[INTRANUCLEAR ACCUMULATION OF Iba-1 PROTEIN IN MICROGLIOCYTES OF THE HUMAN BRAIN].

Iba-1 protein which is a recognized marker of the microglial cells, was previously detected by the authors in the nucleus of microgliocytes. The present study was aimed to define more exactly these data using the methods of immunohistochemistry and confocal laser microscopy. The study was performed on the fragments of the human brain (n=18, age 25­78 years). The areas examined included cortex, striatum, substantia nigra, and nucleus rubrum. The Iba-1 protein was shown to accumulate in one or several parts of microgliocyte nucleus not identical to the nucleolus or the heterochromatin granules. The reasons for this fact are unclear. It may be speculated that Iba-1 protein besides its major function (involvement in phagocytosis) can perform the role of a transcriptional factor.

[STRUCTURAL AND SPATIAL ORGANIZATION OF MICROGLIA IN THE MOLECULAR LAYER OF RABBIT CEREBELLAR CORTEX].

Using the methods of immunocytochemistry and confocal laser microscopy, structural organization and spatial distribution of microgliocytes in the molecular layer of the cerebellar cortex were studied in 5 adult male rabbits. Reaction to microglial cell marker Iba-1 was highly specific, while until recently their selective detection was impossible in rabbits. In the molecular layer of the cerebellar cortex, two patterns of microgliocyte organization were observed. Most common were the cells with tortuous intricately ramified processes, the main branches of which often had radial direction. Perivascular sparsely-branched spindleshaped microgliocytes were also found. The peculiarities of the structural organization of these cells are related to the protective functions they perform at the level of the blood-brain barrier.

[Simultaneous demonstration of glutamate decarboxylase and synaptophysin in paraffin sections of rat cerebellum].

The article presents highly reproducible and inexpensive protocol for simultaneous demonstration of glutamate decarboxylase (GAD67), the key enzyme of gamma-aminobutyric acid (GABA) synthesis and synaptophysin (SYP), a marker protein of synaptic vesicles using confocal laser microscopy. In the cerebellar cortex, GAD labels Purkinje cells and pinceaux in their basal parts and is unevenly distributed in the neuropil of molecular and granular layers. SYP clearly marks the contours of large dendrites of Purkinje cells in molecular layer, while in the granular layers it labels parts of cerebellar glomeruli--the terminals of the mossy fibers. GAD-immunopositive structures (GABA-ergic axons of stellate cells--Golgi cells) are often located at periphery of the glomeruli. In the peripheral zone of the glomeruli, colocalization of GAD- and SYP-immunopositive structures was observed, suggesting the presence of GABA-ergic synapses in this zone.

[Nestin expression in ependymal cells of lateral ventricles of the rat brain in aging].

It is known that during development of the brain, with the progress of ependendymocyte differentiation from radial gliocytes, the synthesis of nestin is stopped. However, it was shown that in the ependyma of the lateral brain ventricles nestin synthesis was resumed in response to ischemic injury. The aim of the present study was to test the hypothesis of possible re-expression of nestin in the ependyma in aging. The study was performed on male Wistar rats aged 4 (n = 4) and 28 months (n = 3). In older animals the expression of nestin was demonstrated in the ependyma of the lateral ventricles of the brain. It was also found that the area of the medial and upper walls of the lateral ventricle contained the regions of ependyma, in which all cells had intense cytoplasmic staining. The causes of the phenomenon described remain unclear.