Effect of tetanus toxin on noradrenalin liberation from rat brain synaptosomes

A purified preparation of tetanus toxin (TT) (80–800 MLD/mg protein) was shown to induce liberation of both endogenous and exogenous (labeled with¹⁴C) noradrenalin (NA) from isolated nerve endings (synaptosomes) of the rat brain. Within the range of concentrations studied TT does not inhibit secretion of NA evoked by depolarization of synaptosomes by different methods in vitro.Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 2, pp. 148–150, February, 1980.     

Effect of tetanus toxin on contractility of the actomyosin-like protein of rat brain

Preparation of purified actomyosin-like protein (ALP) was isolated from the coarse fraction of rat brain mitochondria. The ALP preparation contained Mg(Ca)-ATPase activity, inhibited by 0.1% deoxycholate, together with acetylcholinesterase activity and contractility (superprecipitation reaction). The contraction of ALP and ATPase activity were considerably reduced by tetanus toxin. Inactivated toxin had no effect. The possible functional role of ALP in the maintenance and secretion of mediators by nerve endings is discussed.Laboratory of General Pathology of the Nervous System, Institute of Normal and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 78, No. 12, pp. 24–27, December, 1974.     

Neuropathological effects of injection of tetanus toxin into certain structures of the rat brain

The neuropathological effects of local injection of tetanus toxin (TT) into various structures of the brain were studied in experiments on rats. Definite neuropathological changes were observed in the animals, different from those found after injection of TT elsewhere. As a rule the action of TT in a given region of the brain was local. The experiments confirm the theory of generator mechanisms of neuropathological syndromes, according to which specific manifestations of the corresponding syndrome are determined by the location of a generator of pathologically enhanced excitation in a certain brain structure.Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 2, pp. 124–126, February, 1979.     

Neurospecific S-100 protein in synaptosomes of the rat cerebral cortex

A nonspecific S-100 protein was found in the composition of low-molecular-weight acid proteins from synaptosomes of the rat cerebral cortex by capillary microdisc electrophoresis in 15% polyacrylamide gel with 0.1% sodium dodecysulfate and with the aid of a highly purified marker protein. The S-100 protein accounted for 15–20% of the lowmolecular-weight acid synaptosomal proteins.Research Institute of Experimental Medicine, Academy of Medical Sciences of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR V. S. Il'in). Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 2, pp. 164–166, February, 1976.     

Generators of pathologically enhanced excitation as determinant structures in the spinal cord

With the aid of tetanus toxin, which disturbs various types of inhibition, generators of excitation were created in the left and right anterior horns of the lumbar spinal cord in rats. The regimes of activity of the generators differed: the left-sided generator, formed during the longer action of the toxin, in response to activation by trigger stimulation first produced tonic, and then intermittent activity, or individual spontaneous discharges, whereas the righ-sided generator produced only tonic activity. If one generator was blocked by glycine, the other continued to operate as before. Activation of one generator led to concomitant depression of the effects of the other. During separate activation of each generator, all the spinal and supraspinal motoneuron pools synchronously reproduced the character of activity of the generator functioning at that particular moment. The generator thus played the role of a determinant structure, determining the behavior of the system. The results are examined from the standpoint of the general concept of the role of determinant structures in the activity of the nervous system and the theory of generator mechanisms of neuropathological syndromes characterized by hyperactivity of systems.Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 5, pp. 515–519, May, 1977.     

Effect of visual deprivation on composition of structural proteins of the rabbit central visual system

The composition of membrane proteins of the visual cortex and superior colliculus of normal and visually deprived (for 2.5 months after birth) rabbits was studied by disk electrophoresis in polyacrylamide gel. Membrane proteins were extracted consecutively with 1% solution of Triton X-100 and 0.1% solution of sodium dodecylsulfate. One fraction, consisting of high-molecular-weight proteins, was not found in the membrane proteins of the central visual system of the light-deprived rabbits, and the relative percentage of proteins in the various fractions also differed from normal. It can be concluded from these results that visual deprivation gives rise to considerable quantitative and qualitative changes in the composition of the brain membrane proteins, with some specificity toward the central visual structures.Laboratory of Biohistochemistry, Brain Institute, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR B. N. Klosovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 10, pp. 1209–1211, October, 1976.     

