Artificial gravity and glutamatergic transmission in cerebral hemispheres

1Borisova, TA, 1Krisanova, NV, 2Himmelreich, NH
1Palladin Institute of Biochemistry of National Academy of Sciences of Ukraine, Kyiv, Ukraine
2O.V. Palladin Institute of Biochemistry of the NAS of Ukraine, Kyiv, Ukraine
Kosm. nauka tehnol. 2002, 8 ;(5-6):062-065
https://doi.org/10.15407/knit2002.05.062
Publication Language: Russian
Abstract: 
We investigated the effect of hypergravity stress (created by centrifugation of rats at lOg over the course of 1 hour) on the L- [14 С] glutamate release from isolated rat brain cerebral hemispheres nerve terminals. It is shown that the hypergravity stress exerted a different influence on the Ca2+-dependent and the Ca2++-independent components of L- [14 С] glutamate release. The Ca2+-dependent L- [14 С] glutamate release stimulated with a standard stimulus, 35 mM KC1, was decreased by more than one half as a result of the hypergravity stress and was equal to 14.4±0.7 % for control animals and 6.2±1.9 % for animals exposed to hypergravity (P ≤  0.05). At the same time we observed no statistically significant difference in the Ca 2+-independent component of L- [14 С] glutamate release. Our data allows us to make a suggestion that the redistribution of the neurotransmitter between cytosolic and vesicular pools in nerve terminals occurs in altered gravity conditions.
Keywords: brain, glutamate, hypergravity stress
References: 
1. Gazenko O. G., Genin A. M., Il'in E. A., et al. Adaptation to weightlessness and its physiological mechanisms. Izv. AN SSSR, 1, 5—18 (1980) [in Russian].
2. Chernigovsky V. N. Problems of Space Biology, 15, 355 p. (Nauka, Moscow, 1971) [in Russian].
3. Cotman C. W. Isolation of synaptosomal and synaptic plasma membrane fractions. Methods Enzymol., 31, 445—452 (1974).
https://doi.org/10.1016/0076-6879(74)31050-6
4. D'Amelio F., Fox R. A., Wu L. C., et al. Quantitative changes of GABA—immunoreactive cells in the hindlimb representation of the rat somatosensory cortex after 14-day hindlimb unloading by tail suspension. J. Neurosci. Res., 44 (6), 532—539 (1996).
https://doi.org/10.1002/(SICI)1097-4547(19960615)44:6<532::AID-JNR3>3.0.CO;2-C
5. D'Amelio F., Wu L. C., Fox R. A., Daunton N. G., et al. Hypergravity exposure decreases gamma-aminobutyric acid immunoreactivity in axon terminals contacting pyramidal cells in the rat somatosensory cortex: a quantitative immunocytochemical image analysis. J. Neurosci. Res., 15 (53), 135—142 (1998).
https://doi.org/10.1002/(SICI)1097-4547(19980715)53:2<135::AID-JNR2>3.0.CO;2-8
6. Fox R. A. Effects of Artificial Gravity: Central Nervous System Neurochemical Studies. NASA Taskbook, 619— 620 (1997).
7. Gegelashvili G., Schousboe A. Cellular distribution and kinetic properties of affinity glutamate transporters. Brain Res. Bull., 45 (3), 233—238 (1998).
https://doi.org/10.1016/S0361-9230(97)00417-6
8. Hughes-Fulford M. Altered cell function in microgravity. Exp. Gerontol., 26 (2-3), 247—256 (1991).
https://doi.org/10.1016/0531-5565(91)90017-G
9. Krasnov I. B. Gravitational neuromorphology. Adv. Space Biol. Med., 4, 85—110 (1994).
https://doi.org/10.1016/S1569-2574(08)60136-7
10. Larson E., Howlett B., Jagendorf A. Artificial reductant enhancement of the Lowry method for protein determination. Analitical Biochemistry, 155, 243—248 (1986).
https://doi.org/10.1016/0003-2697(86)90432-X
11. Lipton S. A., Rosenberg P. A. Exitatory amino acids as a final common pathway for neurologic disorders. New Engl. J. Med., 330, 613—662 (1994).
https://doi.org/10.1056/NEJM199403033300907
12. Paschenko P. S., Sukhoterin A. F. The structural organization of the normal rat area postrema and under conditions of cronic exposure to gravitational loads. Morfologiia, 117, 36—41 (2000).
13. Rao V. L., Murthy C. R. K. Uptake, release and metabolism of glutamate and aspartate by rat cerebellar subcellular preparations. Biochem. Mol. Biol. Int., 29, 711—717 (1993).
14. Savina E. A., Alekseev E. I. Functional state of the posterior lobe of rats exposed aboard the biosatellite «Cosmos-936». Arkh. Anat. Gistol. Embriol., 78 (1), 62—68 (1980).
15. Siesjo B. K. Basic mechanisms of traumatic brain damage. Ann. Emergency Med., 22, 959—969 (1993).
https://doi.org/10.1016/S0196-0644(05)82736-2

16. Vatassery G. T., Lai J. C. K., Smith W. E., Quach H. T. Aging is associated with a decrease in synaptosomal glutamate uptake and an increase in the susceptibility of synaptosomal vitamine E to oxidative stress. Neurochem. Res., 23, 121 — 125 (1998).
https://doi.org/10.1023/A:1022495804817