2.9. The initial rate and accumulation of [3H] GABA by the nerve terminals

Synaptosomes were diluted by the standard salt solution containing aminooxyacetic acid (100 μM). The protein concentration in the synaptosome samples was 200 μg/ml. The synaptosome preparations were pre-incubated at 37 °C for 10 min, the remdesivir aliquots in DMSO were added to the synaptosome suspensions, and the samples were further incubated for 10 min. Control synaptosome samples contained DMSO in related concentrations. The uptake was initiated by the addition of GABA and [³H] GABA (1 μM or 50 nM, 4.7 μCi/ml, respectively). To determine the initial rate of [³H] GABA uptake, this process was completed in 1 min by filtering aliquots through Whatman GF/C filters. After washing twice with 5 ml of ice-cold standard salt solution, the filters were dried, and then were suspended in the organic counting scintillant and counted using a scintillation counter. Nonspecific binding of [³H] GABA was evaluated in cooled samples filtered immediately after the adding of radioactivity [49]. [³H] GABA uptake data were collected in triplicate from several (n) independent experiments performed with different synaptosome preparations.