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In rabbits the acute form of experimental allergic encephalomyelitis was caused by inoculation of emulsion of homologous myelin from spinal cord with Freund's adjuvant. In terminal paralytic period of the disease the animals were subcutaneously administered with 2-14C-acetate and a dose 50 micronCi per 100 g of body weight 2 hrs before death. From lumbar and stem sections of the central nervous system purified fractions of cerebrosides and gangliosides were isolated and their specific radioactivity was determined. The intensity of the cerebrosides synthesis was found to be distinctly decreased not only in the more impaired lumbar region but also in the stem section of the central nervous system, where the centers of demyelinization were not observed. The intensity of the gangliosides synthesis was also markedly decreased, in spite of that their content was not altered in the central nervous system under experimental allergic encephalomyelitis.

Chronic intoxication of guinea pigs was induced by intracutaneous inoculation of tricresylphosphate (TCP). The brain stem and spinal cord total phospholipids and total, free and esterified cholesterol were determined during the severe neuroparalytic stage of TCP intoxication. The content of phosphilipids and of total cholesterol was not altered, but cholesterol esters appeared to accumulate both in the brain stem and the spinal cord. Cholesterol esters are characteristic products of degraded myelin sheaths.

Capacity of basic protein (SCP) to prevent the development of experimental allergic encephalomyelitis was studied in guinea pigs. This protein is shown to possess no antiencephalitogenic effect. Distribution of this protein in various areas of the central and peripheral nervous system was investigated using immune serum to the protein. The protein under study is shown to localize mainly in the peripheral nervous system: spinal roots, sciatic nerve, brachial plexus nerves, vagus and optic nerves, and in the central nervous system areas rich in nerve fibres: spinal cord, medulla oblongata, pons varolii, corpus callosum, white substance of cerebral cortex. The protein content in corpus callosum and white substance of cerebral cortex is extremely insignificant. Using the Ouchterlony reaction of double immunodiffusion the protein under study was found in the myelin membrane of the peripheral nervous system and its immunological identity to the myelin basic protein (P-2) is shown.

Intracellular K activity (aik) in frog motoneurons of isolated spinal cord as measured by double-barrelled K+-selective microelectrodes revealed mean values as follows: 74.8 +/- 2.5 mM at the beginning of the recording and 51.6 +/- 2.9 mM afterwards (mean +/- SE). The average value of the resting potential of motoneurons (Em) was 54.1 +/- 1.2 mV. The difference between Ek (potassium equilibrium potential) and Em was 25.0 +/- 0.98 mV. Stimulation of ventral roots of spina-cord decreased aik both in normal and in Ca2+-free Ringer solution. No changes of aik occurred in synaptic stimulation without spike potentials.

Content of gangliosides was decreased in white substance of brain hemispheres and in spinal cord of dogs with typical symptoms of allergic encephalomyelitis. The decrease in content of less polar fractions was compensated by an increase in concentration of more polar gangliosides. After an intracisternal administration of the antibrain antibodies the content of gangliosides was also decreased in brain cortex and white substance of hemispheres. The data obtained suggest that the neurone membranes are impaired under the pathological conditions as well as that the antibrain antibodies are important for development of the structural impairments observed.

The distribution of tubulin, actin and neurofilamentous protein (molecular weight 160 kD) in the spinal cord neurons of mice embryos cultivated in monolayer was studied by means of monoclonal FITC- and rhodamine labeled antibodies. It was found that nerve cell development induced migration of tubulin from the neuronal soma to its processes. The tubulin filling in different processes was uneven at certain stages of cell differentiation. The actin content in the neuron was negligible. Its point concentration was observed along the neuronal processes in the vicinity of focal contacts with the lining cells. Main content of neurofilamentous protein is concentrated in the neuronal body and proximal parts of neurites. The results obtained present the pattern of distribution of cytoskeletal proteins in the spinal cord neurons.

Basic protein (SCP) known as antiencephalytogenic was isolated from the bull spinal cord and spinal roots. The protein is purified to a molecular homogeneous state, some of its physicochemical properties are studied. Molecular homogeneity of the protein is established by the method of disk electrophoresis in 15% polyacrylamide gel with sodium dodecyl sulphate present and by analytic ultracentrifugation. During electrophoresis in 15% polyacrylamide gel at pH 4.0 the protein movement occurs only in one zone, and at pH 7.0 three closely located zones are formed. The protein molecular weight determined by different methods is about 13500. The protein amino acid composition is determined and it is shown that 9.6 mole of amide nitrogen falls on 1 mole of the protein. The presence of the tertiary structure in the protein is supposed.

