thiolated monoclonal anti-GFAP antibodies, D4, with a maleimide derivative of the phosphatidyl ethanolamine of the liposomal membrane. Depending on the initial protein-to-lipid ratios, the immunoliposomes prepared (with a diameter of about 70 nm) were coupled with 60 to 240 molecules of the antibodies. In vitro experiments with cultures of the embryonic rat brain astrocytes demonstrated a specific binding of these immunoliposomes, which could be inhibited by the preincubation of the cells with free non-coupled D4 but not with non-specific antibodies. Administered intravenously into rats, the immunoliposomes exhibited a kinetic behaviour typical for the PEGylated liposomes: after 24 h, approximately 20% of the doses injected were still present in the blood; the elimination rate constants were 0.05-0.09 h(-1), the elimination half-lives were 8-15 h. With such a systemic longevity, as well as with such a specificity, these immunoliposomes, non-penetrating through intact blood-brain barrier (BBB), should be useful in delivering pharmacological agents to glial brain tumours (which continue to express GFAP) or to other pathological loci in the brain with a partially disintegrated BBB.

Time-course of astrocyte appearance in the neocortex of F1 (CBA/C57B1) mice after prenatal serotonin depletion was studied. To suppress serotonin synthesis, para-chlorophenylalanine was administered to females once at the early postimplantation stage of gestation. To visualize differentiating astrocytes, the immunohistochemical method for demonstration of astrocyte intermediate filament protein--glial fibrillary acidic protein (GFAP) was used, which allowed not only to label the cells, but also to evaluate the starting point, extent and time-course of their differentiation. The results obtained have shown that in all the neocortical areas studied (area cingularis, area occipitalis, area parietalis, area insularis, area praepiriformis, area piriformis, area entorhinalis and area subiculum), normally, GFAP-positive cells appeared in the layer I at postnatal week 1. In the course of development, the process of astrocyte differentiation was shown to become progressively more intensive. At the same time, the process of barrier structures formation took place. During the first days of postnatal development astrocytes and their processes were shown to appear close to the blood vessels and lateral ventricle walls. In the neocortex of animals that developed during the serotonin depletion, GFAP-positive cells were formed in decreased numbers, in particular, in the white matter, at all the stages of postnatal development studied.

Glial fibrillary acidic protein (GFAP) is a brain astrocyte-expressed protein that is recognized as one of the main immunohistochemical markers of these cells. The aim of the present study was to investigate the structure of GFAP-positive astrocytes of human neocortex. Main types of GFAP-immunoreactive astrocytes in the human neocortex were characterized using immunohistochemistry and confocal laser microscopy. These are astrocytes of the layer I forming the surface border glial membrane, translaminar astrocytes of the layer I with very long processes penetrating several cortical layers, astrocytes of middle layers of the neocortex with a general organization of protoplasmic-type astrocytes which are involved in formation of perivascular border membrane, and typical fibrous astrocytes of the white matter. The data obtained will contribute to unification of evaluation of histopathologic processes observed in various kinds of gliosis in the CNS.

The aim of this investigation was to study the distribution and structural organization of rat hippocampal astrocytes containing immunoreactive glial fibrillary acidic protein (GFAP) after ischemic damage of the brain in the animals treated with intraventricular infusion of creatine as a neuroprotective drug, and in those which received no treatment. Using the methods of light microscopy and immunocytochemistry, the brain of 26 mature Sprague-Dawley (Koltushi) rats was studied. Some animals were narcotized and subjected to general brain ischemia (lasting for 12 min) followed by a reperfusion (for 7 days). Creatine was infused intraventricularly to 11 animals using an automatic Alzet osmotic minipump. It was found that GFAP-immunoreactive hippocampal astrocytes were concentrated within two major areas (stratum lacunosum-moleculare CA1 and fascia dentata stratum polymorphae). As a result of neuroprotective effect of creatine, moderate ischemic damage of the hippocampus was not followed by the changes in the zones of activated astrocyte localization. Redistribution of GFAP-positive astrocytes in postischemic period was caused by the loss of pyramidal neurons in cytoarchitectonic field CA1. Complete loss of pyramidal neurons in this hippocampal area resulted in a qualitatively new level of astrocyte activation--their proliferation.

Nestin is a protein that belongs to a family of intermediate filament proteins which are typical for undifferentiated neural stem and progenitor cells. In this work nestin expression was studied in the hippocampus obtained from patients with epilepsy. Immunohistochemical investigation demonstrated five types of nestin-positive cells, differing in morphological and immunological phenotype. These included cell with a radial glia phenotype, bipolar cells, small dendritic cells, subependymal and astrocyte-like cells. Two types of these cells: radial glia of dentate gyrus and bipolar NG2+ cells can be considered as neural progenitor cells possessing different degrees of commitment.

