GABA and glutamate: exosytosis and Na + – dependent release from the rat brain nerve terminals under extremal conditions

1Borisova, TA, 1Pozdnyakova, NG, 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. 2005, 11 ;(1-2):098-102
Publication Language: Russian
It is demonstrated for the first time that hypcrgravity stress affects nerve signal transmission, in particular, the release of GABA (the most common inhibitory neurotransmitter) and L-[14 С] glulamate (predominant excitatory neurotransmitter). A comparative analysis of release of GABA and glutamate from the rat brain synaptosomes (nerve terminals) shows that exposure of animals to hypcrgravity loading (10G for 1 hour) evokes oppositely directed alterations in inhibitory and excitatory signal transmission. Significant changes occurred in release of neurotransmitters induced by stimulating exocytosis with the agents, which depolarized nerve terminal plasma membrane. Depolarization-evoked Ca2+~-stimulated release was more abundant for GABA (7.2±0.54 % and 11.74 ± 12 % of total accumulated labclfor control and hypergravity, respectively, (P ≤ 0.05)) and was essentially less for glutamate (14.4±0.7 % and 6,2±1.9%, (P ≤ 0.05)) after exposure of animals to centrifuge induced artificial gravity.
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