Artificial gravity and functional plasticity of nerve system. L-[14C]-glutamate uptake by nerve terminals from rat cerebellum and cerebral hemispheres under hypergravity stress.

We have investigated the effects of altered gravity on the kinetic parameters of glutamate transport activity. We observed no differences in Km values for cerebellum and cerebral hemisphere nerve terminals (synaptosomes) between control rats- 18,2 +/- 7,6 micromoles (cerebellum), 10,7 +/- 2,5 micromoles (cerebral hemispheres) and animals exposed to hypergravity- 23,3 +/- 6,9 micromoles (cerebellum), 6,7 +/- 1,5 micromoles (cerebral hemispheres). The similarity of this parameter for the two studied groups of animals showed that affinity of glutamate transporter to substrate in cerebellum and cerebral hemispheres was not sensitive to hypergravity stress.