Some characteristics of the myelin basic protein from dog spinal cord were studied. The basic protein has a molecular weight of 18,000; the isoelectric point is 9.5. The amino acid composition of the protein was determined. Electrophoresis in 15% polyacrylamide gel revealed the heterogeneity of the basic protein. The EAE-activity of the basic protein was tested on guinea pigs.

The distribution of proteolipids (PL) was studied in various parts of the nervous system of certain mammals and subcellular structures of rat brain. Soluble PL of various degrees of purification from lipids have been obtained from gray and white matter of cerebral hemispheres of cattle as well as from mitochondrial, synaptosomal and two myelin fractions of rat brain. Certain properties, protein and lipid composition and molecular weight of the PL isolated have been studied. Together with some general properties certain differences have been observed in the protein and especially in the phospholipid composition of PL isolated from the grey and white matters and subcellular particles. The PL of white matter and myelin are similar to each other in their protein and phospholipid composition but are different from those of grey matter and mitochondria, the latter in turn being also similar in their protein and phospholipid composition. The data obtained make the existence of at least two types of PL probable: one in myelin and another in mitochondria. The first is characterised by the presence of a protein corresponding to DM-20 of molecular weight of 29000, besides the main PL protein of 35-36000 molecular weight, as well as by the predominance of phosphatidylserine which forms 61% of phospholipids bound to PL. The second is characterized by the existence of one main protein corresponding to PL but of a somewhat higher molecular weight (39--40000). The phospholipid composition of the PL is rich in cardiolipin which form 38--46% of bound phospholipids.

The content of protein and RNA in motoneurons of anterior horns of the spinal cord of rats flown for 18.5 days aboard the biosatellite Cosmos--936 was measured. Ten rats were exposed to weightlessness and 9 rats to artificial gravity. The RNA content in both rat groups remained at the preflight level 4.5--9.5 hours after recovery. The protein content in the motoneuronal cytoplasm of weightless and centrifuged rats was by 42 and 30% lower than in vivarium control. The protein content in the motoneuronal nuclei of the above rats was by 31 and 24% lower than in the controls. Twenty-five days postflight the RNA content in weightless rats was by 22% higher than and in centrifuged rats similar to that in the controls. The protein content in the cytoplasm returned to normal in both rat groups, whereas that in the nuclei of weightless rats was by 37% higher than in the controls.

Main encephalitogenic protein was isolated from bovine medulla spinalis and separated into homogenous polypeptide fractions by gel filtration; some of these fractions had the high encephalitogenic activity. The main protein and its fractions, possessing the encephalitogenic activity, caused a development of cross-reacting antibodies and a sensitization to intracutaneous administration of encephalitogenic preparations in animals. Non-encephalitogenic main protein sensitized animals only to this protein and did not induce the formation of distinct amount of antibodies. The amino acid composition of the encephalitogenic polypeptide is exhibited.

The paper deals with the analysis and assessment of basic results concerning investigations of nervous tissue proteins and their metabolism. The studies have been made in research institutions of the Ukrainian SSR for 60 years (1922-1982) and are of importance for comprehending the role of these proteins in the structural and biochemical organization of the nervous tissue and participation in its physiological functions and pathological processes. Special attention is payed to elucidation of the results and prospects for studies dealing with physicochemical properties and biological role of certain neurospecific proteins--protein S-100, antigen D (protein 14-3-2), the basic encephalitogenic protein myelin and protein P2.

Less pronounced intensity of extrapyramidal hyperkineses and aggravation of motor disturbances in patients with diffuse sclerosis occurring under the effect of tegretol prompted the authors to study the action of this drug on the course of experimental allergic encephalomyelitis. Daily administration of tegretol in a dose of 375 mg/kg retarded the development of the affection and produced a marked adynamia in the animals. Slowing down of the dominant rhythm and depression of its amplitude were recorded on the EEG. Shifts in the potassium and sodium content and reduced brain cholesterase activity were noted. The authors ascribe these changes to a mediated action of tegretol upon deep-seated cerebral structures.

Na and K content has been studied in tissues of the hazel grouse Bonasa bonasia, black grouse Lyrurus tetrix, capercaillie Tetrao urogallus, domestic hen Gallus domesticus and turkey hen Meleagris gallopavo. With respect to the increase in potassium and sodium content, the tissues investigated in wild species form the following sequence: major thoracal muscle (red), minor thoracal muscle (white), gastrocnemius muscle, left ventricle of the heart, stomach muscles, brain hemispheres, spinal cord. Domestic birds exhibit lower sodium level in stomach muscles. Potassium distribution in tissues of wild birds is more even than in domestic ones; in the latter potassium content of the heart is significantly lower than that of other muscles. The main bulk of muscles in wild birds contain more potassium and less sodium as compared to the muscle tissue of domestic ones. No interspecific differences were found in potassium and sodium content of white and red pectoral muscles.

