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
Publication Language: Russian
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
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