Ouabain modulates the toxic action of glutamate in dissociated cultures of rat cerebellar granule cells

It is shown that treatment of cultured crebellar granule cells with ouabain (10 μM, 90 min) before their exposure to the toxic action of glutamate (100 μM, 15 min) results in a significant reduction of neuronal mortality caused by this neurotransmitter, whereas treatment with ouabain after exposure to glutamate increases the toxicity of ouabain. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 8, pp. 163–166, August, 1996     

Activation of nitric oxide pathway mediated by metabotropic glutamate receptors in primary cultures of cerebellar granule cells

Stimulation of L-glutamate receptors (GluRs) is thought to produce neuron death through the elevation of free intracellular Ca²⁺ levels, leading to activation of Ca²⁺/calmodulin-dependent synthesis of cytotoxic amounts of NO·. In the present study, NO synthase activation mediated by mGluR stimulation is investigated in primary cultures of granule cells (CGrC). It is found that a selective agonist of mGluRs, DL-1-aminocyclopentane-trans-1,3-dicarboxylic acid (ACPD), raises both the cGMP and nitrite (NO₂ ⁻) levels, which are used as a biochemical index to study the enzymatic NO· release from L-arginine. This effect is abolished by applying both Nω-nitro-L-arginine methyl ester (NAME) and DL-2-amino-4-phosphonobytyric acid (AP4), and is independent of Ca²⁺. In contrast, the α-amino-3-hydroxy-5-methylisoxarole-4-propionnate (AMPA)-induced increase in cGMP content is eliminated by the preincubation of CGrC with 4 mM EGTA-chelated Ca²⁺. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 7, pp. 46–49, July, 1995 Presented by Yu. A. Romanov, Member of the Russian Academy of Medical Sciences     

Calcium reduces mitochondrial membrane potential of cultured rat cerebellum granule cells under toxic action of glutamate

Glutamate-induced decrease in mitochondrial membrane potential of granule cell is prevented by cobalt ions and the noncompetitive selective antagonist of NMDA-receptors MK-801. Similar to glutamate, the calcium ionophore A23187 reduces this potential. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 4, pp. 378–380, April, 1997     

Modulation of voltage-dependent calcium channels by glutamate in rat cerebellar granule cells in culture

Voltage-dependent calcium channels of cerebellar granule cells maintained in a Ca²⁺-free depolarising solution were recorded using the cell-attached configuration of the patch-clamp technique. An increase in the maximum open probability of calcium channels and a shift in their activation curve toward more hyperpolarising potentials were found in the presence of glutamate, a natural, excitatory amino acid. Such an increase in the activity of calcium channels was not due to ionic fluxes activated by glutamate, and was probably produced by a second messenger pathway triggered by the binding of glutamate to its receptor.     

Neuroprotection of microglia conditioned media from apoptotic death induced by staurosporine and glutamate in cultures of rat cerebellar granule cells

Microglia, the immune cells of the mammalian CNS, have often been indicated as dangerous effector cells for their activation in response to traumatic CNS injuries or immunological stimuli and for their involvement in many chronic neurodegenerative diseases. Recently, several in vitro and in vivo studies have emphasized that microglial activity is essential in promoting neuronal survival. We have tested the efficacy of media directly conditioned by microglia or conditioned by microglia after having been exposed to apoptotic neurons, towards neuroprotection of rat cerebellar granule cells (CGCs) challenged with staurosporine or glutamate. Apoptotic death of CGC caused by staurosporine, as well as by a mild excitotoxic stimulus delivered through sub-chronic glutamate treatment, was significantly counteracted by microglia conditioned media. On the other hand, an acute excitotoxic insult delivered through a short pulse of glutamate exposure in the absence of magnesium and resulting in a mix of apoptotic and necrotic death was only marginally counteracted by microglia conditioned media. The present results extend the available information regarding the neuroprotective role of microglia and support the usefulness of employing the culture approach for perspective identification of neuroprotective factors released by these cells. Furthermore, the use of media previously exposed to apoptotic neurons to elicit the neuroprotective response of microglia, indicate the feasibility to re-create also in the isolated culture conditions, at least some of the elements at the basis of neuron/microglia cross-talk.     

