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alpha 1-Acid glycoprotein (orosomucoid) was purified from the human and murine blood sera using phenol deproteinization. As opposed to the murine protein, the human orosomucoid bound the fluorescent dye ethidium bromide but lost this ability after treatment with beta-mercaptoethanol, which breaks disulfide bonds. Disulfide bonds between the Cys23 and Cys165 residues of the human orosomucoid and between the Cys91 and Cys184 residues of the murine orosomucoid were identified.

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Human alpha 1-acid glycoprotein (orosomucoid, AGP) was purified to homogeneity by a two-step procedure using phenol and chloroform deproteinization of serum with subsequent preparative electrophoresis on agarose gel. It was obtained 0.15-0.3 mg of protein from 1 ml of serum. Human alpha 1-AGP binds ethidium bromide but not DNA. Neither other human serum proteins nor mice and rat alpha 1-AGP bind ethidium bromide. This property of human orosomucoid depends on its amino acid sequence rather than on the carbohydrate part of the molecule.

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Comparative analysis of serum DNA content in healthy rats, rats with experimental alloxan diabetes, and the rats with the diabetes compensated by transplantation of the embryonal pancreas into the anterior chamber of the eye. In the course of diabetes the concentration of free-circulating serum DNA reliably increase 10-12 times, and the compensation of the diabetes returns it to the norm. The revealed relationship may be used for diagnostics of initiation and full compensation of the insulin-dependent diabetes.

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Analysis of the blood serum of healthy and infected with malaria plasmodium mice showed a steep rise in content of linear double-stranded DNA (0.2-0.5 and 2-15 gamma/ml, respectively). Some physico-chemical properties of serum DNA and a DNA-associated glycoprotein (M approximately 40 kDa) are determined.

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Computer analysis of the maps of distribution of intensively labelled neurons (ILN) in the frontal sections of area 6 of the frontal neocortex and area CA 1 of the dorsal hippocamp was performed in 1-day-old mice who received a single injection of 3H-thymidine on the 13th-17th day of embryogenesis (E 13-E 17). It has been revealed that ILN are distributed in rather close, vertically oriented groups. In mice exposed to isotope in E 14-E 16, the average number of ILN in a group was 4.44 +/- 0.25 for area 6 and 4.35 +/- 0.16 for area CA 1. The data available have confirmed an earlier postulated hypothesis on the discrete arrangement of neurogenesis loci in the ventricular zone of the embryonic brain. Additional calculations have allowed to conclude that in E 14-E 16 period the locus of the ventricular neocortex during one mitotic cycle produces 7-9 cells starting the neuronal differentiation, while during the whole period of neurogenesis in the neocortex the column consisting of 84-108 neurons is formed, which is close to the number of neurons in a minicolumn of the neocortex (110 cells).

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Pregnant CBA mice were given a single injection of 3H-thymidine (3H-T) (10 microCi/g) on days 11-19 of pregnancy. The mouse progeny was sacrificed on the first day of postnatal life. Brain was embedded into paraffin and durcupan. Radioautographs of paraffin and semithin sections were prepared and employed for mapping the site of intensely labeled neurons (ILN) in the CAI area of the hippocampus (H). ILN appeared in the CAI area after 3H-T injection, namely on embryonic day 12 (E 12). The ILN number reached a maximum after isotope injection on 2 14-15 and then dramatically fell down. The neurogenesis in the suprapyramidal layer of the CAI area slightly outstripped the neurogenesis in the pyramidal and infrapyramidal layers. At early times of the experiment the CAI area exhibited the predominance of single ILN, whereas at late times paired ILN prevailed. That fact might be linked with the replacement during the neurogenesis of asymmetric critical mitoses of the germinative neuronal precursors by symmetric critical mitoses. Analysis of the ILN distribution in the CAL area revealed mosaic clusters of ILN alternating with unlabeled or mildly labeled neurons. Those groups were most remarkable in mice injected with 3H-T on E 14 and E 15. The mosaicism of the neurogenesis in the H is regarded as the result of heterochronous neuronal production by local parts of the germinative zone, each of which builds up a separate radial segment of the H.