The study was carried out with the aim of determination of morphological and cytochemical properties of human glioblastoma T98G cells in monolayer culture. Using light microscopic and immunocytochemical techniques, the glioblastoma cell line studied was shown to have low susceptibility to the effects of environmental factors and changes in culture conditions as well as high proliferative activity. All T98G cells were demonstrated to have positive nuclear reaction for p53 protein. An ability of T98G cells for spontaneous caspase 3-mediated apoptosis was shown using the antibodies against activated caspase 3. The data obtained suggest that glioblastoma T98G cell line could be used as a convenient model for testing the capacity of natural substances and of pharmaceutical agents that are being developed for the selective induction of caspase 3-mediated apoptosis.

The adult newt retina explanted together with the posterior eye wall and cultivated for a short time in a serum-free medium was tested as an experimental model by several criteria, including the expression of protein markers of the main retinal cell types. Some differences in the expression of specific photoreceptor, interneuron, and glial cell proteins and the localization of acetylcholinesterase activity were found to appear during in vitro cultivation. Using this model, preliminary tests of new cell adhesion glycoproteins from the bovine retina and pigment epithelium were conducted, and the role of pigment epithelial cell proteins in improving cell viability in the cultivated newt retina was revealed. Moreover, the fraction of basic adhesion proteins from the bovine pigment epithelium improved the survival potential of the macroglial (Muller) cell population, compared to that in the control.

Spatial localization and time of expression of glial, neurospecific, and extracellular antigens were studied during retina regeneration in adult newts using antibodies against the glial acidic fibrillar protein (GFAP), neurospecific molecules (N-CAM and PSA-N-CAM), and tenascin (Tn). At the early stages of regeneration (5th day after the operation), slightly differentiated cells in the retina growth area, which are not cellular sources of regeneration, were brightly stained by the antibodies. The one-two-layered retina rudiment formed from the pigment epithelium layer a week later was also intensely stained by the antibodies to GFAP. The retina rudiment cells belong to slightly differentiated precursors of the regenerating retina. It was first shown that the antibodies to GFAP were not only markers of the glial cells, but also markers of slightly differentiated precursors of the regenerating retina. Expression of neurospecific antigens was found in depigmented cells of the retina rudiment. It appeared to have been initiated by cell interactions in the regenerate. An expression of tenascin was found in the cells migrating in the eye cavity and contacting with the retina rudiment cells. The role of tenascin in interaction with the retina rudiment is unknown.

Mechanisms of regulation of cell division in the developing neocortex are largely unknown. The aim of the present study was to investigate the influence of a microenvironment on the fetal neocortex histogenesis. The fetal neocortex from 15-day old Wistar rat embryo was grafted into the neocortex, crushed sciatic nerve and anterior chamber of eye of adult rats. A comparative study of graft development was carried out on 1, 3, 7, 10, 30 days using histological (Nissl stain, hematoxylin-eosin) and immunohistochemical (monoclonal antibody to proliferating cell nuclear antigen, and to glial fibrillary acidic protein) methods. Grafted neuroepithelial cells proliferated in grafts that developed in the neocortex and the anterior chamber of eye for 7 days, and in the sciatic nerve for 10 days. In all grafts differentiating neuroblasts, young neurons and mature neurons were observed 7, 10 and 30 days later, respectively. In 10 days, transplants in the nerve have a glial capsule, in contrast to other sites of grafting. The capsule consists of ependymocytes with microvilli and cilia 30 days later. These cells are GFAP-positive. Our results indicate epigenetic influence on the development of neuroepithelial precursors. The microenvironment of the peripheral nerve is suggested to promote glyogenesis in developing grafts. Afferent inputs do not influence the proliferative potency of brain cell precursors.

The effect of ischemia on the expression of GFAP in astrocytes of cerebrum, hippocampus and cerebellum was studied on rat clinical death model. Cardiac arrest was induced by 10-or 15-min intrathoracic compression of the heart vascular bundle. Immunohistochemical staining showed that GFAP immunoreactivity significantly increased in the white matter, and GFAP-expressing astrocytes appeared in the gray matter. The reaction activity correlated with ischemia duration and phases of postresuscitation process. The obtained data are indicative of possible changes in the astrocytes condition in the absence of manifest lesions of neurons. This brings up the question of the role of glia homeostasis derangements in the formation of brain postresuscitation pathology.