Effect of intraperitoneal spermin on oxidative processes in isolated mitochondria of rat liver in hypothermia

Effect of intraperitoneal administration of spermin on oxidative phosphorylation and calcium capacity of isolated liver mitochondria was studied in normo- and hypothermic rats. Hypothermia stimulates mitochondrial respiration without decreasing the contingency and increases calcium capacity. Spermin suppresses mitochondrial respiration, the effect being stronger in hypothermia. In high doses spermin prevents stimulating effect of hypothermia on respiration and reduces the increase in calcium capacity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 5, pp. 526–528, May, 1998     

Effects of apolipoproteins C on oxidative phosphorylation in rat liver mitochondria

It is shown that apoC-III, but not other apoC proteins, components of very low density lipoproteins (apoC-I, apoC-II, apoC-III), reduced the rate of mitochondrial respiration in various metabolic states. This effect depended on the dose of apoprotein, type of oxidized substrate, and the presence of Ca ions in the incubation medium. ApoC-III completely blocked oxidative phosphorylation during oxidation of palmitoyl carnitine by mitochondria, while the respiration rate in metabolic state 4 remained unchanged. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 184–186, August, 2000     

Effect of doxorubicin on oxidative phosphorylation in brain mitochondria

Inin vitro experiments, antineoplastic anthracycline antibiotic doxorubicine caused deenergization of rat brain mitochondria due to oxidation-phosphorylation uncoupling and inhibition of succinate oxidase system. Reduced production and oxidation of succinic acid is the most early effect of doxorubicin on mitochondrial oxidation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 10, pp. 445–447, October, 1999     

Investigation of the mechanism of action of ouabain and cyclic AMP of the transport of calcium ions by rat heart mitochondria

The action of ouabain and cyclic AMP on the Ca-accumulating capacity and outflow of Ca²⁺ ions from loaded rat heart mitochondria was studied by the tetracycline probe method. In the course of the investigations no effect of ouabain on these processes was found. Cyclic AMP did not act on Ca binding by the mitochondrial membrane but it induced rapid liberation of Ca²⁺ from organelles loaded with these ions.Department of Molecular Pharmacology, Medico-Biological Faculty, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR S. S. debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 158–160, February, 1977.     

Mechanisms of reciprocal control of reactions and processes involved in energy production by mitochondria

Correlations between respiration rates in the mitochondria in different states are studied using various oxidation substrates. Specific features and integration between different functional cycles are substrate-dependent. It is suggested that variations of the mitochondrial function correspond to specific phases of pathological process. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 9, pp. 282–284, September, 1996     

Phospholipid composition of liver mitochondria in experimental hemorrhagic shock

Heparin used as an anticoagulant in modeled hemorrhagic shock decreases the phosphatidylcholine and increases the phosphatidylethanolamine contents in the mitochondria. Accumulation of lysophosphatidylcholine in whole mitochondria and their inner membrane is observed in hemorrhagic shock. At the same time, hemorrhagic shock decreases phosphatidylcholine content in the inner and outer mitochondrial membranes and increases phosphatidylethanolamine content in the outer membranes. Modification of phospholipid composition of mitochondrial membranes is a mechanism responsible for impaired energy production in liver mitochondria in hemorrhagic shock. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 7, pp. 43–45, July, 1997     

Neuroprotective properties of nootropic dipeptide GVS-111 inin vitro oxygen-glucose deprivation, glutamate toxicity and oxidative stress

Argon anoxia and glucose deprivation were used for modeling of ischemic damage in the cultures of cerebellar granule cells. Protective effect of peptide piracetam analogue GVS-111 was demonstrated. GVS-111 prevented neurodegeneration induced by glutamate and oxidative stress. In contrast to GVS-111, piracetam did not attenuate neurocytotoxic effect of glutamate. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 10, pp. 418–421, October, 2000     

Two-factor correlation analysis of the distribution of morphofunctional properties of mitochondria during irradiation

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol.115, N ^o 2, pp.215–218, February, 1993     

Altered activity of respiratory chain enzymes in mitochondria of peripheral blood lymphocytes after irradiation in rats