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The mitotic and pyknotic indices were counted in the local germinative zones of Ammon's horn and dentate gyrus of normal mice from embryonic day 18 (ED 18) to postnatal day 60 (PD 60). The local germinative zone of Ammon's horn (the suprafimbrial zone) forms from ED 16 but the first pyknoses appear in it from ED 20. After a rapid increase of the mitotic and pyknotic indices with a maximum reached on PD 3 there is a sharp decrease of their values corresponding to the reduction of the suprafimbrial zone. The local germinative zone of the dentate gyrus is generated from ED 14, however pyknoses appear from PD 1. The greatest values of the mitotic and pyknotic indices fall within PD 3. Later on the values of both indices gradually decrease, however, they are sufficiently pronounced even on PD 60. It is suggested that the mitotic death by means of pyknotic degeneration is connected with elimination of the spontaneous mutations of glial precursors in the germinative zones of the brain.

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Mapping on arrangement of mitoses (M) and pyknoses (P) has been performed in the mouse developing hippocamp. Analysis on the M arrangement confirms the data known on the hippocampal germinative zones and time of their reduction in the mouse ontogenesis. Previously unknown germinative zone of Ammon's horn has been revealed--the suprafimbrial zone that exists since the 16th day of embryogenesis up to the 7th postnatal day. Analysis on the P arrangement demonstrates that they appear in the hippocampal germinative zones during the perinatal periods. Localization of the P corresponding to that of the M agree with the data on "mitotic" death of the germinative and glial cells in the developing brain.

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The mitotic index, index of cell labelling with 3H-thymidine, picnotic index and parameters of mitotic cycle were determined in the subependyme and subgranular germinative brain zones, as well as the index of labelling of glioblasts in the neocortex of the intact 20 days old mice and mice subjected to malnutrition from the 10th till the 20th day of life. The subependyme and subgranular zones did not differ by the generation time and periods of mitotic cycle but the subgranular zone had a lower proliferative pool. Upon malnutrition the parameters under study in both the germinative zones suffered no marked changes but the number of dying cells with picnotic nuclei forming at the stage of mitosis increased greatly; the number of proliferating glioblasts in the neocortex decreased markedly. A conclusion is drawn that the model of malnutrition used in the present work influences the cell production in the germinative zones in young mice mainly by means of intensification of mitotic cell death.

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By means of computer analysis, size distribution of neurons and glial cells together with the label of 3H-thymidin labelled cells were studied in cytoarchitectonic layers of the field 1 in the mouse parietal cortex injected with the isotope on the 5th day of life and killed 1 month later. In some animals, 3 days before 3H-thymidin injection, the parietal region in the right hemisphere was perforated. The labelled cells were subdivided into 2 groups according to their size: astrocytes (A) and small gliocytes (mg). Labelled A and mg were stated to be rather evenly distributed along the cytoarchitectonic layers in the field 1. The trauma performed resulted in increasing amount of the labelled A and MG in the operated hemisphere. Uniformity in distribution of the labelled A and mg, occupying the position of satellites, did not change considerably at the trauma, in spite of general quantitative increase of the labelled glial cells. One month after the trauma, body dimentions of the mice labelled with A and mg did not considerably differ from those of intact animals, while the size of nerve cells increased. Thus, neurons in the parietal cortex of a growing brain respond to brain trauma with hypertrophy of cell bodies, and glial populations--with increase of their number.

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The proliferation and directions of cell differentiation in tectum opticum were studied in the young frogs under the conditions of normal development and upon brain trauma by means of 3H-thymidine autoradiography. The same types of cells were shown to be able of proliferation in both the cases: cells of the ventricle zone and glioblasts (gliocytes) in all other tectum layers. A study of directions of the tectum proliferating cells' differentiation in the frogs has shown that the proliferating cells differentiate mainly in the ependyme tanicytes in the ventricle layer 1 and gliocytes in the other tectum layers. The trauma did not change the direction of proliferating cells' differentiation towards the formation of neurons. The complete regeneration is observed in the tectum layer 1 only.