By means of doublewave cytophotometry of the histological sections and smears performed with the device mtsfv-1 (lomo) it has been demonstrated that differentiation of some neurons of the spinal ganglia and the spinal cord is accompanied with hyperreplication of DNA amount exceeding the diploid contents, while the large neurons in layer III of the tectum opticum remain diploid. In the process of differentiation an increased amount of RNA and histones, and decreasing portion of histones sented for the microcalculator b3-21.

By means of two-wavelength spectrophotometry, according to Tsanev and Markov, a stability of RNA content has been demonstrated in rabbit spinal cord sections treated with cold perchloric acid: it was only after 18 and particularly 48 hr incubation of the section in a 16% perchloric acid solution that the total tissue RNA began to be extracted. Cytospectrophotometrical study of the motoneurons of spinal cord anterior horns and perineuronal glial cells in gallocyanin -- chrome alum stained sections has shown a rapid loss of RNA under effect of the cold perchloric acid: as early as after a 2 hr treatment, about 2/3 of the whole cellular RNA was extracted from the motoneurons, while about 1/2 from their glial satellite cells. Hydrolysis of the rest of RNA was found out in the neurons and in the neuroglia only after a 18 hr extraction with the perchloric acid. Similarities and differences in the features of neuronal and glial RNA are discussed.

Resynthesis of aspartate via glutamate was decreased 6-8-fold in rat brain spinal cord tissues due to distinct inhibition of aspartate aminotransferase in acute alcohol intoxication. Consumption of glutamic acid was distinctly increased 1.5-2-fold in tissues of the central nervous system but its metabolism was altered. Normalization occurred within 12-24 hrs after the intake of alcohol. In the state of chronic alcohol intoxication the enzymatic activity was marked increased in brain and spinal cord; in this case the response to a single alcohol administration was altered as compared with acute alcohol intoxication.

Transient and steady-state L-glutamate-activated membrane currents were investigated by means of intracellular perfusion, voltage clamp techniques and concentration clamp in spinal cord neurons of 6-11 day chick embryos. The Hill coefficient was found to equal 1 for transient and 2 for steady-state components. Concentration of L-glutamate evoking half effect decreased during development more than 10 times for the steady-state component whereas it remained constant for the transient component. Existence of two types of glutamate-activated receptors in the membrane of spinal cord neurons at early stages of embryonic development is supposed.

When pregnant rats are administered chlororganic pesticide dilor, certain ultrastructural changes are observed in neurocytes and in myelin fibers, in the spinal cord, that demonstrates some disorders in cellular and tissue metabolism. In the newborn spinal cords a retarded differentiation is observed against the background of an intense cellular metabolism. By means of the electron paramagnetic resonance technique, an increasing concentration of free radicals in the brains and spinal cords of the pregnant animals and in their one-month-old offsprings is demonstrated. The investigation on fatty acid composition of lipids in pregnant test animals demonstrates a decrease in cholysterine, steroids and some fatty acids in myelin fractions and in synaptosomic membranes.

Intracisternal administration of extractant-1M 90 degrees C acetic acid within 15 min into intact rats neutralizes the left and the right half of the lumbar part of the rat spine thus prolonging passive extension, while dorsal application causes the muscle tension of the back extremity. The effects are probably due to the peptidergic asymmetry of the rat spine.

A study was made of the content of phospholipids, cerebrosides and cerebroside sulfates in the central nervous system of mice with experimental acute viral encephalomyelitis. No considerable changes in phospholipid content were revealed. A significant drop in the content of cerebrosides and cerebroside sulfates was defected in the CNS, being more pronounced in the spinal cord of sick animals. The reduction in the content of glycolipids can be explained by myelin disintegration and by the effect of viruses on the olygodendrocytes in which cerebrosides and cerebroside sulfates are synthesized.

A comparison of the plasmalogen contents of phospholipid classes of 12 organs and tissues of pig (brain, heart, lung, liver, spinal cord, kidney, spleen, pancreas adrenula, muscles, blood plasma, aorta) was carried out, using reaction microthin-layer chromatography. Only phosphatidylethanolamine, phosphatidylcholine and phosphatidylserine were found to contain plasmalogen form. The minor components were represented by phosphatidic acid and phosphatidylglycerol. Phosphatidylethanolamine was shown to contain the plasmalogen form making up from 9% (in liver) to 80% (in spinal cord).