Effect of K+-depolarization on the physical state of membrane lipids in rat brain synaptosomes

Laboratory of Biochemistry, Research Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR G. N. Kryzhanovskii.) Translated from Byulleten Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 1, pp. 24–27, January, 1989.     

Changes in incorporation of labeled amino acids into individual protein fractions of rat brain tissue after intrauterine hypoxia

Laboratory of Experimental Brain Pathology, Research Institute of Pediatrics, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR M. Ya. Studenikin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 10, pp. 351–352, October, 1990.     

Electrophoretic transfer of viral proteins to nitrocellulose sheets and detection with peroxidase-bound lectins and protein A

Peroxidase-bound protein A and lectins in combination with precipitable substrates were used to detect viral proteins and glycoproteins on ‘Western blots’. The sensitivity of various methods was compared, including radioiodinated protein A, enzyme immunosorbent assay and peroxidase staining with DAP. The sensitivity of the peroxidase reaction, its rapidity and low cost compared with other methods make this a useful choice for developing protein bands transferred to nitrocellulose paper. In addition, a procedure was devised to clarify and fix nitrocellulose sheets for direct quantification of the precipitated substrate by densitometric analysis.     

Subcellular distribution of the immunoreactive peptide histidine isoleucine in the rat brain and release from synaptosomes in vitro

Subcellular fractionation studies of rat brain homogenate revealed that peptide histidine isoleucine-like immunoreactivity (PHI-LI) was enriched in synaptosomal preparations. PHI-LI was released by high potassium concentrations from synaptosomal pellets incubated in vitro. These results suggest a possible physiological role of PHI in the central nervous system as a neurotransmitter or modulator of synaptic function.     

Effect of acute hypoxia in the antenatal period on uptake of labeled amino acids into rat brain proteins and tissue homogenates

Incorporation of leucine-¹⁴C and methionine-³⁵S into tissue homogenates and protein isolated from various parts of the brain of rats exposed to acute hypoxia in the antenatal period was investigated. Besides active incorporation of amino acids into proteins in other parts of the brain, inhibition of protein synthesis also was observed in certain structures in the experimental animals, especially in the hippocampus. Changes in the uptake of labeled amino acids by the tissue homogenates did not correspond to the level of their incorporation into protein in the individual brain structures. The experimental results points to a disturbance of the intensity of protein metabolism and of the function of the blood-brain barrier in late ontogeny in rats exposed to intrauterine hypoxia.Radiology Group, Moscow Research Institute of Psychiatry, Ministry of Health of the RSFSR. (Presented by Academician of the Academy of Medical Sciences of the USSR E. V. Shmidt.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82., No. 9, pp. 1061–1064, September, 1976.     

Action of tetanus toxin and colchicine on synaptic membranes of the rat cerebral cortex

Purified tetanus toxin (TT), in experiments in vitro, was shown to affect neither the Na,K-ATPase activity of the synaptic membrane fraction of the rat cerebral cortex nor the inhibition of Na,K-ATPase activity produced by electrical stimulation of a suspension of synaptic membranes, nor the binding of GABA-³H by synaptosomes. TT and colchicine (1 mM) reduced the osmotic sensitivity of the nerve endings. Colchicine, in low concentrations (10^–5 to 10^–3 M), does not affect Mg- and Na,K-ATPase but, in higher concentrations (10^–2 M), it inhibits the activity of both ATPases considerably.Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathological Physiology, Academy of Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 139–142, February, 1977.     

Effects of pyrrolidone-2 and gamma-butyrolactone on rate of incorporation of14C-leucine into proteins of various brain structures and cerebral arterial tissues

Department of Pharmacology, Erevan Medical Institute. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 106, No. 11, pp. 571–572, November, 1988.     

Effect of naphthene acids on learning and protein synthesis in the mouse brain

S. M. Kirov Azerbaijan University, Baku. (Presented by Academician of the Academy of Medical Sciences of the USSR I. P. Ashmarin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 109, No. 1, pp. 47–49, January, 1990.