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Postnatal histogenesis of the parietal area of the neocortex and proliferative capacity in it of the main cell types were studied in mice under normal conditions and in stab wound of the brain by analysing 3H-thymidine-labeled cells on semithin sections. As revealed, microneurons failed to form in the parietal cortex of mice during the postnatal period either by migration of undifferentiated cells or by proliferation. Injury of the right hemisphere did not cause any change in the way of histogenetic transformations of cells migrating into the cortex of the parietal area in the direction of their differentiation into microneurons.

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After the injury of the thalamus right hemisphere in tadpoles and young frogs X. laevis, 3H-thymidine incorporated in the cells of the thalamus ventricular zone, but not in the middle and large neurons of the type of neurons of the trigeminal nerve mesencephalic nucleus and the large ganglion cells of VI and VIII layers of the thalamus cortex. The brain trauma in tadpoles resulted in the activation of cell proliferation in the ventricular zone, whereas in young frogs the proliferation of glyocytes was activated. The relation of the proliferative reaction of certain types of brain cells to the trauma to the loss of ability for brain regeneration is discussed.

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On the basis of both the authors' and published data, the structure and morphogenetic functions are analyzed for two zones of mammal brain during postnatal period: fascia dentata of hippocampus and cerebellar cortex. A conclusion is drawn that the local cambial zones arise in those brain regions which acquire in the process of morphogenesis a high degree of spatial separation from the ventricular zone. The main function of the cambial zones in question is the formation of a large number of microneurons during postnatal period.

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Potencies of brain cells to DNA synthesis and proliferation were studied in two weeks old and adult mice in the norm and after the brain mechanical injury. No labeled large and middle neurons were found in the brain of intact and operated animals both under the pulse 3H-thymidine incorporation and saturation of mice with 3H-thymidine during 36 hrs. The same types of brains cells were labeled both in intact and operated two weeks old and adult mice: glial cells, cells of the subependymal zone, cells of the dentate gyrus inner margin, and sometimes, cells having characteristics of microneurons. The number of glial cells in the temporal cortex of intact mice diminished with the age. Under the brain trauma, the proliferative reaction of glia was expressed in a similiar way both in two weeks old and adult mice. The index of labeled cells in the subependymal zone is the same in these two age groups. With the age the cellular mass of subependymal zone decreases, rather than proliferative tendencies of supependymal zone. The brain traumatization resulted in the increase of labeled subependymal cell only under the direct injury of subependymal zone.

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The behaviour of labelled (3H-thymidine) glial cells was studied in the brain of intact mice and mice with mechanical trauma of brain. Formation of pairs of labelled cells and their subsequent disjunction in the brain regions under study occurs at different rates. The rates of these processes in white matter and subependymal zone exceed those in parietal cortex, thalamus and hypothalamus. The brain traumatization does not influence the rate of disjunction of separated glial cells. Angles between axes of separated cells are different in the brain regions under study. In cortex and white matter, separated cells with axial angles equal to 180 degrees predominate whereas in thalamus, hypothalamus and subependymal zone many separated cells have axial angles below 180 degrees (120-160 degrees). The possible relationship between the form of the brain regions under study and the value of axial angles of separated cells is discussed.

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The local cellular proliferation takes place in the inner part of the dentate gyrus granular layer, the subgranular zone, of mice. The proliferating cells of the subgranular zone are one of two sources of postnatal neurogenesis of the granular layer (another source-cells of the subependymal zone). The subgranular zone becomes markedly thinner with the age but even in adult mice the cellular proliferation occurs in it. Under the brain trauma, the proliferation of the subgranular zone cells is activated. Besides cell division in the subgranular zone, there is insignificant proliferation in the differentiated part of the granular layer. Special studies are, however, necessary to identify dividing cells in the differentiated part of the granular layer.

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