The effect of ionizing radiation on the activity of succinate dehydrogenase (complex II) and succinate-cytochrome C-oxidoreductase in peripheral blood lymphocytes is studied on rats exposed to whole-body γ-irradiation in doses of 9.5–10.5 Gy. On day 5 after irradiation, when the number of lymphocytes is sharply reduced, enzyme activity in the remaining population is found to be reliably increased. These changes are not related to biological cycles. It is assumed that most of the survivors after high-dose irradiation are the cell populations maintaining a high level of oxidative phosphorylation in mitochondria. Translated fromByulleten' Eksperimental'noi Giologii i Meditsiny, Vol. 120, N ^o . 8, pp. 158–159, August, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Preparation of dissociated Zebrafish spinal neuron cultures

The method described here explains a simple protocol for how to prepare dissociated Zebrafish spinal neuron cultures. The neurons grow fast in a simple culture medium and at room temperature. Considering the advantages afforded by the optical transparency of the Zebrafish embryo combined with the powerful molecular perturbation techniques available, this technique has potential to further advance molecular analysis of axon growth and guidance.     

Changes in the state of mitochondria and intercellular junctions of hepatocytes for the internal application of siliceous water

Structural-adaptive alterations in mitochondria and intercellular junctions are found in the liver against the background of elevated silicon when mineral siliceous water and silicon solution are applied internally. It is established that an increase of the number of tight and gap junctions takes place during the period of declining bioenergetic processes in hepatocytes. As the number and area of mitochondria increase, the extent of the intercellular junctions shrinks. These changes may be considered to be important components in the mechanism of action of siliceous water. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 348–351, March, 1996 Presented by V. V. Kupriyanov, Member of the Russian Academy of Medical Sciences     

Action of antioxidants and chelating agents on thyroxine-induced swelling of mitochondria

The rate of swelling of rat liver mitochondria in the presence of thyroxine depended only a little on the cationic composition of the medium (KCl, NaCl, or choline chloride), which suggests an unselective increase in mitochondrial membrane permeability for cations in the presence of thyroxine. The antioxidant -tocopherol and -ionol, in concentrations completely suppressing peroxidation of lipids, did not affect thyroxine-induced swelling of the mitochondria, which is thus not connected with lipid peroxidation. The kinetics of swelling and its inhibition by the Ca-chelating agent EGTA are evidence that Ca²⁺ is essential for induction of this process. Thyroxine swelling of mitochondria is evidently based on activation of membrane phospholipase in these organelles.N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Orekhovich.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 10, pp. 426–428, October, 1977     

The generation of granule cells during the development and evolution of the cerebellum

The cerebellum coordinates vestibular input into the hindbrain to control balance and movement, and its anatomical complexity is increasingly viewed as a high-throughput processing center for sensory and cognitive functions. Cerebellum development however is relatively simple, and arises from a specialized structure in the anterior hindbrain called the rhombic lip, which along with the ventricular zone of the rostral-most dorsal hindbrain region, give rise to the distinct cell types that constitute the cerebellum. Granule cells, being the most numerous cell types, arise from the rhombic lip and form a dense and distinct layer of the cerebellar cortex. In this short review, we describe the various strategies used by amniotes and anamniotes to generate and diversify granule cell types during cerebellar development.     

Changes in phospholipid composition of mitochondria in the medulla oblongata and frontal lobes of the cerebral hemispheres in hemorrhagic shock in cats

Considerable regional differences in the phospholipid composition of mitochondrial membranes are found in the brain of cats in the terminal phase of hemorrhagic shock. The most prominent alteration is noted in the medulla oblongata and consists in a progressive elimination of phosphatidylcholine. Changes in the main phospholipids in mitochondrial membranes of the cerebral hemispheres are less pronounced and consist in a drop of phosphatidylinositol and phosphatidylethanolamine. Accumulation of lysophosphatidylcholine and lysophosphatidylethanolamine is a regular feature of the studied mitochondria. Accumulation of lysophosphatidylserine is found primarily in mitochondrial membranes of the medulla oblongata. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 4, pp. 387–391, April, 1996