Interaction of the cholinergic and catecholaminergic systems of the brain during a change in the motivational behavior of animals.

It is generally recognized that food-motivated reactions of animals occur with the participation of cortical and subcortical structures of the brain (hypothalamus, limbic-reticular complex), between which complex neurochemical interactions are established. It is believed that activation of various structures of the central nervous system at various levels of food-motivated excitation is associated with the peculiarities of the mediation of nerve impulses in the corresponding brain structures. Moreover, the concept of close structurofunctional interrelationships among various mediator systems of the brain, in particular, the cholinergic and catecholaminergic systems, are finding increasing confirmation. However, the corresponding positions are based primarily on electrophysiological and biochemical investigations, which give integrative indices for relatively large regions of brain tissue (in comparison with micro- and ultrastructures). The structurochemical interactions of the cholinergic and catecholaminergic systems of the brain in the regulation of food-motivated behavior of animals at the cellular and subcellular levels have practically not been studied. In connection with the aforementioned, we were interested in studying the activity of acetylcholinesterase (AChE) and monoamine oxidase (MAO), which participate in the metabolism of acetylcholine and catecholamines, respectively, in the process of a change in the food-motivated behavior of animals in the micro- and ultrastructures of certain hypothalamic nuclei and the cerebral cortex. In the present investigation we used methods of quantitative histochemistry and electron cytochemistry.

[Effect of anticholinesterases on acetylcholinesterase distribution in the human and animal brain (cytochemical study)]. / Osobennosti raspredeleniia atsetilkholinésterazy v mozge cheloveka i zhivotnykh pri deistvii na organizm atsetilkholinésteraznykh veshchestv (tsitokhimicheskoe issledovanie).

With the use of quantitative histochemistry and cytochemistry methods the localization of acetylcholinesterase in the brain of man and animals in cases of acute poisoning with organophosphorus compounds was studied. In the brain of animals poisoned with chlorophos the activity of the enzyme, according to cytophotometric findings, dropped 2 or 3 times, this drop being more pronounced in the neuropile. In the human brain, the drop of the acetylcholinesterase activity caused by organophosphorus compounds was the most pronounced in the neuropile and the neurons of the cortex, caudate nucleus and hypothalamus. The cytochemical examinations of the enzyme in the cases of poisoning showed absence of the sediment on the basal membrane of the capillaries and the membranes of the nervous fibres and synapses. However, acetylcholinesterase was found to remain active in some neurons at the nuclear membrane and in the endoplasmic reticulum (presence of the sediment in the form of individual granules or discrete zones). Probability of the acetylcholinesterase activity inhibition mainly in the outer (in relation to the neuron) barrier systems and possibility of reparative processes in the neurons are discussed.

The influence of antibrain antibodies on the level of enzyme activity and ultrastructure of brain.

The paper is concerned with the effect antibrain antiserum may exert on the activity of succinic dehydrogenase, glutamic dehydrogenase, cytochrome oxidase, and peroxidase. By means of quantitative cytochemistry and electron microscopy it was demonstrated that activity of succinic dehydrogenase activity or cytochrome oxidase increased in the cortex and hypothalamus following the injection of anti-cortex or anti-hypothalamic serum. There were no changes of glutamic dehydrogenase and peroxidase found. Nonspecific alterations of neuronal fine structures were observed in both the cortex and the hypothalamus of rabbits treated with antiserum.

[Acetylcholinesterase and monoamine oxidase activity in hypothalamic structures during water deprivation]. / Aktivnost' atsetilkholinesterazy i monoaminoksidazy v strukturakh gipotalamusa pri vodnoi deprivatsii.

Light, electron microscopy and cytospectrophatometry were used to study the level of acetylcholinesterase and monoamine oxidase in the hypothalamus nuclei during different periods of water deprivation in white rats. It was demonstrated that depending upon the time of deprivation, there is a successive triggering of the cholino- adrenoreactive systems in the hypothalamus. However, the main role in the perception of water deprivation in the triggering of the regulatory mechanisms is played by the cholinergic mediator system in the lateral preoptic area, lateral and supraoptical nuclei of the hypothalamus.

[Distribution of ribonucleoprotein particles in brain tissue cells (electron-cytochemical study)]. / Raspredelenie ribonukleoproteidnykh chastits v kletkakh mozga (élektronno-tsitokhimicheskoe issledovanie).

Distribution of ribonucleoprotein (RNP) particles in the cell nuclei, incorporated into brain tissue was studied. RNP were stained according to the modified Bernhard method. The nuclei of all studied cells contained all RNP particles known for other eukaryocytes. Along with RNP described in literature, the nuclei, cytoplasm and neuron processes demonstrated new RNP-containing particles to be the size of 100-150 nm. In line with the amount of condensed chromatin and the content of RNP particles in the cell nuclei, they were classified according to the activity of the protein-synthesizing apparatus.

[Ultrastructural features of cerebral synapses in schizophrenic patients]. / Ul'trastrukturnye osobennosti sinapsov mozga bol'nykh shizofreniei.

The paper is concerned with ultrastructural traits of synapses in the frontal lobe, supraoptical nucleus of the hypothalamus and caudal nucleus of the brain in 12 schizophrenic patients and 8 normals (the period of autopsy was 4 hours following death). The results demonstrated 2 types of changes: 1) slightly expressed changes (a decrease of the extent of active zone contacts, changed forms in the synaptical vesicles); 2) extremely expressed or degenerative changes in the synapses (an appearance of fibrillar structures, glycogene granules, degeneration of synaptical endings of a dark type).

[Electron-cytochemical distribution of acetylcholinesterase, monamine oxidase and Mg2+-ATPase in the human hypothalamus]. / Elektronno-tsitokhimicheskoe raspredelenie atsetilkholinésterazy, monoaminooksidazy i Mg2+-ATF-azy v gipotalamuse cheloveka.

The distribution of acetylcholinesterase, monoaminoxidase and ATP-ase was studied in human hypothalamus by means of electron microscopy. The study demonstrated a possibility of differentiation of the hypothalamic neurons according to phases of neurosecretion. These data were achieved on the basis of electron cytochemistry in detecting ATP-asa in the nuclei of neurons. Comparing literary data concerning the nonmediator role of acetyl-choline and catecholeamines with personal studies, the authors demonstrate the internal and external barrier functions of acetylcholinesterase and monoamineoxidase in the brain.

[A quantitative assessment of enzyme activity by cytophotometry using a standard]. / Kolichestvennaia otsenka aktivnosti fermentov metodom tsitofotometrii s primeneniem étalona

The usage of the standard has been offered in cytospectrophotometrical measurements of enzymatic activities that are revealed histochemically. A tetrazolium method was used to demonstrate lactate dehydrogenase activity in sections of the rat brain. As a standard, a mixture of the enzyme (a crystalline forme of LDG) and gelatine was taken. The method of standardization permits fulfilling a quantitative comparison of heterogenic biological materials.