It has been shown that there is a decrease in the content and activity of three neurospecific proteins (neurospecific enolase--NSE, glial fibrillar acid protein--GFAP and creatine kinase CK BB) in various structures of the postmortal brain of schizophrenic patients and those with senile dementia and Alzheimer's disease. The differences in the intensity and localization of these disorders in the above patients' groups have been detected. A previously unknown component of a pathological process in the brain, indicated by the decrease of the CK content and activity has been discovered. It is suggested that the decrease of the content of CK BB results in the development of energy deficit in the brain in patients with mental disorders.

The immune-enzyme analysis was used to determine the quantity of glial fibrillar acid protein in the water-soluble extracts of frontal and limbic cortex, caudate nucleus, medulla oblongata of rats before and after administration of aminazin and haloperidol. The obtained results testify to a decrease of the protein content under the action of both neuroleptics only in the limbic brain cortex of rats.

It was shown that the glial fibrillary acidic protein (GFAP) content in developing (fetal) human brain is sharply increased. The expression of GFAP was observed already on the 7th-8th week after gestation, the GFAP concentration being less than 0.05% in comparison with adult brain. GFAP can be immunohistochemically detected in radial glial cells. At early stages of development the presence of antigenic determinants of 68 kDa and 100 kDa polypeptides interacting with monoclonal antibodies alongside with native GFAP (51 kDa) and its low molecular weight forms was demonstrated. These antigenic determinants cannot be detected at later stages of development and are absent in adult brain. The data obtained testify to changes in the gene expression of intermediate filament proteins at early stages of human brain ontogenesis.

The immunochemical methods were used to study the effect of low-level radiation (0.00645 C/kg and 0.0129 C/kg) on the content and polypeptide composition of glial intermediate filament proteins (GIFP) in different rat brain areas. Changes in glial fibrillar acidic protein (GFAP) concentration were more significant with the dose of 0.0129 C/kg than 0.00645 C/kg. It is suggested that soluble GIFP is more susceptible to the effect of Ca(2+)-dependent proteinases, calpains, than the filament one is, and degrades as early as the first few hours following irradiation. However, low radiation doses were ineffective with respect to calpains activity in the animal brain. The increased Ca2+ concentration enhances considerably GFAP degradation under the effect of calpains I and II. It is suggested that with low radiation doses the rearrangements of glial intermediate filaments may occur due to activation of calpains by releasing Ca ions.

The methods of quantitative immunoelectrophoresis and indirect immunofluorescence were used study the content of glial fibrillary acid protein in 10 serially reinoculated rat gliomas induced primarily by ethylnitrosourea (a total of 135 tumors). It was found that the GFAP content reduced with increase of malignancy. However, wide scattering of the GFAP content in some of the tumors was characteristic of all strains. In the group of slowly growing glial tumors (2 malignant astrocytomas and one malignant oligoastrocytoma) the GFAP content ranged from 50 to 600% and exceeded the normal content two-to threefold on the average. In the group of highly malignant gliomas (4 malignant ependymomas, 2 malignant gliomas, and one glioblastoma) the GFAP content was within the limits of 65-120%. In most cases the GFAP level was below normal or could not be determined at all. At the same time, tumors with a high GFAP content were encountered. The GFAP-positive cells were unevenly distributed in the gliomas: separately, in foci, and around the vessels. Their number increased in the direction of the periphery of the tumor. Intensive fluorescence was noted on the tumor--brain borderline. The content of protein S-100 in the experimental gliomas was always below normal.

Analysis was made of the composition of four structures of human brain in health (n-12), schizophrenia (n-10), and Alzheimer's senile dementia (n-8). Protein maps obtained by means of two-dimensional electrophoresis were used to analyze tissue samples of the structures under study. In the investigation, the neocortex was represented by the frontal cortex (field 10), the old cortex by the hippocamp, the midbrain by black substance, and medulla oblongata by the inferior olive. Comparative study of the protein maps revealed quantitative differences in certain brain structures in health as well as differences between these structures in health and mental pathology.

Basing on the enzymatic and histochemical studies of more than 800 CNS tumours the possibility of application of these methods for the morphologic diagnosis of brain tumour is evaluated. Acid glial fibrillar protein and pituitary hormones were found to be of special value as histochemical markers. Such enzymohistochemical studies may become valuable for solving clinical and diagnostic problems only when they are combined with other morphologic methods of investigation.

The concentration of water-soluble glial fibrillary acidic protein was measured in several regions of human brains (12 schizophrenic patients and 13 patients without any signs of mental disease) using ELISA technique. The content of this protein was lower in thalamus and gyrus cinguli in schizophrenics as compared to normals (p less than 0.01). The protein showed no correlation with sex, age and the terms of autopsy (5 to 7 h after death). The findings suggest that decreasing concentration of the protein might reflect the changes of its synthesis, posttranslational modifications, assembling and disassembling of glial filaments and possibly the effect of psychotropic drugs.